diff --git a/src/server/BreCal/__init__.py b/src/server/BreCal/__init__.py
index eb832f5..263203e 100644
--- a/src/server/BreCal/__init__.py
+++ b/src/server/BreCal/__init__.py
@@ -34,7 +34,7 @@ from BreCal.stubs.df_times import get_df_times
 
 from BreCal.services.schedule_routines import setup_schedule, run_schedule_permanently_in_background
 
-def create_app(test_config=None):
+def create_app(test_config=None, instance_path=None):
 
     app = Flask(__name__, instance_relative_config=True)
     app.config.from_mapping(
@@ -45,7 +45,11 @@ def create_app(test_config=None):
     else:
         app.config.from_mapping(test_config)
 
+    if instance_path is not None:
+        app.instance_path = instance_path
+
     try:
+        import os
         print(f'Instance path = {app.instance_path}')
         os.makedirs(app.instance_path)
     except OSError:
diff --git a/src/server/BreCal/api/shipcalls.py b/src/server/BreCal/api/shipcalls.py
index 396dc93..68a927e 100644
--- a/src/server/BreCal/api/shipcalls.py
+++ b/src/server/BreCal/api/shipcalls.py
@@ -1,12 +1,17 @@
 from flask import Blueprint, request
 from webargs.flaskparser import parser
-from marshmallow import Schema, fields
+from marshmallow import Schema, fields, ValidationError
 from ..schemas import model
 from .. import impl
-from ..services.auth_guard import auth_guard
+from ..services.auth_guard import auth_guard, check_jwt
+from BreCal.validators.input_validation import validate_posted_shipcall_data, check_if_user_is_bsmd_type
+from BreCal.validators.input_validation_shipcall import InputValidationShipcall
+from BreCal.database.sql_handler import execute_sql_query_standalone
 
 import logging
 import json
+import traceback
+import werkzeug
 
 bp = Blueprint('shipcalls', __name__)
 
@@ -14,7 +19,16 @@ bp = Blueprint('shipcalls', __name__)
 @auth_guard() # no restriction by role
 def GetShipcalls():
     if 'Authorization' in request.headers:
-        token = request.headers.get('Authorization')
+        token = request.headers.get('Authorization')    # see impl/login to see the token encoding, which is a JWT token. 
+
+        """
+        from BreCal.services.jwt_handler import decode_jwt
+        jwt = token.split('Bearer ')[1] # string key
+        payload = decode_jwt(jwt) # dictionary, which includes 'id' (user id) and 'participant_id'
+
+        # oneline:
+        payload = decode_jwt(request.headers.get("Authorization").split("Bearer ")[-1])
+        """
         options = {}
         options["participant_id"] = request.args.get("participant_id")
         options["past_days"] = request.args.get("past_days", default=1, type=int)
@@ -31,8 +45,21 @@ def PostShipcalls():
     try:
         content = request.get_json(force=True)
         loadedModel = model.ShipcallSchema().load(data=content, many=False, partial=True)
+
+        # read the user data from the JWT token (set when login is performed)
+        user_data = check_jwt()
+
+        # validate the posted shipcall data & the user's authority
+        InputValidationShipcall.evaluate_post_data(user_data, loadedModel, content)
+        
+    except ValidationError as ex:
+        logging.error(ex)
+        print(ex)
+        return json.dumps({"message":f"bad format. \nError Messages: {ex.messages}. \nValid Data: {ex.valid_data}"}), 400
+        
     except Exception as ex:
         logging.error(ex)
+        logging.error(traceback.format_exc())
         print(ex)
         return json.dumps("bad format"), 400
 
@@ -45,8 +72,24 @@ def PutShipcalls():
 
     try:
         content = request.get_json(force=True)
-        logging.info(content)
         loadedModel = model.ShipcallSchema().load(data=content, many=False, partial=True)
+
+        # read the user data from the JWT token (set when login is performed)
+        user_data = check_jwt()
+
+        # validate the PUT shipcall data and the user's authority
+        InputValidationShipcall.evaluate_put_data(user_data, loadedModel, content)
+        
+    except ValidationError as ex:
+        logging.error(ex)
+        print(ex)
+        return json.dumps({"message":f"bad format. \nError Messages: {ex.messages}. \nValid Data: {ex.valid_data}"}), 400
+
+    except werkzeug.exceptions.Forbidden as ex:
+        logging.error(ex)
+        print(ex)
+        return json.dumps({"message":ex.description}), 403
+        
     except Exception as ex:
         logging.error(ex)
         print(ex)
diff --git a/src/server/BreCal/api/ships.py b/src/server/BreCal/api/ships.py
index e31147e..96bceb2 100644
--- a/src/server/BreCal/api/ships.py
+++ b/src/server/BreCal/api/ships.py
@@ -1,11 +1,14 @@
 from flask import Blueprint, request
 from .. import impl
-from ..services.auth_guard import auth_guard
-from marshmallow import EXCLUDE
+from ..services.auth_guard import auth_guard, check_jwt
+from marshmallow import EXCLUDE, ValidationError
 from ..schemas import model
 import json
 import logging
 
+from BreCal.validators.input_validation import check_if_user_is_bsmd_type
+from BreCal.validators.input_validation_ship import InputValidationShip
+
 bp = Blueprint('ships', __name__)
 
 @bp.route('/ships', methods=['get'])
@@ -24,8 +27,21 @@ def GetShips():
 def PostShip():
 
     try:
+        # read the user data from the JWT token (set when login is performed)
+        user_data = check_jwt()
+
+        # check, whether the user belongs to a participant, which is of type ParticipantType.BSMD
+        # as ParticipantType is an IntFlag, a user belonging to multiple groups is properly evaluated.
+        is_bsmd = check_if_user_is_bsmd_type(user_data)
+        if not is_bsmd:
+            raise ValidationError(f"current user does not belong to BSMD. Cannot post shipcalls. Found user data: {user_data}")
+        
         content = request.get_json(force=True)
         loadedModel = model.ShipSchema().load(data=content, many=False, partial=True)
+
+        # validate the request data & user permissions
+        InputValidationShip.evaluate_post_data(user_data, loadedModel, content)
+
     except Exception as ex:
         logging.error(ex)
         print(ex)
@@ -39,8 +55,15 @@ def PostShip():
 def PutShip():
 
     try:
+        # read the user data from the JWT token (set when login is performed)
+        user_data = check_jwt()
+
         content = request.get_json(force=True)
-        loadedModel = model.ShipSchema().load(data=content, many=False, partial=True, unknown=EXCLUDE)
+        loadedModel = model.Ship().load(data=content, many=False, partial=True, unknown=EXCLUDE)
+
+        # validate the request data & user permissions
+        InputValidationShip.evaluate_put_data(user_data, loadedModel, content)
+        
     except Exception as ex:
         logging.error(ex)
         print(ex)
@@ -53,13 +76,20 @@ def PutShip():
 @auth_guard() # no restriction by role
 def DeleteShip():
 
-    # TODO check if I am allowed to delete this thing by deriving the participant from the bearer token    
     try:
+        # read the user data from the JWT token (set when login is performed)
+        user_data = check_jwt()
+        ship_id = request.args.get("id")
+        
         if 'id' in request.args:
             options = {}
             options["id"] = request.args.get("id")
         else:
             return json.dumps("no id provided"), 400
+
+        # validate the request data & user permissions
+        InputValidationShip.evaluate_delete_data(user_data, ship_id)
+        
     except Exception as ex:
         logging.error(ex)
         print(ex)
diff --git a/src/server/BreCal/api/times.py b/src/server/BreCal/api/times.py
index 2c90397..e1b3786 100644
--- a/src/server/BreCal/api/times.py
+++ b/src/server/BreCal/api/times.py
@@ -1,9 +1,11 @@
 from flask import Blueprint, request
 from ..schemas import model
 from .. import impl
-from ..services.auth_guard import auth_guard
+from ..services.auth_guard import auth_guard, check_jwt
 import json
 import logging
+from marshmallow import ValidationError
+from BreCal.validators.input_validation_times import InputValidationTimes
 
 bp = Blueprint('times', __name__)
 
@@ -30,6 +32,17 @@ def PostTimes():
         # body = parser.parse(schema, request, location='json')
         loadedModel = model.TimesSchema().load(data=content, many=False, partial=True)
 
+        # read the user data from the JWT token (set when login is performed)
+        user_data = check_jwt()
+
+        # validate the request
+        InputValidationTimes.evaluate_post_data(user_data, loadedModel, content)
+        
+    except ValidationError as ex:
+        logging.error(ex)
+        print(ex)
+        return json.dumps(f"bad format. \nError Messages: {ex.messages}. \nValid Data: {ex.valid_data}"), 400
+
     except Exception as ex:
         logging.error(ex)
         print(ex)
@@ -46,6 +59,17 @@ def PutTimes():
         content = request.get_json(force=True)
         loadedModel = model.TimesSchema().load(data=content, many=False, partial=True)
 
+        # read the user data from the JWT token (set when login is performed)
+        user_data = check_jwt()
+        
+        # validate the request
+        InputValidationTimes.evaluate_put_data(user_data, loadedModel, content)
+
+    except ValidationError as ex:
+        logging.error(ex)
+        print(ex)
+        return json.dumps(f"bad format. \nError Messages: {ex.messages}. \nValid Data: {ex.valid_data}"), 400
+
     except Exception as ex:
         logging.error(ex)
         print(ex)
@@ -58,11 +82,16 @@ def PutTimes():
 @auth_guard() # no restriction by role
 def DeleteTimes():
 
-    # TODO check if I am allowd to delete this thing by deriving the participant from the bearer token
-
     if 'id' in request.args:
         options = {}
         options["id"] = request.args.get("id")
+
+        # read the user data from the JWT token (set when login is performed)
+        user_data = check_jwt()
+
+        # validate the request
+        InputValidationTimes.evaluate_delete_data(user_data, times_id = request.args.get("id"))
+
         return impl.times.DeleteTimes(options)
     else:
         logging.warning("Times delete missing id argument")
diff --git a/src/server/BreCal/api/user.py b/src/server/BreCal/api/user.py
index bbd5b4b..2c3c1a0 100644
--- a/src/server/BreCal/api/user.py
+++ b/src/server/BreCal/api/user.py
@@ -4,6 +4,7 @@ from .. import impl
 from ..services.auth_guard import auth_guard
 import json
 import logging
+from marshmallow import ValidationError
 
 bp = Blueprint('user', __name__)
 
@@ -14,6 +15,11 @@ def PutUser():
     try:
         content = request.get_json(force=True)
         loadedModel = model.UserSchema().load(data=content, many=False, partial=True)
+        
+    except ValidationError as ex:
+        logging.error(ex)
+        print(ex)
+        return json.dumps(f"bad format. \nError Messages: {ex.messages}. \nValid Data: {ex.valid_data}"), 400
 
     except Exception as ex:
         logging.error(ex)
diff --git a/src/server/BreCal/database/enums.py b/src/server/BreCal/database/enums.py
index 3092fd8..a3c7de1 100644
--- a/src/server/BreCal/database/enums.py
+++ b/src/server/BreCal/database/enums.py
@@ -1,8 +1,8 @@
-from enum import Enum, IntFlag
+from enum import IntEnum, Enum, IntFlag
 
 class ParticipantType(IntFlag):
     """determines the type of a participant"""
-    NONE = 0
+    undefined = 0
     BSMD = 1
     TERMINAL = 2
     PILOT = 4
@@ -11,12 +11,17 @@ class ParticipantType(IntFlag):
     PORT_ADMINISTRATION = 32
     TUG = 64
 
-class ShipcallType(Enum):
+class ShipcallType(IntEnum):
     """determines the type of a shipcall, as this changes the applicable validation rules"""
+    undefined = 0
     INCOMING = 1
     OUTGOING = 2
     SHIFTING = 3
 
+    @classmethod
+    def _missing_(cls, value):
+        return cls.undefined
+
 class ParticipantwiseTimeDelta():
     """stores the time delta for every participant, which triggers the validation rules in the rule set '0001'"""
     AGENCY = 1200.0 # 20 h * 60 min/h = 1200 min
@@ -26,7 +31,9 @@ class ParticipantwiseTimeDelta():
     TUG = 960.0 # 16 h * 60 min/h = 960 min
     TERMINAL = 960.0 # 16 h * 60 min/h = 960 min
 
-class StatusFlags(Enum):
+    NOTIFICATION = 10.0 # after n minutes, an evaluation may rise a notification
+
+class StatusFlags(IntEnum):
     """
     these enumerators ensure that each traffic light validation rule state corresponds to a value, which will be used in the ValidationRules object to identify
     the necessity of notifications.
@@ -36,3 +43,26 @@ class StatusFlags(Enum):
     YELLOW = 2
     RED = 3
 
+class PierSide(IntEnum):
+    """These enumerators determine the pier side of a shipcall."""
+    PORTSIDE = 0 # Port/Backbord
+    STARBOARD_SIDE = 1 # Starboard / Steuerbord
+        
+class NotificationType(IntFlag):
+    """determines the method by which a notification is distributed to users. Flagging allows selecting multiple notification types."""
+    UNDEFINED = 0
+    EMAIL = 1
+    POPUP = 2
+    MESSENGER = 4
+
+class ParticipantFlag(IntFlag):
+    """
+    | 1 | If this flag is set on a shipcall record with participant type Agency (8), 
+    all participants of type BSMD (1) may edit the record.
+    """
+    undefined = 0
+    BSMD = 1
+
+    @classmethod
+    def _missing_(cls, value):
+        return cls.undefined
diff --git a/src/server/BreCal/database/sql_handler.py b/src/server/BreCal/database/sql_handler.py
index 59497e3..2d85175 100644
--- a/src/server/BreCal/database/sql_handler.py
+++ b/src/server/BreCal/database/sql_handler.py
@@ -1,9 +1,11 @@
 import numpy as np
 import pandas as pd
+import pydapper
 import datetime
 import typing
-from BreCal.schemas.model import Shipcall, Ship, Participant, Berth, User, Times
+from BreCal.schemas.model import Shipcall, Ship, Participant, Berth, User, Times, ShipcallParticipantMap
 from BreCal.database.enums import ParticipantType
+from BreCal.local_db import getPoolConnection
 
 def pandas_series_to_data_model():
     return 
@@ -19,8 +21,81 @@ def set_participant_type(x, participant_df)->int:
     participant_type = participant_df.loc[participant_id, "type"]
     return participant_type
     
+def get_synchronous_shipcall_times_standalone(query_time:pd.Timestamp, all_df_times:pd.DataFrame, delta_threshold=900)->int:
+    """
+    This function counts all entries in {all_df_times}, which have the same timestamp as {query_time}.
+    It does so by:
+    1.) selecting all eta_berth & etd_berth entries 
+    2.) measuring the timedelta towards {query_time}
+    3.) converting the timedelta to total absolute seconds (positive or negative time differences do not matter)
+    4.) applying a {delta_threshold} to identify, whether two times are too closely together
+    5.) counting the times, where the timedelta is below the threshold
 
+    returns: counts
+    """
+    assert isinstance(query_time,pd.Timestamp)
 
+    # get a timedelta for each valid (not Null) time entry
+    time_deltas_eta = [(query_time.to_pydatetime()-time_.to_pydatetime()) for time_ in all_df_times.loc[:,"eta_berth"] if not pd.isnull(time_)]
+    time_deltas_etd = [(query_time.to_pydatetime()-time_.to_pydatetime()) for time_ in all_df_times.loc[:,"etd_berth"] if not pd.isnull(time_)]
+
+    # consider both, eta and etd times
+    time_deltas = time_deltas_eta + time_deltas_etd
+
+    # convert the timedelta to absolute total seconds
+    time_deltas = [abs(delta.total_seconds()) for delta in time_deltas]
+
+    # consider only those time deltas, which are <= the determined threshold
+    # create a list of booleans
+    time_deltas_filtered = [delta <= delta_threshold for delta in time_deltas]
+
+    # booleans can be added/counted in Python by using sum()
+    counts = sum(time_deltas_filtered) # int
+    return counts
+
+def execute_sql_query_standalone(query, param={}, pooledConnection=None, model=None, command_type="query"):
+    """
+    execute an arbitrary query with a set of parameters, return the output and convert it to a list. 
+    when the pooled connection is rebuilt, it will be closed at the end of the function. 
+    """
+    rebuild_pooled_connection = pooledConnection is None
+
+    if rebuild_pooled_connection:
+        pooledConnection = getPoolConnection()
+
+    commands = pydapper.using(pooledConnection)
+    # participant_query = "SELECT participant_id, type FROM shipcall_participant_map WHERE shipcall_id=?shipcall_id?";
+
+    # creates a generator
+    try:
+        if command_type=="query":
+            if model is None:
+                schemas = commands.query(query, model=dict, param=param, buffered=False)
+            else:
+                schemas = commands.query(query, model=model, param=param, buffered=False)
+
+            # creates a list of results from the generator
+            schemas = [schema for schema in schemas]
+
+        elif command_type=="execute":
+            schemas = commands.execute(query, param=param)
+        elif command_type=="single":
+            sentinel = object()
+
+            # pulls a *single* row from the query. Typically, these queries require an ID within the param dictionary.
+            # when providing a model, such as model.Shipcall, the dataset is immediately translated into a data model.
+            schemas = commands.query_single_or_default(query, sentinel, param=param) if model is None else commands.query_single_or_default(query, sentinel, param=param, model=model)
+            if schemas is sentinel:
+                raise Exception("no such record")
+
+        else:
+            raise ValueError(command_type)
+        
+    finally: # if needed, ensure that the pooled connection is closed.
+        if rebuild_pooled_connection:
+            pooledConnection.close()
+    return schemas
+    
 class SQLHandler():
     """
     An object that reads SQL queries from the sql_connection and stores it in pandas DataFrames. The object can read all available tables
@@ -36,6 +111,15 @@ class SQLHandler():
         if read_all:
             self.read_all(self.all_schemas)
 
+    def execute_sql_query(self, sql_connection, query, param):
+        """
+        this method is best used in combination with a python context-manager, such as:
+        with mysql.connector.connect(**mysql_connection_data) as sql_connection:
+            schema = sql_handler.execute_sql_query(sql_connection, query)
+        """
+        schemas = execute_sql_query_standalone(query, param, pooledConnection=sql_connection)
+        return schemas
+
     def get_all_schemas_from_mysql(self):
         with self.sql_connection.cursor(buffered=True) as cursor:
             cursor.execute("SHOW TABLES")
@@ -50,7 +134,8 @@ class SQLHandler():
             'ship'->BreCal.schemas.model.Ship object
         """
         self.str_to_model_dict = {
-            "shipcall":Shipcall, "ship":Ship, "participant":Participant, "berth":Berth, "user":User, "times":Times
+            "shipcall":Shipcall, "ship":Ship, "participant":Participant, "berth":Berth, "user":User, "times":Times,
+            "shipcall_participant_map":ShipcallParticipantMap
         }
         return
 
@@ -70,12 +155,16 @@ class SQLHandler():
         data = [{k:v for k,v in zip(column_names, dat)} for dat in data]
 
         # 4.) build a dataframe from the respective data models (which ensures the correct data type)
+        df = self.build_df_from_data_and_name(data, table_name)
+        return df
+    
+    def build_df_from_data_and_name(self, data, table_name):
         data_model = self.str_to_model_dict.get(table_name)
         if data_model is not None:
-            df = pd.DataFrame([data_model(**dat) for dat in data])
+            df = pd.DataFrame([data_model(**dat) for dat in data], columns=list(data_model.__annotations__.keys()))
         else:
             df = pd.DataFrame([dat for dat in data])
-        return df
+        return df 
 
     def mysql_to_df(self, query, table_name):
         """provide an arbitrary sql query that should be read from a mysql server {sql_connection}. returns a pandas DataFrame with the obtained data"""
@@ -94,11 +183,7 @@ class SQLHandler():
 
         # 4.) build a dataframe from the respective data models (which ensures the correct data type)
         data_model = self.str_to_model_dict.get(table_name)
-        if data_model is not None:
-            df = pd.DataFrame([data_model(**dat) for dat in data])
-        else:
-            df = pd.DataFrame([dat for dat in data])
-        
+        df = self.build_df_from_data_and_name(data, table_name)
         if 'id' in df.columns:
             df = df.set_index('id', inplace=False) # avoid inplace updates, so the raw sql remains unchanged
         return df
@@ -332,6 +417,10 @@ class SQLHandler():
     
     def get_unique_ship_counts(self, all_df_times:pd.DataFrame, times_agency:pd.DataFrame, query:str, rounding:str="min", maximum_threshold=3):
         """given a dataframe of all agency times, get all unique ship counts, their values (datetime) and the string tags. returns a tuple (values,unique,counts)"""
+        # #deprecated!
+        import warnings
+        warnings.warn(f"SQLHandler.get_unique_ship_counts is deprecated. Instead, please use SQLHandler.count_synchronous_shipcall_times")
+
         # optional: rounding
         if rounding is not None:
             all_df_times.loc[:, query] = pd.to_datetime(all_df_times.loc[:, query]).dt.round(rounding) # e.g., 'min' ---  # correcting the error: 'AttributeError: Can only use .dt accessor with datetimelike values'
@@ -347,3 +436,7 @@ class SQLHandler():
         # get unique entries and counts
         counts = len(values) # unique, counts = np.unique(values, return_counts=True)
         return counts # (values, unique, counts)
+
+    def count_synchronous_shipcall_times(self, query_time:pd.Timestamp, all_df_times:pd.DataFrame, delta_threshold=900)->int:
+        """count all times entries, which are too close to the query_time. The {delta_threshold} determines the threshold. returns counts (int)"""
+        return get_synchronous_shipcall_times_standalone(query_time, all_df_times, delta_threshold)
diff --git a/src/server/BreCal/database/sql_queries.py b/src/server/BreCal/database/sql_queries.py
new file mode 100644
index 0000000..51a3dea
--- /dev/null
+++ b/src/server/BreCal/database/sql_queries.py
@@ -0,0 +1,418 @@
+import logging
+
+
+def create_sql_query_shipcall_get(options:dict)->str:
+    """
+    creates an SQL query, which selects all shipcalls from the mysql database.
+    the agency eta times are used to order the entries.
+
+    args:
+        options : dict. A dictionary, which must contains the 'past_days' key (int). Determines the range
+        by which shipcalls are filtered. 
+    """
+    query = ("SELECT s.id as id, ship_id, type, eta, voyage, etd, arrival_berth_id, departure_berth_id, tug_required, pilot_required, " +
+    "flags, s.pier_side, bunkering, replenishing_terminal, replenishing_lock, draft, tidal_window_from, " +
+    "tidal_window_to, rain_sensitive_cargo, recommended_tugs, anchored, moored_lock, canceled, evaluation, " +
+    "evaluation_message, evaluation_time, evaluation_notifications_sent, s.created as created, s.modified as modified, time_ref_point " +
+    "FROM shipcall s " +
+    "LEFT JOIN times t ON t.shipcall_id = s.id AND t.participant_type = 8 " +
+    "WHERE " +
+    "(type = 1 AND  " +
+    "((t.id IS NOT NULL AND t.eta_berth >= DATE(NOW() - INTERVAL %d DAY)) OR " +
+    "(eta >= DATE(NOW() - INTERVAL %d DAY)))) OR " +
+    "((type = 2 OR type = 3) AND " +
+    "((t.id IS NOT NULL AND t.etd_berth >= DATE(NOW() - INTERVAL %d DAY)) OR " +
+    "(etd >= DATE(NOW() - INTERVAL %d DAY)))) " +
+    "ORDER BY eta") % (options["past_days"], options["past_days"], options["past_days"], options["past_days"])
+
+    return query
+
+
+def create_sql_query_shipcall_post(schemaModel:dict)->str:
+    query = "INSERT INTO shipcall ("
+    isNotFirst = False
+    for key in schemaModel.keys():
+        if key == "id":
+            continue
+        if key == "participants":
+            continue
+        if key == "created":
+            continue
+        if key == "modified":
+            continue
+        if key == "evaluation":
+            continue
+        if key == "evaluation_message":
+            continue            
+        if key == "type_value":
+            continue            
+        if key == "evaluation_value":
+            continue
+        if isNotFirst:
+            query += ","
+        isNotFirst = True
+        query += key
+    query += ") VALUES ("
+    isNotFirst = False
+    for key in schemaModel.keys():
+        param_key = key
+        if key == "id":
+            continue
+        if key == "participants":
+            continue
+        if key == "created":
+            continue
+        if key == "modified":
+            continue
+        if key == "evaluation":
+            continue
+        if key == "evaluation_message":
+            continue
+        if key == "type":
+            param_key = "type_value"
+        if key == "type_value":
+            continue
+        if key == "evaluation":
+            param_key = "evaluation_value"
+        if key == "evaluation_value":
+            continue
+        if isNotFirst:
+            query += ","
+        isNotFirst = True
+        query += "?" + param_key + "?"
+    query += ")"
+    return query
+
+def create_sql_query_shipcall_put(schemaModel:dict)->str:
+    query = "UPDATE shipcall SET "
+    isNotFirst = False
+    for key in schemaModel.keys():
+        param_key = key
+        if key == "id":
+            continue
+        if key == "participants":
+            continue
+        if key == "created":
+            continue
+        if key == "modified":
+            continue
+        if key == "evaluation":
+            continue
+        if key == "evaluation_message":
+            continue
+        if key == "type":
+            param_key = "type_value"
+        if key == "type_value":
+            continue
+        if key == "evaluation":
+            param_key = "evaluation_value"
+        if key == "evaluation_value":
+            continue
+        if isNotFirst:
+                query += ", "
+        isNotFirst = True
+        query += key + " = ?" + param_key + "? "
+
+    query += "WHERE id = ?id?"
+    return query
+
+
+def create_sql_query_history_post()->str:
+    query = "INSERT INTO history (participant_id, shipcall_id, user_id, timestamp, eta, type, operation) VALUES (?pid?, ?scid?, ?uid?, CURRENT_TIMESTAMP, CURRENT_TIMESTAMP, 1, 1)"
+    return query
+
+def create_sql_query_history_put()->str:
+    query = "INSERT INTO history (participant_id, shipcall_id, user_id, timestamp, eta, type, operation) VALUES (?pid?, ?scid?, ?uid?, CURRENT_TIMESTAMP, CURRENT_TIMESTAMP, 1, 2)"
+    return query
+
+def create_sql_query_user_put(schemaModel:dict):
+    query = "UPDATE user SET "
+    isNotFirst = False
+    for key in schemaModel.keys():
+        if key == "id":
+            continue
+        if key == "old_password":
+            continue
+        if key == "new_password":
+            continue
+        if isNotFirst:
+            query += ", "
+        isNotFirst = True
+        query += key + " = ?" + key + "? "
+
+    query += "WHERE id = ?id?"
+    return query
+
+def create_sql_query_ship_post(schemaModel:dict):
+    query = "INSERT INTO ship ("
+    isNotFirst = False
+    for key in schemaModel.keys():
+        if key == "id":
+            continue
+        if key == "created":
+            continue
+        if key == "modified":
+            continue
+        if isNotFirst:
+            query += ","
+        isNotFirst = True
+        query += key
+    query += ") VALUES ("
+    isNotFirst = False
+    for key in schemaModel.keys():
+        if key == "id":
+            continue
+        if key == "created":
+            continue
+        if key == "modified":
+            continue
+        if isNotFirst:
+            query += ","
+        isNotFirst = True
+        query += "?" + key + "?"
+    query += ")"
+    return query
+
+def create_sql_query_ship_put(schemaModel:dict):
+    query = "UPDATE ship SET "
+    isNotFirst = False
+    for key in schemaModel.keys():
+        if key == "id":
+            continue
+        if key == "created":
+            continue
+        if key == "modified":
+            continue
+        if isNotFirst:
+                query += ", "
+        isNotFirst = True
+        query += key + " = ?" + key + "? "
+
+    query += "WHERE id = ?id?"
+    return query
+
+
+
+class SQLQuery():
+    """
+    This class provides quick access to different SQL query functions, which creates default queries for the BreCal package.
+    Each method is callable without initializing the SQLQuery object. 
+
+    Example:
+        SQLQuery.get_berths()
+
+    When the data violates one of the rules, a marshmallow.ValidationError is raised, which details the issues. 
+    """
+    def __init__(self) -> None:
+        pass
+
+    @staticmethod
+    def get_berth()->str:
+        query = "SELECT id, name, `lock`, owner_id, authority_id, created, modified, deleted FROM berth WHERE deleted = 0 ORDER BY name"
+        return query
+
+    @staticmethod
+    def get_history()->str:
+        query = "SELECT id, participant_id, shipcall_id, timestamp, eta, type, operation FROM history WHERE shipcall_id = ?shipcallid?"
+        return query
+    
+    @staticmethod
+    def get_user()->str:
+        query = "SELECT id, participant_id, first_name, last_name, user_name, user_email, user_phone, password_hash, " +\
+            "api_key, notify_email, notify_whatsapp, notify_signal, notify_popup, created, modified FROM user " +\
+            "WHERE user_name = ?username? OR user_email = ?username?"
+        return query
+    
+    @staticmethod
+    def get_notifications()->str:
+        query = "SELECT id, shipcall_id, level, type, message, created, modified FROM notification " + \
+            "WHERE shipcall_id = ?scid?"
+        return query
+    
+    @staticmethod
+    def get_participant_by_user_id()->str:
+        query = "SELECT p.id as id, p.name as name, p.street as street, p.postal_code as postal_code, p.city as city, p.type as type, p.flags as flags, p.created as created, p.modified as modified, p.deleted as deleted FROM  participant p INNER JOIN user u WHERE u.participant_id = p.id and u.id = ?userid?"
+        return query
+    
+    @staticmethod
+    def get_participants()->str:
+        query = "SELECT id, name, street, postal_code, city, type, flags, created, modified, deleted FROM participant p ORDER BY p.name"
+        return query
+    
+    @staticmethod
+    def get_shipcalls(options:dict={'past_days':3})->str:
+        # a pytest proves this method to be identical to create_sql_query_shipcall_get(options)
+        assert 'past_days' in list(options.keys()), f"there must be a key 'past_days' in the options, which determines, how recent the returned list of shipcalls shall be." # part of a pytest.raises
+        past_days = options['past_days']
+
+        query = ("SELECT s.id as id, ship_id, type, eta, voyage, etd, arrival_berth_id, departure_berth_id, tug_required, pilot_required, " + \
+            "flags, s.pier_side, bunkering, replenishing_terminal, replenishing_lock, draft, tidal_window_from, " + \
+            "tidal_window_to, rain_sensitive_cargo, recommended_tugs, anchored, moored_lock, canceled, evaluation, " + \
+            "evaluation_message, evaluation_time, evaluation_notifications_sent, s.created as created, s.modified as modified, time_ref_point " + \
+            "FROM shipcall s " + \
+            "LEFT JOIN times t ON t.shipcall_id = s.id AND t.participant_type = 8 " + \
+            "WHERE " + \
+            "(type = 1 AND  " + \
+            f"((t.id IS NOT NULL AND t.eta_berth >= DATE(NOW() - INTERVAL {past_days} DAY)) OR " + \
+            f"(eta >= DATE(NOW() - INTERVAL {past_days} DAY)))) OR " + \
+            "((type = 2 OR type = 3) AND " + \
+            f"((t.id IS NOT NULL AND t.etd_berth >= DATE(NOW() - INTERVAL {past_days} DAY)) OR " + \
+            f"(etd >= DATE(NOW() - INTERVAL {past_days} DAY)))) " + \
+            "ORDER BY eta")
+        return query
+    
+    @staticmethod
+    def get_ships()->str:
+        query = "SELECT id, name, imo, callsign, participant_id, length, width, is_tug, bollard_pull, eni, created, modified, deleted FROM ship ORDER BY name"
+        return query
+    
+    @staticmethod
+    def get_times()->str:
+        query = "SELECT id, eta_berth, eta_berth_fixed, etd_berth, etd_berth_fixed, lock_time, lock_time_fixed, " + \
+            "zone_entry, zone_entry_fixed, operations_start, operations_end, remarks, shipcall_id, participant_id, " + \
+            "berth_id, berth_info, pier_side, participant_type, created, modified, ata, atd, eta_interval_end, etd_interval_end FROM times " + \
+            "WHERE times.shipcall_id = ?scid?"
+        return query
+    
+    @staticmethod
+    def get_user_by_id():
+        query = "SELECT * FROM user where id = ?id?"
+        return query
+    
+    @staticmethod
+    def get_user_put(schemaModel:dict):
+        # a pytest proves this method to be identical to create_sql_query_user_put(schemaModel)
+        prefix = "UPDATE user SET "
+        suffix = "WHERE id = ?id?"
+        center = [f"{key} = ?{key}? " for key in schemaModel.keys() if key not in ["id", "old_password", "new_password"]]
+
+        query = prefix + ", ".join(center) + suffix
+        return query
+
+    @staticmethod
+    def get_update_user_password()->str:
+        query = "UPDATE user SET password_hash = ?password_hash? WHERE id = ?id?"
+        return query
+
+    @staticmethod
+    def get_participants()->str:
+        query = "SELECT participant_id, type FROM shipcall_participant_map WHERE shipcall_id=?shipcall_id?"
+        return query
+    
+    @staticmethod
+    def get_shipcall_post(schemaModel:dict)->str:
+        # a pytest proves this method to be identical to create_sql_query_shipcall_post(schemaModel)
+
+        param_keys = {key:key for key in schemaModel.keys()}
+        param_keys["type"] = "type_value"
+        param_keys["evaluation"] = "evaluation_value"
+
+        prefix = "INSERT INTO shipcall ("
+        bridge = ") VALUES ("
+        suffix = ")"
+
+        stage1 = ",".join([key for key in schemaModel.keys() if not key in ["id","participants","created","modified","evaluation","evaluation_message","type_value","evaluation_value"]])
+        stage2 = ",".join([f"?{param_keys.get(key)}?" for key in schemaModel.keys() if not key in ["id","participants","created","modified","evaluation","evaluation_message","type_value","evaluation_value"]])
+
+        query = prefix+stage1+bridge+stage2+suffix
+        return query
+
+    @staticmethod
+    def get_last_insert_id()->str:
+        query = "select last_insert_id()"
+        return query
+    
+    @staticmethod
+    def get_shipcall_post_last_insert_id()->str:
+        """alias function. May be deleted soon"""
+        query = SQLQuery.get_last_insert_id()
+        return query
+    
+    @staticmethod
+    def get_shipcall_post_update_shipcall_participant_map()->str:
+        query = "INSERT INTO shipcall_participant_map (shipcall_id, participant_id, type) VALUES (?shipcall_id?, ?participant_id?, ?type?)"
+        return query
+    
+    @staticmethod
+    def create_sql_query_history_post()->str:
+        query = create_sql_query_history_post()
+        return query
+    
+    @staticmethod
+    def get_shipcall_by_id()->str:
+        query = "SELECT * FROM shipcall where id = ?id?"
+        return query
+    
+    @staticmethod
+    def get_shipcall_put(schemaModel:dict)->str:
+        # a pytest proves this method to be identical to create_sql_query_shipcall_put(schemaModel)
+        param_keys = {key:key for key in schemaModel.keys()}
+        param_keys["type"] = "type_value"
+        param_keys["evaluation"] = "evaluation_value"
+
+        prefix = "UPDATE shipcall SET "
+        suffix = "WHERE id = ?id?"
+        body = ", ".join([f"{key} = ?{param_keys.get(key)}? " for key in schemaModel.keys() if key not in ["id", "participants", "created", "modified", "evaluation", "evaluation_message", "type_value", "evaluation_value"]])
+
+        query = prefix + body + suffix
+        return query
+    
+    @staticmethod
+    def get_shipcall_participant_map_by_shipcall_id()->str:
+        query = "SELECT id, participant_id, type FROM shipcall_participant_map where shipcall_id = ?id?"
+        return query
+
+    @staticmethod
+    def get_shipcall_participant_map_delete_by_id()->str:
+        query = "DELETE FROM shipcall_participant_map WHERE id = ?existing_id?"
+        return query
+
+    @staticmethod
+    def create_sql_query_history_put()->str:
+        query = create_sql_query_history_put()
+        return query
+
+    @staticmethod
+    def get_ship_post(schemaModel:dict)->str:
+        # a pytest proves this method to be identical to create_sql_query_ship_post(schemaModel)
+        prefix = "INSERT INTO ship ("
+        suffix = ")"
+        bridge = ") VALUES ("
+
+        stage1 = ",".join([key for key in schemaModel.keys() if not key in ["id", "created", "modified"]])
+        stage2 = ",".join([f"?{key}?" for key in schemaModel.keys() if not key in ["id", "created", "modified"]])
+
+        query = prefix + stage1 + bridge + stage2 + suffix
+        return query
+
+    @staticmethod
+    def get_ship_put(schemaModel:dict)->str:
+        # a pytest proves this method to be identical to create_sql_query_ship_put(schemaModel)
+        prefix = "UPDATE ship SET "
+        suffix = "WHERE id = ?id?"
+        body = ", ".join([f"{key} = ?{key}? " for key in schemaModel.keys() if not key in ["id","created","modified"]])
+
+        query = prefix + body + suffix
+        return query
+
+    @staticmethod
+    def get_ship_delete_by_id()->str:
+        query = "UPDATE ship SET deleted = 1 WHERE id = ?id?"
+        return query
+    
+    @staticmethod
+    def get_notification_post()->str:
+        raise NotImplementedError()
+        # #TODO: this query is wrong and just a proxy for a POST request
+        query = "INSERT INTO shipcall_participant_map (shipcall_id, participant_id, type) VALUES (?shipcall_id?, ?participant_id?, ?type?)"
+        return query
+    
+    @staticmethod
+    def get_shipcall_put_notification_state()->str:
+        raise NotImplementedError()
+        # #TODO: use evaluation_notifications_sent here and consider only the shipcall_id
+        # #TODO: query
+        query = ...
+        return query
+
+
diff --git a/src/server/BreCal/database/sql_utils.py b/src/server/BreCal/database/sql_utils.py
new file mode 100644
index 0000000..5780ace
--- /dev/null
+++ b/src/server/BreCal/database/sql_utils.py
@@ -0,0 +1,14 @@
+from BreCal.database.sql_handler import execute_sql_query_standalone
+import datetime
+
+def get_user_data_for_id(user_id:int, expiration_time:int=90):
+    """debugging function, which is useful to pull user_data from the database, which may be used to create stub data and unit tests"""
+    query = "SELECT * FROM user where id = ?id?"
+    pdata = execute_sql_query_standalone(query=query, param={"id":user_id})
+    pdata = pdata[0] if len(pdata)>0 else None
+    assert pdata is not None, f"could not find user with id {user_id}"
+
+    user_data = {k:v for k,v in pdata.items() if k in ['id','participant_id','first_name','last_name','user_name','user_phone','user_email']}
+    user_data["exp"] = (datetime.datetime.now()+datetime.timedelta(minutes=expiration_time)).timestamp()
+    return user_data
+
diff --git a/src/server/BreCal/database/update_database.py b/src/server/BreCal/database/update_database.py
index 0e5e5ac..395f725 100644
--- a/src/server/BreCal/database/update_database.py
+++ b/src/server/BreCal/database/update_database.py
@@ -34,6 +34,7 @@ def update_shipcall_in_mysql_database(sql_connection, shipcall:Shipcall, relevan
 
 def build_mysql_query_to_update_shipcall(shipcall, relevant_keys:list):
     """builds a mysql query, which updates the shipcall table. In particular, the provided shipcall will be updated for each key in {relevant_keys}"""
+    # #TODO: refactor into SQLQuery
     schemaModel = shipcall.__dict__
 
     # prepare prefix and suffix. Then build the body of the query
@@ -68,7 +69,6 @@ def evaluate_shipcall_state(mysql_connector_instance, shipcall_id:int=None, debu
             with mysql.connector.connect(**mysql_connection_data) as mysql_connector_instance:
                 evaluate_shipcall_state(mysql_connector_instance)
     returns None
-
     """
     sql_handler = SQLHandler(sql_connection=mysql_connector_instance, read_all=True)
     vr = ValidationRules(sql_handler)
diff --git a/src/server/BreCal/impl/berths.py b/src/server/BreCal/impl/berths.py
index 9087856..0ed2ca9 100644
--- a/src/server/BreCal/impl/berths.py
+++ b/src/server/BreCal/impl/berths.py
@@ -4,6 +4,7 @@ import pydapper
 
 from ..schemas import model
 from .. import local_db
+from BreCal.database.sql_queries import SQLQuery
 
 def GetBerths(token):
     """
@@ -13,6 +14,8 @@ def GetBerths(token):
     try:
         pooledConnection = local_db.getPoolConnection()
         commands = pydapper.using(pooledConnection)
+        # query = SQLQuery.get_berth()
+        # data = commands.query(query, model=model.Berth)
         data = commands.query("SELECT id, name, `lock`, owner_id, authority_id, created, modified, deleted FROM berth WHERE deleted = 0 ORDER BY name", model=model.Berth)
         return json.dumps(data, default=model.obj_dict), 200, {'Content-Type': 'application/json; charset=utf-8'}
 
diff --git a/src/server/BreCal/impl/history.py b/src/server/BreCal/impl/history.py
index f408001..53f159c 100644
--- a/src/server/BreCal/impl/history.py
+++ b/src/server/BreCal/impl/history.py
@@ -7,6 +7,7 @@ from ..schemas import model
 from ..schemas.model import History
 
 from .. import local_db
+from BreCal.database.sql_queries import SQLQuery
 
 def GetHistory(options):
 
@@ -20,6 +21,8 @@ def GetHistory(options):
         commands = pydapper.using(pooledConnection)
 
         if "shipcall_id" in options and options["shipcall_id"]:
+            # query = SQLQuery.get_history()
+            # data = commands.query(query, model=History.from_query_row, param={"shipcallid" : options["shipcall_id"]})
             data = commands.query("SELECT id, participant_id, shipcall_id, timestamp, eta, type, operation FROM history WHERE shipcall_id = ?shipcallid?",
                                   model=History.from_query_row,
                                   param={"shipcallid" : options["shipcall_id"]})
diff --git a/src/server/BreCal/impl/login.py b/src/server/BreCal/impl/login.py
index 21b46a6..66e709b 100644
--- a/src/server/BreCal/impl/login.py
+++ b/src/server/BreCal/impl/login.py
@@ -6,6 +6,7 @@ import bcrypt
 from ..schemas import model
 from .. import local_db
 from ..services import jwt_handler
+from BreCal.database.sql_queries import SQLQuery
 
 def GetUser(options):
 
@@ -14,11 +15,13 @@ def GetUser(options):
             hash = bcrypt.hashpw(options["password"].encode('utf-8'), bcrypt.gensalt( 12 )).decode('utf8')
             pooledConnection = local_db.getPoolConnection()
             commands = pydapper.using(pooledConnection)
+            # query = SQLQuery.get_user()
+            # data = commands.query(query, model=model.User, param={"username" : options["username"]})
             data = commands.query("SELECT id, participant_id, first_name, last_name, user_name, user_email, user_phone, password_hash, " +
                                   "api_key, notify_email, notify_whatsapp, notify_signal, notify_popup, created, modified FROM user " +
                                   "WHERE user_name = ?username? OR user_email = ?username?",
                                   model=model.User, param={"username" : options["username"]})
-            # print(data)
+            
             if len(data) == 1:
                 if bcrypt.checkpw(options["password"].encode("utf-8"), bytes(data[0].password_hash, "utf-8")):
                     result = {
diff --git a/src/server/BreCal/impl/notifications.py b/src/server/BreCal/impl/notifications.py
index 67619ab..2f0014b 100644
--- a/src/server/BreCal/impl/notifications.py
+++ b/src/server/BreCal/impl/notifications.py
@@ -4,6 +4,7 @@ import pydapper
 
 from ..schemas import model
 from .. import local_db
+from BreCal.database.sql_queries import SQLQuery
 
 def GetNotifications(options):
     """
@@ -16,6 +17,8 @@ def GetNotifications(options):
 
         pooledConnection = local_db.getPoolConnection()
         commands = pydapper.using(pooledConnection)
+        # query = SQLQuery.get_notifications()
+        # data = commands.query(query, model=model.Notification.from_query_row, param={"scid" : options["shipcall_id"]})
         data = commands.query("SELECT id, shipcall_id, level, type, message, created, modified FROM notification " +
                               "WHERE shipcall_id = ?scid?", model=model.Notification.from_query_row, param={"scid" : options["shipcall_id"]})
         pooledConnection.close()
diff --git a/src/server/BreCal/impl/participant.py b/src/server/BreCal/impl/participant.py
index aad0def..7f9cc48 100644
--- a/src/server/BreCal/impl/participant.py
+++ b/src/server/BreCal/impl/participant.py
@@ -4,6 +4,7 @@ import pydapper
 
 from ..schemas import model
 from .. import local_db
+from BreCal.database.sql_queries import SQLQuery
 
 def GetParticipant(options):
     """
@@ -16,8 +17,10 @@ def GetParticipant(options):
         pooledConnection = local_db.getPoolConnection()
         commands = pydapper.using(pooledConnection)
         if "user_id" in options and options["user_id"]:
+            # query = SQLQuery.get_participant_by_user_id()
             data = commands.query("SELECT p.id as id, p.name as name, p.street as street, p.postal_code as postal_code, p.city as city, p.type as type, p.flags as flags, p.created as created, p.modified as modified, p.deleted as deleted FROM  participant p INNER JOIN user u WHERE u.participant_id = p.id and u.id = ?userid?", model=model.Participant, param={"userid" : options["user_id"]})
         else:
+            # query = SQLQuery.get_participants()
             data = commands.query("SELECT id, name, street, postal_code, city, type, flags, created, modified, deleted FROM participant p ORDER BY p.name", model=model.Participant)
 
         return json.dumps(data, default=model.obj_dict), 200, {'Content-Type': 'application/json; charset=utf-8'}
diff --git a/src/server/BreCal/impl/shipcalls.py b/src/server/BreCal/impl/shipcalls.py
index 59f9311..83385cf 100644
--- a/src/server/BreCal/impl/shipcalls.py
+++ b/src/server/BreCal/impl/shipcalls.py
@@ -8,6 +8,8 @@ from .. import local_db
 from ..services.auth_guard import check_jwt
 
 from BreCal.database.update_database import evaluate_shipcall_state
+from BreCal.database.sql_queries import create_sql_query_shipcall_get, create_sql_query_shipcall_post, create_sql_query_shipcall_put, create_sql_query_history_post, create_sql_query_history_put, SQLQuery
+from marshmallow import Schema, fields, ValidationError
 
 def GetShipcalls(options):
     """
@@ -18,23 +20,14 @@ def GetShipcalls(options):
 
         pooledConnection = local_db.getPoolConnection()
         commands = pydapper.using(pooledConnection)
-        query = ("SELECT s.id as id, ship_id, type, eta, voyage, etd, arrival_berth_id, departure_berth_id, tug_required, pilot_required, " +
-		"flags, s.pier_side, bunkering, replenishing_terminal, replenishing_lock, draft, tidal_window_from, " +
-        "tidal_window_to, rain_sensitive_cargo, recommended_tugs, anchored, moored_lock, canceled, evaluation, " +
-        "evaluation_message, evaluation_time, evaluation_notifications_sent, s.created as created, s.modified as modified, time_ref_point " +
-        "FROM shipcall s " +
-        "LEFT JOIN times t ON t.shipcall_id = s.id AND t.participant_type = 8 " +
-        "WHERE " +
-        "(type = 1 AND  " +
-        "((t.id IS NOT NULL AND t.eta_berth >= DATE(NOW() - INTERVAL %d DAY)) OR " +
-        "(eta >= DATE(NOW() - INTERVAL %d DAY)))) OR " +
-        "((type = 2 OR type = 3) AND " +
-        "((t.id IS NOT NULL AND t.etd_berth >= DATE(NOW() - INTERVAL %d DAY)) OR " +
-        "(etd >= DATE(NOW() - INTERVAL %d DAY)))) " +
-        "ORDER BY eta") % (options["past_days"], options["past_days"], options["past_days"], options["past_days"])
+        # query = SQLQuery.get_shipcalls(options)
+        query = create_sql_query_shipcall_get(options)
 
         data = commands.query(query, model=model.Shipcall.from_query_row, buffered=True)
         for shipcall in data:
+            # participant_query = SQLQuery.get_participants()
+            # participants = commands.query(participant_query, model=dict, param={"shipcall_id" : shipcall.id}, buffered=False)
+            # for record in participants:
             participant_query = "SELECT participant_id, type FROM shipcall_participant_map WHERE shipcall_id=?shipcall_id?";
             for record in commands.query(participant_query, model=dict, param={"shipcall_id" : shipcall.id}, buffered=False):
                 # model.Participant_Assignment = model.Participant_Assignment()
@@ -58,18 +51,29 @@ def GetShipcalls(options):
 
 def PostShipcalls(schemaModel):
     """
+    This function *executes* a post-request for shipcalls. The function is accessible as part of an API route. 
+    
+    The common sequence is:
+        a) issue a request to the Flask API
+        b) BreCal.api.shipcalls.PostShipcalls, to verify the incoming request (which includes an authentification guard)
+        c) BreCal.impl.shipcalls.PostShipcalls, to execute the incoming request
 
     :param schemaModel: The deserialized dict of the request
+    e.g.,
+        {
+            'ship_id': 1, 'type': 1, 'eta': datetime.datetime(2023, 7, 23, 7, 18, 19), 
+            'voyage': '43B', 'tug_required': False, 'pilot_required': True, 'flags': 0, 
+            'pier_side': False, 'bunkering': True, 'recommended_tugs': 2, 'type_value': 1, 'evaluation_value': 0}
+        }
     """
 
-    # TODO: Validate the upload data
-
     # This creates a *new* entry
     try:
 
         pooledConnection = local_db.getPoolConnection()
         commands = pydapper.using(pooledConnection)
 
+        # query = SQLQuery.get_shipcall_post(schemaModel) # create_sql_query_shipcall_post(schemaModel)
         query = "INSERT INTO shipcall ("
         isNotFirst = False
         for key in schemaModel.keys():
@@ -122,12 +126,15 @@ def PostShipcalls(schemaModel):
             isNotFirst = True
             query += "?" + param_key + "?"
         query += ")"
-
         commands.execute(query, schemaModel)
+
+        # lquery = SQLQuery.get_shipcall_post_last_insert_id()
+        # new_id = commands.execute_scalar(lquery)
         new_id = commands.execute_scalar("select last_insert_id()")
 
         # add participant assignments if we have a list of participants
         if 'participants' in schemaModel:
+            # pquery = SQLQuery.get_shipcall_post_update_shipcall_participant_map()
             pquery = "INSERT INTO shipcall_participant_map (shipcall_id, participant_id, type) VALUES (?shipcall_id?, ?participant_id?, ?type?)"
             for participant_assignment in schemaModel["participants"]:
                 commands.execute(pquery, param={"shipcall_id" : new_id, "participant_id" : participant_assignment["participant_id"], "type" : participant_assignment["type"]})
@@ -138,10 +145,16 @@ def PostShipcalls(schemaModel):
         # save history data
         # TODO: set ETA properly
         user_data = check_jwt()
+        # query = SQLQuery.create_sql_query_history_post()
         query = "INSERT INTO history (participant_id, shipcall_id, user_id, timestamp, eta, type, operation) VALUES (?pid?, ?scid?, ?uid?, CURRENT_TIMESTAMP, CURRENT_TIMESTAMP, 1, 1)"
         commands.execute(query, {"scid" : new_id, "pid" : user_data["participant_id"], "uid" : user_data["id"]})
 
         return json.dumps({"id" : new_id}), 201, {'Content-Type': 'application/json; charset=utf-8'}
+        
+    except ValidationError as ex:
+        logging.error(ex)
+        print(ex)
+        return json.dumps({"message":f"bad format. \nError Messages: {ex.messages}. \nValid Data: {ex.valid_data}"}), 400
 
     except Exception as ex:
         logging.error(traceback.format_exc())
@@ -168,14 +181,19 @@ def PutShipcalls(schemaModel):
         pooledConnection = local_db.getPoolConnection()
         commands = pydapper.using(pooledConnection)
 
+        user_data = check_jwt()
+
         # test if object to update is found
 
         sentinel = object()
+        # query = SQLQuery.get_shipcall_by_id()
+        # theshipcall = commands.query_single_or_default(query, sentinel, param={"id" : schemaModel["id"]})
         theshipcall = commands.query_single_or_default("SELECT * FROM shipcall where id = ?id?", sentinel, param={"id" : schemaModel["id"]})
         if theshipcall is sentinel:
             pooledConnection.close()
             return json.dumps("no such record"), 404, {'Content-Type': 'application/json; charset=utf-8'}
 
+        # query = SQLQuery.get_shipcall_put(schemaModel)
         query = "UPDATE shipcall SET "
         isNotFirst = False
         for key in schemaModel.keys():
@@ -206,8 +224,10 @@ def PutShipcalls(schemaModel):
             query += key + " = ?" + param_key + "? "
 
         query += "WHERE id = ?id?"
+
         affected_rows = commands.execute(query, param=schemaModel)
 
+        # pquery = SQLQuery.get_shipcall_participant_map_by_shipcall_id()
         pquery = "SELECT id, participant_id, type FROM shipcall_participant_map where shipcall_id = ?id?"
         pdata = commands.query(pquery,param={"id" : schemaModel["id"]}) # existing list of assignments
 
@@ -220,6 +240,7 @@ def PutShipcalls(schemaModel):
                     found_participant = True
                     break
             if not found_participant:
+                # nquery = SQLQuery.get_shipcall_post_update_shipcall_participant_map()
                 nquery = "INSERT INTO shipcall_participant_map (shipcall_id, participant_id, type) VALUES (?shipcall_id?, ?participant_id?, ?type?)"
                 commands.execute(nquery, param={"shipcall_id" : schemaModel["id"], "participant_id" : participant_assignment["participant_id"], "type" : participant_assignment["type"]})
 
@@ -231,19 +252,22 @@ def PutShipcalls(schemaModel):
                     found_participant = True
                     break;
             if not found_participant:
+                # dquery = SQLQuery.get_shipcall_participant_map_delete_by_id()
                 dquery = "DELETE FROM shipcall_participant_map WHERE id = ?existing_id?"
                 commands.execute(dquery, param={"existing_id" : elem["id"]})
 
-        # apply 'Traffic Light' evaluation to obtain 'GREEN', 'YELLOW' or 'RED' evaluation state. The function internally updates the mysql database
-        # evaluate_shipcall_state(mysql_connector_instance=pooledConnection, shipcall_id=schemaModel["id"]) # schemaModel["id"] refers to the shipcall id
-
         # save history data
         # TODO: set ETA properly
-        user_data = check_jwt()
+        # query = SQLQuery.create_sql_query_history_put()
         query = "INSERT INTO history (participant_id, shipcall_id, user_id, timestamp, eta, type, operation) VALUES (?pid?, ?scid?, ?uid?, CURRENT_TIMESTAMP, CURRENT_TIMESTAMP, 1, 2)"
         commands.execute(query, {"scid" : schemaModel["id"], "pid" : user_data["participant_id"], "uid" : user_data["id"]})
 
         return json.dumps({"id" : schemaModel["id"]}), 200
+        
+    except ValidationError as ex:
+        logging.error(ex)
+        print(ex)
+        return json.dumps({"message":f"bad format. \nError Messages: {ex.messages}. \nValid Data: {ex.valid_data}"}), 400
 
     except Exception as ex:
         logging.error(traceback.format_exc())
diff --git a/src/server/BreCal/impl/ships.py b/src/server/BreCal/impl/ships.py
index b0b0b94..0733071 100644
--- a/src/server/BreCal/impl/ships.py
+++ b/src/server/BreCal/impl/ships.py
@@ -4,6 +4,7 @@ import pydapper
 
 from ..schemas import model
 from .. import local_db
+from BreCal.database.sql_queries import SQLQuery
 
 def GetShips(token):
     """
@@ -14,6 +15,8 @@ def GetShips(token):
 
         pooledConnection = local_db.getPoolConnection()
         commands = pydapper.using(pooledConnection)
+        # query = SQLQuery.get_ships()
+        # data = commands.query(query, model=model.Ship)
         data = commands.query("SELECT id, name, imo, callsign, participant_id, length, width, is_tug, bollard_pull, eni, created, modified, deleted FROM ship ORDER BY name", model=model.Ship)
 
         return json.dumps(data, default=model.obj_dict), 200, {'Content-Type': 'application/json; charset=utf-8'}
@@ -46,6 +49,7 @@ def PostShip(schemaModel):
         pooledConnection = local_db.getPoolConnection()
         commands = pydapper.using(pooledConnection)
 
+        # query = SQLQuery.create_sql_query_ship_post(schemaModel)
         query = "INSERT INTO ship ("
         isNotFirst = False
         for key in schemaModel.keys():
@@ -75,6 +79,8 @@ def PostShip(schemaModel):
         query += ")"
 
         commands.execute(query, schemaModel)
+        # nquery = SQLQuery.get_last_insert_id()
+        # new_id = commands.execute_scalar(nquery)
         new_id = commands.execute_scalar("select last_insert_id()")
 
         pooledConnection.close()
@@ -100,6 +106,7 @@ def PutShip(schemaModel):
         pooledConnection = local_db.getPoolConnection()
         commands = pydapper.using(pooledConnection)
 
+        # query = SQLQuery.create_sql_query_ship_put(schemaModel)
         query = "UPDATE ship SET "
         isNotFirst = False
         for key in schemaModel.keys():
@@ -140,6 +147,8 @@ def DeleteShip(options):
 
         pooledConnection = local_db.getPoolConnection()
         commands = pydapper.using(pooledConnection)
+        # query = SQLQuery.get_ship_delete_by_id()
+        # affected_rows = commands.execute(query, param={"id" : options["id"]})
         affected_rows = commands.execute("UPDATE ship SET deleted = 1 WHERE id = ?id?", param={"id" : options["id"]})
 
         pooledConnection.close()
diff --git a/src/server/BreCal/impl/times.py b/src/server/BreCal/impl/times.py
index 1f16574..8c9f0e8 100644
--- a/src/server/BreCal/impl/times.py
+++ b/src/server/BreCal/impl/times.py
@@ -6,6 +6,7 @@ import pydapper
 from ..schemas import model
 from .. import local_db
 from ..services.auth_guard import check_jwt
+from BreCal.database.sql_queries import SQLQuery
 
 from BreCal.database.update_database import evaluate_shipcall_state
 
@@ -20,6 +21,8 @@ def GetTimes(options):
 
         pooledConnection = local_db.getPoolConnection()
         commands = pydapper.using(pooledConnection)
+        # query = SQLQuery.get_times()
+        # data = commands.query(query, model=model.Times, param={"scid" : options["shipcall_id"]})
         data = commands.query("SELECT id, eta_berth, eta_berth_fixed, etd_berth, etd_berth_fixed, lock_time, lock_time_fixed, " +
                               "zone_entry, zone_entry_fixed, operations_start, operations_end, remarks, shipcall_id, participant_id, " +
                               "berth_id, berth_info, pier_side, participant_type, created, modified, ata, atd, eta_interval_end, etd_interval_end FROM times " +
diff --git a/src/server/BreCal/impl/user.py b/src/server/BreCal/impl/user.py
index cd79f89..733998c 100644
--- a/src/server/BreCal/impl/user.py
+++ b/src/server/BreCal/impl/user.py
@@ -5,6 +5,7 @@ import bcrypt
 
 from ..schemas import model
 from .. import local_db
+from BreCal.database.sql_queries import SQLQuery, create_sql_query_user_put
 
 def PutUser(schemaModel):
     """
@@ -21,13 +22,21 @@ def PutUser(schemaModel):
         # test if object to update is found
 
         sentinel = object()
+        # query = SQLQuery.get_user_by_id()
+        # theuser = commands.query_single_or_default(query, sentinel, param={"id" : schemaModel["id"]}, model=model.User)
         theuser = commands.query_single_or_default("SELECT * FROM user where id = ?id?", sentinel, param={"id" : schemaModel["id"]}, model=model.User)
         if theuser is sentinel:
             pooledConnection.close()
+            # #TODO: result = {"message":"no such record"} -> json.dumps
             return json.dumps("no such record"), 404, {'Content-Type': 'application/json; charset=utf-8'}
 
         # see if we need to update public fields
+        # #TODO_determine: this filter blocks Put-Requests, which update the 'notify_email', 'notify_whatsapp', 'notify_signal', 'notify_popup' fields
+        # should this be refactored?
+        # Also, what about the 'user_name'?
+        # 'participant_id' would also not trigger an update in isolation
         if "first_name" in schemaModel or "last_name" in schemaModel or "user_phone" in schemaModel or "user_email" in schemaModel:
+            # query = SQLQuery.get_user_put(schemaModel)
             query = "UPDATE user SET "
             isNotFirst = False
             for key in schemaModel.keys():
@@ -49,6 +58,7 @@ def PutUser(schemaModel):
         if "old_password" in schemaModel and schemaModel["old_password"] and "new_password" in schemaModel and schemaModel["new_password"]:
                 if bcrypt.checkpw(schemaModel["old_password"].encode("utf-8"), bytes(theuser.password_hash, "utf-8")): # old pw matches
                     password_hash = bcrypt.hashpw(schemaModel["new_password"].encode('utf-8'), bcrypt.gensalt( 12 )).decode('utf8')
+                    # query = SQLQuery.get_update_user_password()
                     query = "UPDATE user SET password_hash = ?password_hash? WHERE id = ?id?"
                     commands.execute(query, param={"password_hash" : password_hash, "id" : schemaModel["id"]})
                 else:
diff --git a/src/server/BreCal/local_db.py b/src/server/BreCal/local_db.py
index 85dff68..330bc13 100644
--- a/src/server/BreCal/local_db.py
+++ b/src/server/BreCal/local_db.py
@@ -7,16 +7,16 @@ import sys
 
 config_path = None
 
-def initPool(instancePath):
+def initPool(instancePath, connection_filename="connection_data_devel.json"):
     try:
         global config_path
         if(config_path == None):
-            config_path = os.path.join(instancePath,'../../../secure/connection_data_devel.json');
+            config_path = os.path.join(instancePath,f'../../../secure/{connection_filename}') #connection_data_devel.json');
 
         print (config_path)
 
         if not os.path.exists(config_path):
-            print ('cannot find ' + config_path)
+            print ('cannot find ' + os.path.abspath(config_path))
             print("instance path", instancePath)
             sys.exit(1)
 
@@ -39,4 +39,4 @@ def getPoolConnection():
     global config_path
     f = open(config_path);
     connection_data = json.load(f)
-    return mysql.connector.connect(**connection_data)
\ No newline at end of file
+    return mysql.connector.connect(**connection_data)
diff --git a/src/server/BreCal/schemas/model.py b/src/server/BreCal/schemas/model.py
index bf157aa..92232e2 100644
--- a/src/server/BreCal/schemas/model.py
+++ b/src/server/BreCal/schemas/model.py
@@ -1,5 +1,5 @@
 from dataclasses import field, dataclass
-from marshmallow import Schema, fields, post_load, INCLUDE, ValidationError
+from marshmallow import Schema, fields, INCLUDE, ValidationError, validate, validates, post_load
 from marshmallow.fields import Field
 from marshmallow_enum import EnumField
 from enum import IntEnum
@@ -9,6 +9,11 @@ from typing import List
 
 import json
 import datetime
+from BreCal.validators.time_logic import validate_time_is_in_not_too_distant_future
+from BreCal.validators.validation_base_utils import check_if_string_has_special_characters
+from BreCal.database.enums import ParticipantType, ParticipantFlag
+
+# from BreCal. ... import check_if_user_is_bsmd_type
 
 def obj_dict(obj):
     if isinstance(obj, datetime.datetime):
@@ -49,10 +54,20 @@ class EvaluationType(IntEnum):
     def _missing_(cls, value):
         return cls.undefined
 
-class NotificationType(IntEnum):
+class NotificationType(IntEnum): 
+    """
+    Any user has the attributes
+        'notify_email' -> NotificationType.email
+        'notify_popup' -> NotificationType.push
+        'notify_whatsapp' -> undeclared
+        'notify_signal' -> undeclared
+    """
     undefined = 0
     email = 1
     push = 2
+    # whatsapp = 3
+    # signal = 4
+    
     @classmethod
     def _missing_(cls, value):
         return cls.undefined
@@ -104,7 +119,7 @@ class History:
         return self(id, participant_id, shipcall_id, timestamp, eta, ObjectType(type), OperationType(operation))
 
 class Error(Schema):
-    message = fields.String(required=True)
+    message = fields.String(metadata={'required':True})
 
 
 class GetVerifyInlineResp(Schema):
@@ -112,11 +127,17 @@ class GetVerifyInlineResp(Schema):
 
 @dataclass
 class Notification:
+    """
+    Base data class for any notification. 
+
+    Description:
+        'An entry corresponds to an alarm given by a violated rule during times update'
+    """
     id: int
-    shipcall_id: int
-    level: int
-    type: NotificationType
-    message: str
+    shipcall_id: int # 'shipcall record that caused the notification'
+    level: int # 'severity of the notification'
+    type: NotificationType # 'type of the notification'
+    message: str # 'individual message'
     created: datetime
     modified: datetime
 
@@ -142,68 +163,99 @@ class Participant(Schema):
     street: str
     postal_code: str
     city: str
-    type: int
+    type: int # fields.Enum(ParticipantType ...)
     flags: int
     created: datetime
     modified: datetime
     deleted: bool
 
+    @validates("type")
+    def validate_type(self, value):
+        # e.g., when an IntFlag has the values 1,2,4; the maximum valid value is 7
+        max_int = sum([int(val) for val in list(ParticipantType._value2member_map_.values())])
+        min_int = 0
+
+        valid_type = 0 <= value < max_int  
+        if not valid_type:
+            raise ValidationError(f"the provided integer is not supported for default behaviour of the ParticipantType IntFlag. Your choice: {value}. Supported values are: 0 <= value {max_int}")
+
+
+    @validates("flags")
+    def validate_flags(self, value):
+        # e.g., when an IntFlag has the values 1,2,4; the maximum valid value is 7
+        max_int = sum([int(val) for val in list(ParticipantFlag._value2member_map_.values())])
+        min_int = 0
+
+        valid_type = 0 <= value < max_int  
+        if not valid_type:
+            raise ValidationError(f"the provided integer is not supported for default behaviour of the ParticipantFlag IntFlag. Your choice: {value}. Supported values are: 0 <= value {max_int}")
+
+
 class ParticipantList(Participant):
     pass
 
 class ParticipantAssignmentSchema(Schema):
-    participant_id = fields.Int()
-    type = fields.Int()
+    participant_id = fields.Integer()
+    type = fields.Integer()
 
 class ShipcallSchema(Schema):
     def __init__(self):
         super().__init__(unknown=None)
         pass
 
-    id = fields.Int()
-    ship_id = fields.Int()
-    type = fields.Enum(ShipcallType,  required=True)
-    eta = fields.DateTime(Required = False, allow_none=True)
-    voyage = fields.Str(allow_none=True, metadata={'Required':False}) # Solving: RemovedInMarshmallow4Warning: Passing field metadata as keyword arguments is deprecated. Use the explicit `metadata=...` argument instead. Additional metadata: {'Required': False}
-    etd = fields.DateTime(Required = False, allow_none=True)
-    arrival_berth_id = fields.Int(Required = False, allow_none=True)
-    departure_berth_id = fields.Int(Required = False, allow_none=True)
-    tug_required = fields.Bool(Required = False, allow_none=True)
-    pilot_required = fields.Bool(Required = False, allow_none=True)
-    flags = fields.Int(Required = False, allow_none=True)
-    pier_side = fields.Bool(Required = False, allow_none=True)
-    bunkering = fields.Bool(Required = False, allow_none=True)
-    replenishing_terminal = fields.Bool(Required = False, allow_none=True)
-    replenishing_lock = fields.Bool(Required = False, allow_none=True)
-    draft = fields.Float(Required = False, allow_none=True)
-    tidal_window_from = fields.DateTime(Required = False, allow_none=True)
-    tidal_window_to = fields.DateTime(Required = False, allow_none=True)
-    rain_sensitive_cargo = fields.Bool(Required = False, allow_none=True)
-    recommended_tugs = fields.Int(Required = False, allow_none=True)
-    anchored = fields.Bool(Required = False, allow_none=True)
-    moored_lock = fields.Bool(Required = False, allow_none=True)
-    canceled = fields.Bool(Required = False, allow_none=True)
-    evaluation = fields.Enum(EvaluationType,  required=False, allow_none=True, default=EvaluationType.undefined)
+    id = fields.Integer(metadata={'required':True})
+    ship_id = fields.Integer(metadata={'required':True})
+    #type = fields.Enum(ShipcallType, default=ShipcallType.undefined) # type = fields.Integer() # make enum: shipcall type. add validator
+    type = fields.Integer(metadata={'required':True}) # make enum: shipcall type. add validator # type = fields.Enum(ShipcallType, default=ShipcallType.undefined) # type = fields.Integer() # make enum: shipcall type. add validator
+    eta = fields.DateTime(metadata={'required':False}, allow_none=True)
+    voyage = fields.String(allow_none=True, metadata={'Required':False}, validate=[validate.Length(max=16)]) # Solving: RemovedInMarshmallow4Warning: Passing field metadata as keyword arguments is deprecated. Use the explicit `metadata=...` argument instead. Additional metadata: {'Required': False}
+    etd = fields.DateTime(metadata={'required':False}, allow_none=True)
+    arrival_berth_id = fields.Integer(metadata={'required':False}, allow_none=True)
+    departure_berth_id = fields.Integer(metadata={'required':False}, allow_none=True)
+    tug_required = fields.Bool(metadata={'required':False}, allow_none=True)
+    pilot_required = fields.Bool(metadata={'required':False}, allow_none=True)
+    flags = fields.Integer(metadata={'required':False}, allow_none=True)
+    pier_side = fields.Bool(metadata={'required':False}, allow_none=True)
+    bunkering = fields.Bool(metadata={'required':False}, allow_none=True)
+    replenishing_terminal = fields.Bool(metadata={'required':False}, allow_none=True)
+    replenishing_lock = fields.Bool(metadata={'required':False}, allow_none=True)
+    draft = fields.Float(metadata={'required':False}, allow_none=True, validate=[validate.Range(min=0, max=20, min_inclusive=False, max_inclusive=True)])
+    tidal_window_from = fields.DateTime(metadata={'required':False}, allow_none=True)
+    tidal_window_to = fields.DateTime(metadata={'required':False}, allow_none=True)
+    rain_sensitive_cargo = fields.Bool(metadata={'required':False}, allow_none=True)
+    recommended_tugs = fields.Integer(metadata={'required':False}, allow_none=True, validate=[validate.Range(min=0, max=10, min_inclusive=True, max_inclusive=True)])
+    anchored = fields.Bool(metadata={'required':False}, allow_none=True)
+    moored_lock = fields.Bool(metadata={'required':False}, allow_none=True)
+    canceled = fields.Bool(metadata={'required':False}, allow_none=True)
+    evaluation = fields.Enum(EvaluationType,  metadata={'required':False}, allow_none=True, default=EvaluationType.undefined)
     evaluation_message = fields.Str(allow_none=True, metadata={'Required':False}) # Solving: RemovedInMarshmallow4Warning: Passing field metadata as keyword arguments is deprecated. Use the explicit `metadata=...` argument instead. Additional metadata: {'Required': False}
-    evaluation_time = fields.DateTime(Required = False, allow_none=True)
-    evaluation_notifications_sent = fields.Bool(Required = False, allow_none=True)
-    time_ref_point = fields.Int(Required = False, allow_none=True)
+    evaluation_time = fields.DateTime(metadata={'required':False}, allow_none=True)
+    evaluation_notifications_sent = fields.Bool(metadata={'required':False}, allow_none=True)
+    time_ref_point = fields.Integer(metadata={'required':False}, allow_none=True)
     participants = fields.List(fields.Nested(ParticipantAssignmentSchema))
-    created = fields.DateTime(Required = False, allow_none=True)
-    modified = fields.DateTime(Required = False, allow_none=True)
+    created = fields.DateTime(metadata={'required':False}, allow_none=True)
+    modified = fields.DateTime(metadata={'required':False}, allow_none=True)
 
     @post_load
     def make_shipcall(self, data, **kwargs):
         if 'type' in data:
-            data['type_value'] = data['type'].value
+            data['type_value'] = int(data['type'])
         else:
-            data['type_value'] = ShipcallType.undefined
+            data['type_value'] = int(ShipcallType.undefined)
         if 'evaluation' in data:
             if data['evaluation']:
-                data['evaluation_value'] = data['evaluation'].value           
+                data['evaluation_value'] = int(data['evaluation'])           
         else:
-            data['evaluation_value'] = EvaluationType.undefined
+            data['evaluation_value'] = int(EvaluationType.undefined)
         return data
+    
+    @validates("type")
+    def validate_type(self, value):
+        valid_shipcall_type = int(value) in [item.value for item in ShipcallType]
+        
+        if not valid_shipcall_type:
+            raise ValidationError(f"the provided type is not a valid shipcall type.")
+
 
 @dataclass
 class Participant_Assignment:
@@ -215,6 +267,9 @@ class Participant_Assignment:
     participant_id: int
     type: int # a variant would be to use the IntFlag type (with appropriate serialization)
 
+    def to_json(self):
+        return self.__dict__
+
 
 @dataclass
 class Shipcall:
@@ -230,7 +285,7 @@ class Shipcall:
     tug_required: bool
     pilot_required: bool
     flags: int
-    pier_side: bool
+    pier_side: bool # enumerator object in database/enum/PierSide
     bunkering: bool
     replenishing_terminal: bool
     replenishing_lock: bool
@@ -297,35 +352,91 @@ class ShipcallId(Schema):
 
 # this is the way!
 
+
 class TimesSchema(Schema):
     def __init__(self):
         super().__init__(unknown=None)
         pass
 
-    id = fields.Int(Required=False)
-    eta_berth = fields.DateTime(Required = False, allow_none=True)
-    eta_berth_fixed = fields.Bool(Required = False, allow_none=True)
-    etd_berth = fields.DateTime(Required = False, allow_none=True)
-    etd_berth_fixed = fields.Bool(Required = False, allow_none=True)
-    lock_time = fields.DateTime(Required = False, allow_none=True)
-    lock_time_fixed = fields.Bool(Required = False, allow_none=True)
-    zone_entry = fields.DateTime(Required = False, allow_none=True)
-    zone_entry_fixed = fields.Bool(Required = False, allow_none=True)
-    operations_start = fields.DateTime(Required = False, allow_none=True)
-    operations_end  = fields.DateTime(Required = False, allow_none=True)
-    remarks = fields.String(Required = False, allow_none=True)
-    participant_id = fields.Int(Required = True)
-    berth_id = fields.Int(Required = False, allow_none = True)
-    berth_info = fields.String(Required = False, allow_none=True)
-    pier_side = fields.Bool(Required = False, allow_none = True)
-    shipcall_id = fields.Int(Required = True)
-    participant_type = fields.Int(Required = False, allow_none=True)
-    ata = fields.DateTime(Required = False, allow_none=True)
-    atd = fields.DateTime(Required = False, allow_none=True)
-    eta_interval_end = fields.DateTime(Required = False, allow_none=True)
-    etd_interval_end = fields.DateTime(Required = False, allow_none=True)
-    created = fields.DateTime(Required = False, allow_none=True)
-    modified = fields.DateTime(Required = False, allow_none=True)
+    id = fields.Integer(metadata={'required':False})
+    eta_berth = fields.DateTime(metadata={'required':False}, allow_none=True)
+    eta_berth_fixed = fields.Bool(metadata={'required':False}, allow_none=True)
+    etd_berth = fields.DateTime(metadata={'required':False}, allow_none=True)
+    etd_berth_fixed = fields.Bool(metadata={'required':False}, allow_none=True)
+    lock_time = fields.DateTime(metadata={'required':False}, allow_none=True)
+    lock_time_fixed = fields.Bool(metadata={'required':False}, allow_none=True)
+    zone_entry = fields.DateTime(metadata={'required':False}, allow_none=True)
+    zone_entry_fixed = fields.Bool(metadata={'required':False}, allow_none=True)
+    operations_start = fields.DateTime(metadata={'required':False}, allow_none=True)
+    operations_end  = fields.DateTime(metadata={'required':False}, allow_none=True)
+    remarks = fields.String(metadata={'required':False}, allow_none=True, validate=[validate.Length(max=512)])
+    participant_id = fields.Integer(metadata={'required':True})
+    berth_id = fields.Integer(metadata={'required':False}, allow_none = True)
+    berth_info = fields.String(metadata={'required':False}, allow_none=True, validate=[validate.Length(max=512)])
+    pier_side = fields.Bool(metadata={'required':False}, allow_none = True)
+    shipcall_id = fields.Integer(metadata={'required':True})
+    participant_type = fields.Integer(Required = False, allow_none=True)# TODO: could become Enum. fields.Enum(ParticipantType, metadata={'required':False}, allow_none=True, default=ParticipantType.undefined) #fields.Integer(metadata={'required':False}, allow_none=True)
+    ata = fields.DateTime(metadata={'required':False}, allow_none=True)
+    atd = fields.DateTime(metadata={'required':False}, allow_none=True)
+    eta_interval_end = fields.DateTime(metadata={'required':False}, allow_none=True)
+    etd_interval_end = fields.DateTime(metadata={'required':False}, allow_none=True)
+    created = fields.DateTime(metadata={'required':False}, allow_none=True)
+    modified = fields.DateTime(metadata={'required':False}, allow_none=True)
+
+    @validates("participant_type")
+    def validate_participant_type(self, value):
+        # #TODO: it may also make sense to block multi-assignments, whereas a value could be BSMD+AGENCY
+        # while the validation fails when one of those multi-assignments is BSMD, it passes in cases,
+        # such as AGENCY+PILOT
+
+        # a participant type should not be .BSMD
+        if not isinstance(value, ParticipantType):
+            value = ParticipantType(value)
+
+        if ParticipantType.BSMD in value:
+            raise ValidationError(f"the participant_type must not be .BSMD")
+
+    @validates("eta_berth")
+    def validate_eta_berth(self, value):
+        # violation when time is not in the future, but also does not exceed a threshold for the 'reasonable' future
+        # when 'value' is 'None', a ValidationError is not issued.
+        valid_time = validate_time_is_in_not_too_distant_future(raise_validation_error=True, value=value, months=12)
+        return
+
+    @validates("etd_berth")
+    def validate_etd_berth(self, value):
+        # violation when time is not in the future, but also does not exceed a threshold for the 'reasonable' future
+        # when 'value' is 'None', a ValidationError is not issued.
+        valid_time = validate_time_is_in_not_too_distant_future(raise_validation_error=True, value=value, months=12)
+        return
+
+    @validates("lock_time")
+    def validate_lock_time(self, value):
+        # violation when time is not in the future, but also does not exceed a threshold for the 'reasonable' future
+        # when 'value' is 'None', a ValidationError is not issued.
+        valid_time = validate_time_is_in_not_too_distant_future(raise_validation_error=True, value=value, months=12)
+        return
+
+    @validates("zone_entry")
+    def validate_zone_entry(self, value):
+        # violation when time is not in the future, but also does not exceed a threshold for the 'reasonable' future
+        # when 'value' is 'None', a ValidationError is not issued.
+        valid_time = validate_time_is_in_not_too_distant_future(raise_validation_error=True, value=value, months=12)
+        return
+
+    @validates("operations_start")
+    def validate_operations_start(self, value):
+        # violation when time is not in the future, but also does not exceed a threshold for the 'reasonable' future
+        # when 'value' is 'None', a ValidationError is not issued.
+        valid_time = validate_time_is_in_not_too_distant_future(raise_validation_error=True, value=value, months=12)
+        return
+
+    @validates("operations_end")
+    def validate_operations_end(self, value):
+        # violation when time is not in the future, but also does not exceed a threshold for the 'reasonable' future
+        # when 'value' is 'None', a ValidationError is not issued.
+        valid_time = validate_time_is_in_not_too_distant_future(raise_validation_error=True, value=value, months=12)
+        return
 
 # deserialize PUT object target
 
@@ -333,13 +444,26 @@ class UserSchema(Schema):
     def __init__(self):
         super().__init__(unknown=None)
         pass
-    id = fields.Int(required=True)
-    first_name = fields.Str(allow_none=True, metadata={'Required':False})
-    last_name = fields.Str(allow_none=True, metadata={'Required':False})
-    user_phone = fields.Str(allow_none=True, metadata={'Required':False})
-    user_email = fields.Str(allow_none=True, metadata={'Required':False})
-    old_password = fields.Str(allow_none=True, metadata={'Required':False})
-    new_password = fields.Str(allow_none=True, metadata={'Required':False})
+    id = fields.Integer(metadata={'required':True})
+    first_name = fields.String(allow_none=True, metadata={'Required':False}, validate=[validate.Length(max=64)])
+    last_name = fields.String(allow_none=True, metadata={'Required':False}, validate=[validate.Length(max=64)])
+    user_phone = fields.String(allow_none=True, metadata={'Required':False})
+    user_email = fields.String(allow_none=True, metadata={'Required':False}, validate=[validate.Length(max=64)])
+    old_password = fields.String(allow_none=True, metadata={'Required':False}, validate=[validate.Length(max=128)])
+    new_password = fields.String(allow_none=True, metadata={'Required':False}, validate=[validate.Length(min=6, max=128)])
+    # #TODO: the user schema does not (yet) include the 'notify_' fields
+
+    @validates("user_phone")
+    def validate_user_phone(self, value):
+        valid_characters = list(map(str,range(0,10)))+["+", " "]
+        if not all([v in valid_characters for v in value]):
+            raise ValidationError(f"one of the phone number values is not valid.")
+        
+    @validates("user_email")
+    def validate_user_email(self, value):
+        if not "@" in value:
+            raise ValidationError(f"invalid email address")
+    
 
 @dataclass
 class Times:
@@ -380,10 +504,10 @@ class User:
     user_phone: str
     password_hash: str
     api_key: str
-    notify_email: bool
-    notify_whatsapp: bool
-    notify_signal: bool
-    notify_popup: bool
+    notify_email: bool # #TODO_clarify: should we use an IntFlag for multi-assignment?
+    notify_whatsapp: bool # #TODO_clarify: should we use an IntFlag for multi-assignment?
+    notify_signal: bool # #TODO_clarify: should we use an IntFlag for multi-assignment?
+    notify_popup: bool # #TODO_clarify: should we use an IntFlag for multi-assignment?
     created: datetime
     modified: datetime
 
@@ -409,13 +533,13 @@ class ShipSchema(Schema):
         super().__init__(unknown=None)
         pass
 
-    id = fields.Int(Required=False)
+    id = fields.Int(metadata={'required':False})
     name = fields.String(allow_none=False, metadata={'Required':True})
     imo = fields.Int(allow_none=False, metadata={'Required':True})
     callsign = fields.String(allow_none=True, metadata={'Required':False})
     participant_id = fields.Int(allow_none=True, metadata={'Required':False})
-    length = fields.Float(allow_none=True, metadata={'Required':False})
-    width = fields.Float(allow_none=True, metadata={'Required':False})
+    length = fields.Float(allow_none=True, metadata={'Required':False}, validate=[validate.Range(min=0, max=1000, min_inclusive=False, max_inclusive=False)])
+    width = fields.Float(allow_none=True, metadata={'Required':False}, validate=[validate.Range(min=0, max=100, min_inclusive=False, max_inclusive=False)])
     is_tug = fields.Bool(allow_none=True, metadata={'Required':False}, default=False)
     bollard_pull = fields.Int(allow_none=True, metadata={'Required':False})
     eni = fields.Int(allow_none=True, metadata={'Required':False})
@@ -423,6 +547,34 @@ class ShipSchema(Schema):
     modified = fields.DateTime(allow_none=True, metadata={'Required':False})
     deleted = fields.Bool(allow_none=True, metadata={'Required':False}, default=False)
 
+    @validates("name")
+    def validate_name(self, value):
+        character_length = len(str(value))
+        if character_length>=64:
+            raise ValidationError(f"'name' argument should have at max. 63 characters")
+        
+        if check_if_string_has_special_characters(value):
+            raise ValidationError(f"'name' argument should not have special characters.")
+        return
+
+    @validates("imo")
+    def validate_imo(self, value):
+        imo_length = len(str(value))
+        if imo_length != 7:
+            raise ValidationError(f"'imo' should be a 7-digit number")
+        return
+
+    @validates("callsign")
+    def validate_callsign(self, value):
+        if value is not None:
+            callsign_length = len(str(value))
+            if callsign_length>8:
+                raise ValidationError(f"'callsign' argument should not have more than 8 characters")
+            
+            if check_if_string_has_special_characters(value):
+                raise ValidationError(f"'callsign' argument should not have special characters.")
+        return
+
 
 class TimesId(Schema):
     pass
@@ -442,3 +594,22 @@ class Shipcalls(Shipcall):
 
 class TimesList(Times):
     pass
+
+@dataclass
+class ShipcallParticipantMap:
+    id: int
+    shipcall_id: int
+    participant_id: int
+    type : ShipcallType
+    created: datetime
+    modified: datetime
+
+    def to_json(self):
+        return {
+            "id": self.id,
+            "shipcall_id": self.shipcall_id,
+            "participant_id": self.participant_id,
+            "type": self.type.name,
+            "created": self.created.isoformat() if self.created else "",
+            "modified": self.modified.isoformat() if self.modified else "",
+        }
diff --git a/src/server/BreCal/services/auth_guard.py b/src/server/BreCal/services/auth_guard.py
index 9c5824d..9bd27c6 100644
--- a/src/server/BreCal/services/auth_guard.py
+++ b/src/server/BreCal/services/auth_guard.py
@@ -9,6 +9,7 @@ def check_jwt():
     if not token:
         raise Exception('Missing access token')
     jwt = token.split('Bearer ')[1]
+
     try:
         return decode_jwt(jwt)
     except Exception as e:
diff --git a/src/server/BreCal/services/email_handling.py b/src/server/BreCal/services/email_handling.py
new file mode 100644
index 0000000..e06021d
--- /dev/null
+++ b/src/server/BreCal/services/email_handling.py
@@ -0,0 +1,174 @@
+import os
+import typing
+import smtplib
+from getpass import getpass
+from email.message import EmailMessage
+import mimetypes
+
+import email
+# from email.mime.base import MIMEBase
+# from email.mime.image import MIMEImage
+# from email.mime.text import MIMEText
+from email.mime.multipart import MIMEMultipart
+from email.mime.application import MIMEApplication
+
+
+class EmailHandler():
+    """
+    Creates an EmailHandler, which is capable of connecting to a mail server at a respective port, 
+    as well as logging into a specific user's mail address. 
+    Upon creating messages, these can be sent via this handler. 
+
+    Options:
+        mail_server: address of the server, such as 'smtp.gmail.com' or 'w01d5503.kasserver.com
+        mail_port: 
+            25 - SMTP Port, to send emails
+            110 - POP3 Port, to receive emails
+            143 - IMAP Port, to receive from IMAP
+            465 - SSL Port of SMTP
+            587 - alternative SMTP Port
+            993 - SSL/TLS-Port of IMAP
+            995 - SSL/TLS-Port of POP3
+        mail_address: a specific user's Email address, which will be used to send Emails. Example: "my_user@gmail.com"
+    """
+    def __init__(self, mail_server:str, mail_port:int, mail_address:str):
+        self.mail_server = mail_server
+        self.mail_port = mail_port
+        self.mail_address = mail_address
+
+        self.server = smtplib.SMTP_SSL(self.mail_server, self.mail_port) # alternatively, SMTP
+
+    def check_state(self):
+        """check, whether the server login took place and is open."""
+        try:
+            (status_code, status_msg) = self.server.noop()
+            return status_code==250 # 250: b'2.0.0 Ok'
+        except smtplib.SMTPServerDisconnected:
+            return False
+        
+    def check_connection(self):
+        """check, whether the server object is connected to the server. If not, connect it. """
+        try:
+            self.server.ehlo()
+        except smtplib.SMTPServerDisconnected:
+            self.server.connect(self.mail_server, self.mail_port)
+        return
+    
+    def check_login(self)->bool:
+        """check, whether the server object is logged in as a user"""
+        user = self.server.__dict__.get("user",None)
+        return user is not None
+
+    def login(self, interactive:bool=True):
+        """
+        login on the determined mail server's mail address. By default, this function opens an interactive window to 
+        type the password without echoing (printing '*******' instead of readable characters). 
+
+        returns (status_code, status_msg)
+        """
+        self.check_connection()
+        if interactive:
+            (status_code, status_msg) = self.server.login(self.mail_address, password=getpass())
+        else:
+            # fernet + password file
+            raise NotImplementedError()
+        return (status_code, status_msg) # should be: (235, b'2.7.0 Authentication successful')
+
+    def create_email(self, subject:str, message_body:str)->EmailMessage:
+        """
+        Create an EmailMessage object, which contains the Email's header ("Subject"), content ("Message Body") and the sender's address ("From").
+        The EmailMessage object does not contain the recipients yet, as these will be defined upon sending the Email. 
+        """
+        msg = EmailMessage()
+        msg["Subject"] = subject
+        msg["From"] = self.mail_address
+        #msg["To"] = email_tgts # will be defined in self.send_email
+        msg.set_content(message_body)
+        return msg
+        
+    def build_recipients(self, email_tgts:list[str]):
+        """
+        email formatting does not support lists. Instead, items are joined into a comma-space-separated string. 
+        Example: 
+            [mail1@mail.com, mail2@mail.com] becomes 
+            'mail1@mail.com, mail2@mail.com'
+        """
+        return ', '.join(email_tgts)
+    
+    def open_mime_application(self, path:str)->MIMEApplication:
+        """open a local file, read the bytes into a MIMEApplication object, which is built with the proper subtype (based on the file extension)"""
+        with open(path, 'rb') as file:
+            attachment = MIMEApplication(file.read(), _subtype=mimetypes.MimeTypes().guess_type(path))
+
+        attachment.add_header('Content-Disposition','attachment',filename=str(os.path.basename(path)))
+        return attachment
+    
+    def attach_file(self, path:str, msg:email.mime.multipart.MIMEMultipart)->None:
+        """
+        attach a file to the message. This function opens the file, reads its bytes, defines the mime type by the 
+        path extension. The filename is appended as the header. 
+
+        mimetypes:  # https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/MIME_types/Common_types
+        """
+        attachment = self.open_mime_application(path)
+        msg.attach(attachment)
+        return
+    
+    def send_email(self, msg:EmailMessage, email_tgts:list[str], cc_tgts:typing.Optional[list[str]]=None, bcc_tgts:typing.Optional[list[str]]=None, debug:bool=False)->typing.Union[dict,EmailMessage]:
+        """
+        send a prepared email message to recipients (email_tgts), copy (cc_tgts) and blind copy (bcc_tgts). 
+        Returns a dictionary of feedback, which is commonly empty and the EmailMessage. 
+        
+        When failing, this function returns an SMTP error instead of returning the default outputs. 
+        """
+        # Set the Recipients
+        msg["To"] = self.build_recipients(email_tgts)
+
+        # optionally, add CC and BCC (copy and blind-copy)
+        if cc_tgts is not None:
+            msg["Cc"] = self.build_recipients(cc_tgts)
+        if bcc_tgts is not None:
+            msg["Bcc"] = self.build_recipients(bcc_tgts)
+
+        # when debugging, do not send the Email, but return the EmailMessage. 
+        if debug:
+            return {}, msg
+        
+        assert self.check_login(), f"currently not logged in. Cannot send an Email. Make sure to properly use self.login first. "
+        # send the prepared EmailMessage via the server.
+        feedback = self.server.send_message(msg)
+        return feedback, msg
+    
+    def translate_mail_to_multipart(self, msg:EmailMessage):
+        """EmailMessage does not support HTML and attachments. Hence, one can convert an EmailMessage object."""
+        if msg.is_multipart():
+            return msg
+
+        # create a novel MIMEMultipart email
+        msg_new = MIMEMultipart("mixed")
+        headers = list((k, v) for (k, v) in msg.items() if k not in ("Content-Type", "Content-Transfer-Encoding"))
+
+        # add the headers of msg to the new message
+        for k,v in headers:
+            msg_new[k] = v
+
+        # delete the headers from msg
+        for k,v in headers:
+            del msg[k]
+
+        # attach the remainder of the msg, such as the body, to the MIMEMultipart
+        msg_new.attach(msg)
+        return msg_new
+    
+    def print_email_attachments(self, msg:MIMEMultipart)->list[str]:
+        """return a list of lines of an Email, which contain 'filename=' as a list. """
+        return [line_ for line_ in msg.as_string().split("\n") if "filename=" in line_]
+    
+    def close(self):
+        self.server.__dict__.pop("user",None)
+        self.server.__dict__.pop("password",None)
+
+        # quit the server connection (internally uses .close)
+        self.server.quit()
+        return
+
diff --git a/src/server/BreCal/services/jwt_handler.py b/src/server/BreCal/services/jwt_handler.py
index 66c0f43..d1e7ad6 100644
--- a/src/server/BreCal/services/jwt_handler.py
+++ b/src/server/BreCal/services/jwt_handler.py
@@ -7,11 +7,41 @@ def create_api_key():
     return secrets.token_urlsafe(16)
 
 def generate_jwt(payload, lifetime=None):
+    """
+    creates an encoded token, which is based on the 'SECRET_KEY' environment variable. The environment variable
+    is set when the .wsgi application is started or can theoretically be set on system-level.
+
+    args:
+        payload:
+            json-dictionary with key:value pairs. 
+
+        lifetime:
+            When a 'lifetime' (integer) is provided, the payload will be extended by an expiration key 'exp', which is
+            valid for the next {lifetime} minutes. 
+
+    returns: token, a JWT-encoded string
+    """
     if lifetime:
         payload['exp'] = (datetime.datetime.now() + datetime.timedelta(minutes=lifetime)).timestamp()
     return jwt.encode(payload, os.environ.get('SECRET_KEY'), algorithm="HS256")
 
 def decode_jwt(token):
+    """
+    this function reverts the {generate_jwt} function. An encoded JWT token is decoded into a JSON dictionary.
+    The function is commonly used to decode a login-token and obtain a 'user_data' variable, which is a dictionary.
+
+    Example of 'user_data':
+        {
+            'id': 1,
+            'participant_id': 1,
+            'first_name': 'Firstname',
+            'last_name': 'Lastname',
+            'user_name': 'xUsername01',
+            'user_phone': '+01 123 456 7890',
+            'user_email': 'firstname.lastname@internet.com',
+            'exp': 1716881626.056438 # expiration timestamp
+        }
+    """
     return jwt.decode(token, os.environ.get('SECRET_KEY'), algorithms=["HS256"])
 
 
diff --git a/src/server/BreCal/services/schedule_routines.py b/src/server/BreCal/services/schedule_routines.py
index 542b213..a36a1fc 100644
--- a/src/server/BreCal/services/schedule_routines.py
+++ b/src/server/BreCal/services/schedule_routines.py
@@ -3,6 +3,7 @@ import pydapper
 from BreCal.schemas import model
 from BreCal.local_db import getPoolConnection
 from BreCal.database.update_database import evaluate_shipcall_state
+from BreCal.database.sql_queries import create_sql_query_shipcall_get
 
 import threading
 import schedule
@@ -26,16 +27,8 @@ def UpdateShipcalls(options:dict = {'past_days':2}):
         pooledConnection = getPoolConnection()
         commands = pydapper.using(pooledConnection)
 
-        query = ("SELECT s.id as id, ship_id, type, eta, voyage, etd, arrival_berth_id, departure_berth_id, tug_required, pilot_required, "
-                "flags, s.pier_side, bunkering, replenishing_terminal, replenishing_lock, draft, tidal_window_from, tidal_window_to, rain_sensitive_cargo, recommended_tugs, "
-                "anchored, moored_lock, canceled, evaluation, evaluation_message, evaluation_notifications_sent, evaluation_time, s.created as created, s.modified as modified, time_ref_point FROM shipcall s " +
-                "LEFT JOIN times t ON t.shipcall_id = s.id AND t.participant_type = 8 "
-                "WHERE "
-                "(type = 1 AND (COALESCE(t.eta_berth, eta) >= DATE(NOW() - INTERVAL %d DAY))) OR "
-                "((type = 2 OR type = 3) AND (COALESCE(t.etd_berth, etd) >= DATE(NOW() - INTERVAL %d DAY)))"
-                "ORDER BY s.id") % (options["past_days"], options["past_days"])
-
-        # obtain data from the MYSQL database
+        # obtain data from the MYSQL database (uses 'options' to filter the resulting data by the ETA, considering those entries of 'past_days'-range)
+        query = create_sql_query_shipcall_get(options)
         data = commands.query(query, model=model.Shipcall)
 
         # get the shipcall ids, which are of interest
@@ -57,6 +50,11 @@ def add_function_to_schedule__update_shipcalls(interval_in_minutes:int, options:
     schedule.every(interval_in_minutes).minutes.do(UpdateShipcalls, **kwargs_)
     return
 
+def add_function_to_schedule__send_notifications(vr, interval_in_minutes:int=10):
+    schedule.every(interval_in_minutes).minutes.do(vr.notifier.send_notifications)
+    return
+
+
 def setup_schedule(update_shipcalls_interval_in_minutes:int=60):
 
     logging.getLogger('schedule').setLevel(logging.INFO); # set the logging level of the schedule module to INFO
diff --git a/src/server/BreCal/stubs/notification.py b/src/server/BreCal/stubs/notification.py
index 63df90f..8971a76 100644
--- a/src/server/BreCal/stubs/notification.py
+++ b/src/server/BreCal/stubs/notification.py
@@ -7,7 +7,6 @@ def get_notification_simple():
     """creates a default notification, where 'created' is now, and modified is now+10 seconds"""
     notification_id = generate_uuid1_int() # uid?
     times_id = generate_uuid1_int() # uid?
-    acknowledged = False
     level = 10
     type = 0
     message = "hello world"
@@ -17,7 +16,6 @@ def get_notification_simple():
     notification = Notification(
         notification_id,
         times_id,
-        acknowledged,
         level,
         type,
         message,
diff --git a/src/server/BreCal/stubs/participant.py b/src/server/BreCal/stubs/participant.py
index 38f303c..1a4aef3 100644
--- a/src/server/BreCal/stubs/participant.py
+++ b/src/server/BreCal/stubs/participant.py
@@ -30,3 +30,8 @@ def get_participant_simple():
         deleted
     )
     return participant
+
+
+def get_stub_list_of_valid_participants():
+    participants = [{'participant_id': 2, 'type': 4}, {'participant_id': 3, 'type': 1}, {'participant_id': 4, 'type': 2}, {'participant_id': 5, 'type': 8}]
+    return participants
diff --git a/src/server/BreCal/stubs/ship.py b/src/server/BreCal/stubs/ship.py
index 4ab288e..77e6e45 100644
--- a/src/server/BreCal/stubs/ship.py
+++ b/src/server/BreCal/stubs/ship.py
@@ -36,3 +36,27 @@ def get_ship_simple():
     )
     return ship
 
+def get_stub_valid_ship():
+    post_data = {
+        'name': 'BOTHNIABORG',
+        'imo': 9267728,
+        'callsign': "PBIO",
+        'participant_id': None,
+        'length': 153.05,
+        'width': 21.8,
+        'is_tug': 0,
+        'bollard_pull': None,
+        'eni': None,
+        'created': '2023-10-04 11:52:32',
+        'modified': None,
+        'deleted': 0
+    }
+    return post_data
+
+def get_stub_valid_ship_loaded_model(post_data=None):
+    from BreCal.schemas import model
+    if post_data is None:
+        post_data = get_stub_valid_ship()
+    loadedModel = model.ShipSchema().load(data=post_data, many=False, partial=True)
+    return loadedModel
+ 
\ No newline at end of file
diff --git a/src/server/BreCal/stubs/shipcall.py b/src/server/BreCal/stubs/shipcall.py
index e86d379..299fdbe 100644
--- a/src/server/BreCal/stubs/shipcall.py
+++ b/src/server/BreCal/stubs/shipcall.py
@@ -3,25 +3,30 @@ from BreCal.stubs import generate_uuid1_int
 from BreCal.schemas.model import Shipcall
 from dataclasses import field
 
+import json
+import datetime
+from BreCal.schemas.model import ShipcallType
+from BreCal.stubs.participant import get_stub_list_of_valid_participants
+
 def get_shipcall_simple():
     # only used for the stub
     base_time = datetime.datetime.now()
 
-    shipcall_id = generate_uuid1_int()
-    ship_id = generate_uuid1_int()
+    shipcall_id = 124 # generate_uuid1_int()
+    ship_id = 5 # generate_uuid1_int()
 
     eta = base_time+datetime.timedelta(hours=3, minutes=12)
     role_type = 1
     voyage = "987654321"
     etd = base_time+datetime.timedelta(hours=6, minutes=12) # should never be before eta
 
-    arrival_berth_id = generate_uuid1_int()
-    departure_berth_id = generate_uuid1_int()
+    arrival_berth_id = 140 #generate_uuid1_int()
+    departure_berth_id = 140 #generate_uuid1_int()
 
     tug_required = False
     pilot_required = False
 
-    flags = 0 # #TODO_shipcall_flags. What is meant here? What should be tested?
+    flags = 0 # #TODO_shipcall_flags. What is meant here? What should be tested? 
     pier_side = False # whether a ship will be fixated on the pier side. en: pier side, de: Anlegestelle. From 'BremenCalling_Datenmodell.xlsx': gedreht/ungedreht
     bunkering = False # #TODO_bunkering_unclear
     replenishing_terminal = False # en: replenishing terminal, de: Nachfüll-Liegeplatz
@@ -37,11 +42,13 @@ def get_shipcall_simple():
     recommended_tugs = 2 # assert 0<recommended_tugs<={threshold}. E.g., 20 should not be exceeded.
     anchored = False
     moored_lock = False # de: 'Festmacherschleuse', en: 'moored lock'
-
     canceled = False
+    
+    time_ref_point = 0
+
     evaluation = None
     evaluation_message = ""
-    evaluation_time = None
+    evaluation_time = datetime.datetime.now()
     evaluation_notifications_sent = False
     created = datetime.datetime.now()
     modified = created+datetime.timedelta(seconds=10)
@@ -76,10 +83,125 @@ def get_shipcall_simple():
         evaluation_message,
         evaluation_time,
         evaluation_notifications_sent,
+        time_ref_point,
         created,
         modified,
         participants,
     )
     return shipcall
 
+def create_postman_stub_shipcall():
+    """
+    this function returns the common stub, which is used to POST data to shipcalls via POSTMAN. However,
+    the stub-function is updated with a dynamic ETA in the future, so the POST-request does not fail. 
 
+    Also provides a stub arrival_berth_id, so the POST-request succeeds.
+    """
+    shipcall = {
+        'ship_id': 1,
+        'type': 1,
+        'eta': (datetime.datetime.now()+datetime.timedelta(hours=3)).isoformat(),
+        'voyage': '43B',
+        'arrival_berth_id':142,
+        'tug_required': False,
+        'pilot_required': True,
+        'flags': 0,
+        'pier_side': False,
+        'bunkering': True,
+        'recommended_tugs': 2
+    }
+    return shipcall
+
+
+def get_stub_valid_shipcall_base():
+    tidal_window_from = (datetime.datetime.now()+datetime.timedelta(minutes=15)).isoformat()
+    tidal_window_to = (datetime.datetime.now()+datetime.timedelta(minutes=115)).isoformat()
+
+    shipcall_base = {
+        'ship_id': 1,
+        'voyage': '43B',
+        'tug_required': False,
+        'pilot_required': True,
+        'flags': 0,
+        'pier_side': False,
+        'bunkering': True,
+        'recommended_tugs': 2,
+        'tidal_window_from' : tidal_window_from,
+        'tidal_window_to' : tidal_window_to
+    }
+    return shipcall_base
+
+def get_stub_valid_shipcall_arrival():
+    eta = (datetime.datetime.now()+datetime.timedelta(minutes=45)).isoformat()
+
+    post_data = {
+        **get_stub_valid_shipcall_base(),
+        **{
+            'type': int(ShipcallType.arrival),
+            'eta': eta,
+            'participants':get_stub_list_of_valid_participants(),
+            'arrival_berth_id':139,
+        }
+    }
+    return post_data
+
+def get_stub_valid_shipcall_departure():
+    etd = (datetime.datetime.now()+datetime.timedelta(minutes=45)).isoformat()
+
+    post_data = {
+        **get_stub_valid_shipcall_base(),
+        **{
+            'type': int(ShipcallType.departure),
+            'etd': etd,
+            'participants':get_stub_list_of_valid_participants(),
+            'departure_berth_id':139,
+        }
+    }
+    return post_data
+
+def get_stub_valid_shipcall_shifting():
+    eta = (datetime.datetime.now()+datetime.timedelta(minutes=45)).isoformat()
+    etd = (datetime.datetime.now()+datetime.timedelta(minutes=60)).isoformat()
+
+    post_data = {
+        **get_stub_valid_shipcall_base(),
+        **{
+            'type': int(ShipcallType.shifting),
+            'eta': eta,
+            'etd': etd,
+            'participants':get_stub_list_of_valid_participants(),
+            'arrival_berth_id':139,
+            'departure_berth_id':139,
+        }
+    }
+    return post_data
+
+def get_stub_shipcall_arrival_invalid_missing_eta():
+    post_data = get_stub_valid_shipcall_arrival()
+    post_data.pop("eta", None)
+    return post_data
+
+def get_stub_shipcall_departure_invalid_missing_etd():
+    post_data = get_stub_valid_shipcall_departure()
+    post_data.pop("etd", None)
+    return post_data
+
+def get_stub_shipcall_shifting_invalid_missing_eta():
+    post_data = get_stub_valid_shipcall_shifting()
+    post_data.pop("eta", None)
+    return post_data
+
+def get_stub_shipcall_shifting_invalid_missing_etd():
+    post_data = get_stub_valid_shipcall_shifting()
+    post_data.pop("etd", None)
+    return post_data
+
+def get_stub_shipcall_arrival_invalid_missing_type():
+    post_data = get_stub_valid_shipcall_arrival()
+    post_data.pop("type", None)
+    return post_data
+
+def get_stub_valid_ship_loaded_model(post_data):
+    from BreCal.schemas import model
+    loadedModel = model.ShipcallSchema().load(data=post_data, many=False, partial=True)
+    return loadedModel
diff --git a/src/server/BreCal/stubs/times_full.py b/src/server/BreCal/stubs/times_full.py
index f0176a1..b88fdb1 100644
--- a/src/server/BreCal/stubs/times_full.py
+++ b/src/server/BreCal/stubs/times_full.py
@@ -5,10 +5,12 @@ users will thereby be able to modify these values
 import datetime
 
 from BreCal.stubs import generate_uuid1_int
-from BreCal.schemas.model import Times
+from BreCal.schemas.model import Times, ParticipantType
+from BreCal.database.sql_utils import get_user_data_for_id
 
 
-def get_times_full_simple():
+
+def get_times_full_simple(return_dataclass=True):
     # only used for the stub
     base_time = datetime.datetime.now()
 
@@ -27,6 +29,11 @@ def get_times_full_simple():
 
     zone_entry = etd_berth+datetime.timedelta(hours=0, minutes=15)
     zone_entry_fixed = False
+    
+    ata = eta_berth+datetime.timedelta(hours=0, minutes=15)
+    atd = etd_berth+datetime.timedelta(hours=0, minutes=15)
+    eta_interval_end =  eta_berth + datetime.timedelta(hours=0, minutes=25)
+    etd_interval_end  = etd_berth + datetime.timedelta(hours=0, minutes=25)
 
     operations_start = zone_entry+datetime.timedelta(hours=1, minutes=30)
     operations_end = operations_start+datetime.timedelta(hours=4, minutes=30)
@@ -44,28 +51,86 @@ def get_times_full_simple():
     created = datetime.datetime.now()
     modified = created+datetime.timedelta(seconds=10)
 
-    times = Times(
-        id=times_id, 
-        eta_berth=eta_berth, 
-        eta_berth_fixed=eta_berth_fixed, 
-        etd_berth=etd_berth, 
-        etd_berth_fixed=etd_berth_fixed,
-        lock_time=lock_time,
-        lock_time_fixed=lock_time_fixed,
-        zone_entry=zone_entry,
-        zone_entry_fixed=zone_entry_fixed,
-        operations_start=operations_start,
-        operations_end=operations_end,
-        remarks=remarks, 
-        participant_id=participant_id,
-        berth_id=berth_id,
-        berth_info=berth_info,
-        pier_side=pier_side,
-        participant_type=participant_type,
-        shipcall_id=shipcall_id,
-        created=created,
-        modified=modified,
-    )   
+    if return_dataclass:
+        times = Times(
+            id=times_id, 
+            eta_berth=eta_berth, 
+            eta_berth_fixed=eta_berth_fixed, 
+            etd_berth=etd_berth, 
+            etd_berth_fixed=etd_berth_fixed,
+            lock_time=lock_time,
+            lock_time_fixed=lock_time_fixed,
+            zone_entry=zone_entry,
+            zone_entry_fixed=zone_entry_fixed,
+            operations_start=operations_start,
+            operations_end=operations_end,
+            remarks=remarks, 
+            participant_id=participant_id,
+            berth_id=berth_id,
+            berth_info=berth_info,
+            pier_side=pier_side,
+            participant_type=participant_type,
+            shipcall_id=shipcall_id,
+            ata=ata,
+            atd=atd,
+            eta_interval_end=eta_interval_end,
+            etd_interval_end=etd_interval_end,
+            created=created,
+            modified=modified,
+        )   
+    else:
+        times = dict(
+            id=times_id, 
+            eta_berth=eta_berth, 
+            eta_berth_fixed=eta_berth_fixed, 
+            etd_berth=etd_berth, 
+            etd_berth_fixed=etd_berth_fixed,
+            lock_time=lock_time,
+            lock_time_fixed=lock_time_fixed,
+            zone_entry=zone_entry,
+            zone_entry_fixed=zone_entry_fixed,
+            operations_start=operations_start,
+            operations_end=operations_end,
+            remarks=remarks, 
+            participant_id=participant_id,
+            berth_id=berth_id,
+            berth_info=berth_info,
+            pier_side=pier_side,
+            participant_type=participant_type,
+            shipcall_id=shipcall_id,
+            ata=ata,
+            atd=atd,
+            eta_interval_end=eta_interval_end,
+            etd_interval_end=etd_interval_end,
+            created=created,
+            modified=modified,)
+        times = {k:v.isoformat() if isinstance(v, datetime.datetime) else v for k,v in times.items()}
     return times
 
+def get_valid_stub_times():
+    """create a stub entry for a times dataset, which is valid"""
+    times_entry = get_times_full_simple(return_dataclass=False)
 
+    times_entry.pop('id',None)
+    times_entry["participant_id"] = 136
+    times_entry["participant_type"] = int(ParticipantType.PILOT)
+    times_entry["shipcall_id"] = 222
+    times_entry["berth_id"] = 143
+    times_entry["remarks"] = "stub entry."
+    return times_entry
+
+
+def get_valid_stub_times_loaded_model(post_data=None):
+    from BreCal.schemas import model
+    if post_data is None:
+        post_data = get_valid_stub_times()
+    loadedModel = model.TimesSchema().load(data=post_data, many=False, partial=True)
+    return loadedModel
+
+def get_valid_stub_for_pytests(user_id:int=3): 
+    user_data = get_user_data_for_id(user_id=user_id)
+    post_data = get_valid_stub_times()
+
+    content = post_data
+    loadedModel = get_valid_stub_times_loaded_model(post_data=post_data)
+    return user_data, loadedModel, content
diff --git a/src/server/BreCal/stubs/user.py b/src/server/BreCal/stubs/user.py
index e469c55..908f512 100644
--- a/src/server/BreCal/stubs/user.py
+++ b/src/server/BreCal/stubs/user.py
@@ -18,6 +18,11 @@ def get_user_simple():
 
     created = datetime.datetime.now()
     modified = created+datetime.timedelta(seconds=10)
+    
+    notify_email = True
+    notify_whatsapp = True
+    notify_signal = True
+    notify_popup = True
 
     user = User(
         user_id, 
@@ -29,6 +34,10 @@ def get_user_simple():
         user_phone,
         password_hash,
         api_key,
+        notify_email,
+        notify_whatsapp,
+        notify_signal,
+        notify_popup,
         created,
         modified
     )
diff --git a/src/server/BreCal/validators/input_validation.py b/src/server/BreCal/validators/input_validation.py
index 188e5e4..1fb9649 100644
--- a/src/server/BreCal/validators/input_validation.py
+++ b/src/server/BreCal/validators/input_validation.py
@@ -1,8 +1,126 @@
 
 ####################################### InputValidation #######################################
 
+import json
+import datetime
 from abc import ABC, abstractmethod
-from BreCal.schemas.model import Ship, Shipcall, Berth, User, Participant
+from marshmallow import ValidationError
+from string import ascii_letters, digits
+
+from BreCal.schemas.model import Ship, Shipcall, Berth, User, Participant, ShipcallType
+from BreCal.impl.participant import GetParticipant
+from BreCal.impl.ships import GetShips
+from BreCal.impl.berths import GetBerths
+
+from BreCal.database.enums import ParticipantType
+
+
+from BreCal.validators.input_validation_utils import check_if_user_is_bsmd_type, get_participant_id_dictionary, check_if_ship_id_is_valid, check_if_berth_id_is_valid, check_if_participant_ids_are_valid, get_berth_id_dictionary, get_ship_id_dictionary
+from BreCal.validators.validation_base_utils import check_if_string_has_special_characters
+
+def validation_error_default_asserts(response):
+    """creates assertions, when the response does not fail as expected. This function is extensively used in the input validation pytests"""
+    assert response.status_code == 400
+    assert 'message' in list(response.json().keys())
+    return
+
+
+def validate_posted_shipcall_data(user_data:dict, loadedModel:dict, content:dict):
+    """this function applies more complex validation functions to data, which is sent to a post-request of shipcalls"""
+    # DEPRECATED: this function has been refactored into InputValidationShipcall (see methods for POST and PUT evaluation)
+    # #TODO_refactor: this function is pretty complex. One may instead build an object, which calls the methods separately. 
+
+    ##### Section 1: check user_data #####
+    # check, whether the user belongs to a participant, which is of type ParticipantType.BSMD
+    # as ParticipantType is an IntFlag, a user belonging to multiple groups is properly evaluated.
+    is_bsmd = check_if_user_is_bsmd_type(user_data)
+    if not is_bsmd:
+        raise ValidationError(f"current user does not belong to BSMD. Cannot post shipcalls. Found user data: {user_data}")
+    
+    ##### Section 2: check loadedModel #####
+    valid_ship_id = check_if_ship_id_is_valid(ship_id=loadedModel.get("ship_id", None))
+    if not valid_ship_id:
+        raise ValidationError(f"provided an invalid ship id, which is not found in the database: {loadedModel.get('ship_id', None)}")
+    
+    valid_arrival_berth_id = check_if_berth_id_is_valid(berth_id=loadedModel.get("arrival_berth_id", None))
+    if not valid_arrival_berth_id:
+        raise ValidationError(f"provided an invalid arrival berth id, which is not found in the database: {loadedModel.get('arrival_berth_id', None)}")
+    
+    valid_departure_berth_id = check_if_berth_id_is_valid(berth_id=loadedModel.get("departure_berth_id", None))
+    if not valid_departure_berth_id:
+        raise ValidationError(f"provided an invalid departure berth id, which is not found in the database: {loadedModel.get('departure_berth_id', None)}")
+    
+    valid_participant_ids = check_if_participant_ids_are_valid(participants=loadedModel.get("participants",[]))
+    if not valid_participant_ids:
+        raise ValidationError(f"one of the provided participant ids is invalid. Could not find one of these in the database: {loadedModel.get('participants', None)}")   
+
+
+    ##### Section 3: check content #####
+    # loadedModel fills missing values, sometimes using optional values. Hence, check content
+
+    # the following keys should not be set in a POST-request.
+    for forbidden_key in ["canceled", "evaluation", "evaluation_message"]:
+        value = content.get(forbidden_key, None)
+        if value is not None:
+            raise ValidationError(f"'{forbidden_key}' may not be set on POST. Found: {value}")
+        
+    voyage_str_is_invalid = check_if_string_has_special_characters(text=content.get("voyage",""))
+    if voyage_str_is_invalid:
+        raise ValidationError(f"there are invalid characters in the 'voyage'-string. Please use only digits and ASCII letters. Allowed: {ascii_letters+digits}. Found: {content.get('voyage')}")   
+    
+
+    ##### Section 4: check loadedModel & content #####
+    # #TODO_refactor: these methods should be placed in separate locations
+
+    # existance checks in content
+    # datetime checks in loadedModel (datetime.datetime objects). Dates should be in the future. 
+    time_now = datetime.datetime.now()
+    type_ = loadedModel.get("type", int(ShipcallType.undefined))
+    if int(type_)==int(ShipcallType.undefined):
+        raise ValidationError(f"providing 'type' is mandatory. Missing key!")
+    elif int(type_)==int(ShipcallType.arrival):
+        eta = loadedModel.get("eta")
+        if (content.get("eta", None) is None):
+            raise ValidationError(f"providing 'eta' is mandatory. Missing key!")
+        if content.get("arrival_berth_id", None) is None:
+            raise ValidationError(f"providing 'arrival_berth_id' is mandatory. Missing key!")
+        if not eta >= time_now:
+            raise ValidationError(f"'eta' must be in the future. Incorrect datetime provided.")
+    elif int(type_)==int(ShipcallType.departure):
+        etd = loadedModel.get("etd")
+        if (content.get("etd", None) is None):
+            raise ValidationError(f"providing 'etd' is mandatory. Missing key!")
+        if content.get("departure_berth_id", None) is None:
+            raise ValidationError(f"providing 'departure_berth_id' is mandatory. Missing key!")
+        if not etd >= time_now:
+            raise ValidationError(f"'etd' must be in the future. Incorrect datetime provided.")
+    elif int(type_)==int(ShipcallType.shifting):
+        eta = loadedModel.get("eta")
+        etd = loadedModel.get("etd")
+        # * arrival_berth_id / departure_berth_id (depending on type, see above)
+        if (content.get("eta", None) is None) or (content.get("etd", None) is None):
+            raise ValidationError(f"providing 'eta' and 'etd' is mandatory. Missing one of those keys!")
+        if (content.get("arrival_berth_id", None) is None) or (content.get("departure_berth_id", None) is None):
+            raise ValidationError(f"providing 'arrival_berth_id' & 'departure_berth_id' is mandatory. Missing key!")
+        if (not eta >= time_now) or (not etd >= time_now) or (not eta >= etd):
+            raise ValidationError(f"'eta' and 'etd' must be in the future. Incorrect datetime provided.")
+        
+    tidal_window_from = loadedModel.get("tidal_window_from", None)
+    tidal_window_to = loadedModel.get("tidal_window_to", None)
+    if tidal_window_to is not None:
+        if not tidal_window_to >= time_now:
+            raise ValidationError(f"'tidal_window_to' must be in the future. Incorrect datetime provided.")
+
+    if tidal_window_from is not None:
+        if not tidal_window_from >= time_now:
+            raise ValidationError(f"'tidal_window_from' must be in the future. Incorrect datetime provided.")
+        
+    # #TODO: assert tidal_window_from > tidal_window_to
+    
+    # #TODO: len of participants > 0, if agency
+    # * assigned participant for agency
+    return
+
 
 class InputValidation():
     def __init__(self):
@@ -162,4 +280,4 @@ class ParticipantValidation(DataclassValidation):
             ]
         ]
         return all_rules
-    
+
diff --git a/src/server/BreCal/validators/input_validation_ship.py b/src/server/BreCal/validators/input_validation_ship.py
new file mode 100644
index 0000000..eab2480
--- /dev/null
+++ b/src/server/BreCal/validators/input_validation_ship.py
@@ -0,0 +1,140 @@
+import typing
+import json
+import datetime
+from abc import ABC, abstractmethod
+from marshmallow import ValidationError
+from string import ascii_letters, digits
+
+from BreCal.schemas.model import Ship, Shipcall, Berth, User, Participant, ShipcallType
+from BreCal.impl.participant import GetParticipant
+from BreCal.impl.ships import GetShips
+from BreCal.impl.berths import GetBerths
+
+from BreCal.database.enums import ParticipantType, ParticipantFlag
+from BreCal.validators.input_validation_utils import check_if_user_is_bsmd_type, check_if_ship_id_is_valid, check_if_berth_id_is_valid, check_if_participant_ids_are_valid, check_if_participant_ids_and_types_are_valid, get_shipcall_id_dictionary, get_participant_type_from_user_data
+from BreCal.database.sql_handler import execute_sql_query_standalone
+from BreCal.validators.validation_base_utils import check_if_int_is_valid_flag
+from BreCal.validators.validation_base_utils import check_if_string_has_special_characters
+import werkzeug
+
+class InputValidationShip():
+    """
+    This class combines a complex set of individual input validation functions into a joint object.
+    It uses static methods, so the object does not need to be instantiated, but functions can be called immediately.
+
+    Example:
+        InputValidationShip.evaluate(user_data, loadedModel, content)
+
+    When the data violates one of the rules, a marshmallow.ValidationError is raised, which details the issues. 
+    """
+    def __init__(self) -> None:
+        pass
+
+    @staticmethod
+    def evaluate_post_data(user_data:dict, loadedModel:dict, content:dict):
+        # 1.) Only users of type BSMD are allowed to POST
+        InputValidationShip.check_user_is_bsmd_type(user_data)
+
+        # 2.) The ship IMOs are used as matching keys. They must be unique in the database. 
+        InputValidationShip.check_ship_imo_already_exists(loadedModel)
+
+        # 3.) Check for reasonable Values (see BreCal.schemas.model.ShipSchema)
+        InputValidationShip.optionally_evaluate_bollard_pull_value(content)
+        return
+    
+    @staticmethod
+    def evaluate_put_data(user_data:dict, loadedModel:dict, content:dict):
+        # 1.) Only users of type BSMD are allowed to PUT
+        InputValidationShip.check_user_is_bsmd_type(user_data)
+
+        # 2.) The IMO number field may not be changed
+        InputValidationShip.put_content_may_not_contain_imo_number(content)
+
+        # 3.) Check for reasonable Values (see BreCal.schemas.model.ShipSchema)
+        InputValidationShip.optionally_evaluate_bollard_pull_value(content)
+
+        # 4.) ID field is mandatory
+        InputValidationShip.content_contains_ship_id(content)
+        return
+    
+    @staticmethod
+    def evaluate_delete_data(user_data:dict, ship_id:int):
+        # 1.) Only users of type BSMD are allowed to PUT
+        InputValidationShip.check_user_is_bsmd_type(user_data)
+
+        # 2.) The dataset entry may not be deleted already
+        InputValidationShip.check_if_entry_is_already_deleted(ship_id)
+        return
+    
+    @staticmethod
+    def optionally_evaluate_bollard_pull_value(content:dict):
+        bollard_pull = content.get("bollard_pull",None)
+        is_tug = content.get("is_tug", None)
+
+        if bollard_pull is not None:
+            if not is_tug:
+                raise ValidationError(f"'bollard_pull' is only allowed, when a ship is a tug ('is_tug').")
+
+            if (not (0 < bollard_pull < 500)) & (is_tug):
+                raise ValidationError(f"when a ship is a tug, the bollard pull must be 0 < value < 500. ")
+
+    @staticmethod
+    def check_user_is_bsmd_type(user_data:dict):
+        is_bsmd = check_if_user_is_bsmd_type(user_data)
+        if not is_bsmd:
+            raise ValidationError(f"current user does not belong to BSMD. Cannot post, put or delete ships. Found user data: {user_data}")
+        
+    @staticmethod
+    def check_ship_imo_already_exists(loadedModel:dict):
+        # get the ships, convert them to a list of JSON dictionaries
+        response, status_code, header = GetShips(token=None)
+        ships = json.loads(response)
+
+        # extract only the 'imo' values
+        ship_imos = [ship.get("imo") for ship in ships]
+
+        # check, if the imo in the POST-request already exists in the list
+        imo_already_exists = loadedModel.get("imo") in ship_imos
+        if imo_already_exists:
+            raise ValidationError(f"the provided ship IMO {loadedModel.get('imo')} already exists. A ship may only be added, if there is no other ship with the same IMO number.")
+        return
+    
+    @staticmethod
+    def put_content_may_not_contain_imo_number(content:dict):
+        put_data_ship_imo = content.get("imo",None)
+        if put_data_ship_imo is not None:
+            raise ValidationError(f"The IMO number field may not be changed since it serves the purpose of a primary (matching) key.")
+        return
+    
+    @staticmethod
+    def content_contains_ship_id(content:dict):
+        put_data_ship_id = content.get('id',None)
+        if put_data_ship_id is None:
+            raise ValidationError(f"The id field is required.")
+        return
+    
+    @staticmethod
+    def check_if_entry_is_already_deleted(ship_id:int):
+        """
+        When calling a delete request for ships, the dataset may not be deleted already. This method
+        makes sure, that the request contains and ID, has a matching entry in the database, and the
+        database entry may not have a deletion state already.
+        """
+        if ship_id is None:
+            raise ValidationError(f"The ship_id must be provided.")
+        
+        response, status_code, header = GetShips(token=None)
+        ships = json.loads(response)
+        existing_database_entries = [ship for ship in ships if ship.get("id")==ship_id]
+        if len(existing_database_entries)==0:
+            raise ValidationError(f"Could not find a ship with the specified ID. Selected: {ship_id}")
+
+        existing_database_entry = existing_database_entries[0]
+
+        deletion_state = existing_database_entry.get("deleted",None)
+        if deletion_state:
+            raise ValidationError(f"The selected ship entry is already deleted.")
+        return
+
+
+            
diff --git a/src/server/BreCal/validators/input_validation_shipcall.py b/src/server/BreCal/validators/input_validation_shipcall.py
new file mode 100644
index 0000000..0b8ad3b
--- /dev/null
+++ b/src/server/BreCal/validators/input_validation_shipcall.py
@@ -0,0 +1,398 @@
+import typing
+import json
+import datetime
+from abc import ABC, abstractmethod
+from marshmallow import ValidationError
+from string import ascii_letters, digits
+
+from BreCal.schemas.model import Ship, Shipcall, Berth, User, Participant, ShipcallType
+from BreCal.impl.participant import GetParticipant
+from BreCal.impl.ships import GetShips
+from BreCal.impl.berths import GetBerths
+
+from BreCal.database.enums import ParticipantType, ParticipantFlag
+from BreCal.validators.input_validation_utils import check_if_user_is_bsmd_type, check_if_ship_id_is_valid, check_if_berth_id_is_valid, check_if_participant_ids_are_valid, check_if_participant_ids_and_types_are_valid, get_shipcall_id_dictionary, get_participant_type_from_user_data
+from BreCal.database.sql_handler import execute_sql_query_standalone
+from BreCal.validators.validation_base_utils import check_if_int_is_valid_flag
+from BreCal.validators.validation_base_utils import check_if_string_has_special_characters
+import werkzeug
+
+class InputValidationShipcall():
+    """
+    This class combines a complex set of individual input validation functions into a joint object.
+    It uses static methods, so the object does not need to be instantiated, but functions can be called immediately.
+
+    Example:
+        InputValidationShipcall.evaluate(user_data, loadedModel, content)
+
+    When the data violates one of the rules, a marshmallow.ValidationError is raised, which details the issues. 
+
+    """
+    def __init__(self) -> None:
+        pass
+
+    @staticmethod
+    def evaluate_post_data(user_data:dict, loadedModel:dict, content:dict):
+        """
+        this function combines multiple validation functions to verify data, which is sent to the API as a shipcall's POST-request
+        
+        checks:
+            1. permission: only participants that belong to the BSMD group are allowed to POST shipcalls
+            2. reference checks: all refered objects within the Shipcall must exist
+            3. existance of required fields
+            4. reasonable values: validates the values within the Shipcall
+        """
+        # check for permission (only BSMD-type participants)
+        InputValidationShipcall.check_user_is_bsmd_type(user_data)
+
+        # check references (referred IDs must exist)
+        InputValidationShipcall.check_referenced_ids(loadedModel)
+
+        # POST-request only: check the existance of required fields based on the ShipcallType
+        InputValidationShipcall.check_required_fields_exist_based_on_type(loadedModel, content)
+
+        # POST-request only: check the existance of a participant list, when the user is of type agency
+        InputValidationShipcall.check_participant_list_not_empty_when_user_is_agency(loadedModel)
+
+        # check for reasonable values in the shipcall fields
+        InputValidationShipcall.check_shipcall_values(loadedModel, content, forbidden_keys=["canceled", "evaluation", "evaluation_message"])
+        return
+    
+    @staticmethod
+    def evaluate_put_data(user_data:dict, loadedModel:dict, content:dict):
+        """
+        this function combines multiple validation functions to verify data, which is sent to the API as a shipcall's PUT-request
+        
+        checks:
+            1. whether the user belongs to participant group type BSMD
+            2. users of the agency may edit the shipcall, when the shipcall-participant-map entry lists them
+            3. existance of required fields
+            4. all value-rules of the POST evaluation
+            5. a canceled shipcall may not be changed
+        """
+        # check for permission (only BSMD-type participants)
+        # #TODO: are both, bsmd and agency, user types accepted?
+        InputValidationShipcall.check_user_is_bsmd_type(user_data)
+
+        # check, whether an agency is listed in the shipcall-participant-map
+        InputValidationShipcall.check_agency_in_shipcall_participant_map(user_data, loadedModel, content)
+
+        # the ID field is required, all missing fields will be ignored in the update
+        InputValidationShipcall.check_required_fields_of_put_request(content)
+
+        # check for reasonable values in the shipcall fields and checks for forbidden keys. 
+        InputValidationShipcall.check_shipcall_values(loadedModel, content, forbidden_keys=["evaluation", "evaluation_message"])
+
+        # a canceled shipcall cannot be selected
+        # Note: 'canceled' is allowed in PUT-requests, if it is not already set (which is checked by InputValidationShipcall.check_shipcall_is_cancel)
+        InputValidationShipcall.check_shipcall_is_canceled(loadedModel, content)
+        return
+    
+    @staticmethod
+    def check_shipcall_values(loadedModel:dict, content:dict, forbidden_keys:list=["canceled", "evaluation", "evaluation_message"]):
+        """
+        individually checks each value provided in the loadedModel/content. 
+        This function validates, whether the values are reasonable.
+
+        Also, some data may not be set in a POST-request.
+        """
+        # Note: BreCal.schemas.model.ShipcallSchema has an internal validation, which the marshmallow library provides. This is used
+        # to verify values individually, when the schema is loaded with data.
+        # This function focuses on more complex input validation, which may require more sophisticated methods
+
+        # loadedModel fills missing values, sometimes using optional values. Hence, the 'content'-variable is prefered for some of these verifications
+        # voyage shall not contain special characters
+        voyage_str_is_invalid = check_if_string_has_special_characters(text=content.get("voyage",""))
+        if voyage_str_is_invalid:
+            raise ValidationError(f"there are invalid characters in the 'voyage'-string. Please use only digits and ASCII letters. Allowed: {ascii_letters+digits}. Found: {content.get('voyage')}")   
+        
+        # the 'flags' integer must be valid
+        flags_value = content.get("flags", 0)
+        if check_if_int_is_valid_flag(flags_value, enum_object=ParticipantFlag):
+            raise ValidationError(f"incorrect value provided for 'flags'. Must be a valid combination of the flags.")
+        
+        # time values must use future-dates
+        InputValidationShipcall.check_times_are_in_future(loadedModel, content)
+
+        # some arguments must not be provided
+        InputValidationShipcall.check_forbidden_arguments(content, forbidden_keys=forbidden_keys)
+        return
+    
+    @staticmethod
+    def check_agency_in_shipcall_participant_map(user_data:dict, loadedModel:dict, content:dict, spm_shipcall_data:typing.Optional[list]=None):
+        """
+        When the request is issued by a user of type 'AGENCY', there must be special caution. Agency users cannot self-assign as participants
+        of a shipcall. Further, when no AGENCY is assigned to the shipcall, a PUT-request is not feasible. In those cases, the
+        BSMD must first assign an agency, before a PUT-request can assign further participants.
+
+        Upon violation, this method issues 'Forbidden'-Exceptions with HTTP status code 403. There are four reasons for violations:
+        a) an agency tries to self-assign for a shipcall
+        b) there is no assigned agency for the current shipcall
+        c) an agency is assigned, but the current agency-user belongs to a different participant_id 
+        d) the user must be of ParticipantType BSMD or AGENCY
+
+        args:
+            spm_shipcall_data: 
+                a list of entries obtained from the ShipcallParticipantMap. These are deserialized dictionaries.
+                e.g., [{'participant_id': 136, 'type': 8}, ]
+        """
+        if spm_shipcall_data is None:
+            # read the ShipcallParticipantMap entry of the current shipcall_id. This is used within the input validation of a PUT request
+            spm_shipcall_data = execute_sql_query_standalone(
+                query = "SELECT participant_id, type FROM shipcall_participant_map WHERE shipcall_id=?shipcall_id?", 
+                param={"shipcall_id":loadedModel["id"]},
+                pooledConnection=None
+                )
+        
+        # which role should be set by the PUT request? If the agency is about to be set, an error will be created
+        # read the user data from the JWT token (set when login is performed)
+        user_type = get_participant_type_from_user_data(user_data) # decode JWT -> get 'type' value
+
+        # select the matching entries from the ShipcallParticipantMap
+        agency_entries = [spm_entry for spm_entry in spm_shipcall_data if int(spm_entry.get("type"))==int(ParticipantType.AGENCY)] # find all entries of type AGENCY (there should be at max. 1)
+
+        # when the request stems from an AGENCY user, and the user wants to PUT an AGENCY role, the request should fail
+        # boolean: check, whether any of the assigned participants is of type AGENCY
+        types = [participant.get("type") for participant in loadedModel["participants"]] # readout the participants from the loadedModel, which shall be assigned by the PUT request
+        any_type_is_agency = any([int(type_) == int(ParticipantType.AGENCY) for type_ in types]) # check, whether *any* of the participants is an agency
+
+        if not (int(user_type) in [int(ParticipantType.AGENCY), int(ParticipantType.BSMD)]):
+            # user not AGENCY or BSMD
+            raise werkzeug.exceptions.Forbidden(f"PUT Requests for shipcalls can only be issued by AGENCY or BSMD users.") # Forbidden: 403
+
+        if (int(user_type) == int(ParticipantType.AGENCY)) & (any_type_is_agency):
+            # self-assignment: agency sets agency participant
+            raise werkzeug.exceptions.Forbidden(f"An agency cannot self-register for a shipcall. The request is issued by an agency-user and tries to assign an AGENCY as the participant of the shipcall.") # Forbidden: 403
+
+        if len(agency_entries)>0:
+            # agency participant exists: participant id must be the same as shipcall participant map entry
+            matching_spm_entry = [spm_entry for spm_entry in spm_shipcall_data if (spm_entry.get("participant_id")==user_data["id"]) & (int(spm_entry.get("type"))==int(ParticipantType.AGENCY))]
+            
+            if len(matching_spm_entry)==0:
+                # An AGENCY was found, but a different participant_id is assigned to that AGENCY
+                raise werkzeug.exceptions.Forbidden(f"A different participant_id is assigned as the AGENCY of this shipcall. Provided ID: {user_data.get('id')}, Assigned ShipcallParticipantMap: {agency_entries}") # Forbidden: 403
+            else:
+                # a matching agency was found: no violation
+                return
+
+        else:
+            # agency participant does not exist: there is no assigned agency role for the shipcall {shipcall_id}
+            raise werkzeug.exceptions.Forbidden(f"There is no assigned agency for this shipcall. Shipcall ID: {loadedModel['id']}") # Forbidden: 403
+        return
+    
+    @staticmethod
+    def check_user_is_bsmd_type(user_data):
+        """
+        check, whether the user belongs to a participant, which is of type ParticipantType.BSMD
+        as ParticipantType is an IntFlag, a user belonging to multiple groups is properly evaluated.
+        """
+        is_bsmd = check_if_user_is_bsmd_type(user_data)
+        if not is_bsmd:
+            raise ValidationError(f"current user does not belong to BSMD. Cannot post or put shipcalls. Found user data: {user_data}")
+        return
+    
+    @staticmethod
+    def check_referenced_ids(loadedModel):
+        """
+        check, whether the referenced entries exist (e.g., when a Ship ID is referenced, but does not exist, the validation fails)
+        """
+        # get all IDs from the loadedModel
+        ship_id = loadedModel.get("ship_id", None)
+        arrival_berth_id = loadedModel.get("arrival_berth_id", None)
+        departure_berth_id = loadedModel.get("departure_berth_id", None)
+        participants = loadedModel.get("participants",[])
+
+        valid_ship_id = check_if_ship_id_is_valid(ship_id=ship_id)
+        if not valid_ship_id:
+            raise ValidationError(f"provided an invalid ship id, which is not found in the database: {ship_id}")
+        
+        valid_arrival_berth_id = check_if_berth_id_is_valid(berth_id=arrival_berth_id)
+        if not valid_arrival_berth_id:
+            raise ValidationError(f"provided an invalid arrival berth id, which is not found in the database: {arrival_berth_id}")
+        
+        valid_departure_berth_id = check_if_berth_id_is_valid(berth_id=departure_berth_id)
+        if not valid_departure_berth_id:
+            raise ValidationError(f"provided an invalid departure berth id, which is not found in the database: {departure_berth_id}")
+        
+        valid_participant_ids = check_if_participant_ids_are_valid(participants=participants)
+        if not valid_participant_ids:
+            raise ValidationError(f"one of the provided participant ids is invalid. Could not find one of these in the database: {participants}")
+        
+        valid_participant_types = check_if_participant_ids_and_types_are_valid(participants=participants)
+        if not valid_participant_types:
+            raise ValidationError(f"every participant id and type should be listed only once. Found multiple entries for one of the participants.")
+        
+    @staticmethod
+    def check_forbidden_arguments(content:dict, forbidden_keys=["canceled", "evaluation", "evaluation_message"]):
+        """
+        a post-request must not contain the arguments 'canceled', 'evaluation', 'evaluation_message'.
+        a put-request must not contain the arguments 'evaluation', 'evaluation_message'
+        
+        """
+        # the following keys should not be set in a POST-request.
+        for forbidden_key in forbidden_keys:
+            value = content.get(forbidden_key, None)
+            if value is not None:
+                raise ValidationError(f"'{forbidden_key}' may not be set on POST. Found: {value}")
+        return            
+
+    @staticmethod
+    def check_required_fields_exist_based_on_type(loadedModel:dict, content:dict):
+        """
+        depending on the ShipcallType, some fields are *required* in a POST-request
+        """
+        type_ = loadedModel.get("type", int(ShipcallType.undefined))
+        ship_id = content.get("ship_id", None)
+        eta = content.get("eta", None)
+        etd = content.get("etd", None)
+        arrival_berth_id = content.get("arrival_berth_id", None)
+        departure_berth_id = content.get("departure_berth_id", None)
+
+        if ship_id is None:
+                raise ValidationError(f"providing 'ship_id' is mandatory. Missing key!")
+
+        if int(type_)==int(ShipcallType.undefined):
+            raise ValidationError(f"providing 'type' is mandatory. Missing key!")
+        
+        # arrival: arrival_berth_id & eta must exist
+        elif int(type_)==int(ShipcallType.arrival):
+            if eta is None:
+                raise ValidationError(f"providing 'eta' is mandatory. Missing key!")
+            
+            if arrival_berth_id is None:
+                raise ValidationError(f"providing 'arrival_berth_id' is mandatory. Missing key!")
+                
+        # departure: departive_berth_id and etd must exist
+        elif int(type_)==int(ShipcallType.departure):
+            if etd is None:
+                raise ValidationError(f"providing 'etd' is mandatory. Missing key!")
+            
+            if departure_berth_id is None:
+                raise ValidationError(f"providing 'departure_berth_id' is mandatory. Missing key!")
+            
+        # shifting: arrival_berth_id, departure_berth_id, eta and etd must exist
+        elif int(type_)==int(ShipcallType.shifting):
+            if (eta is None) or (etd is None):
+                raise ValidationError(f"providing 'eta' and 'etd' is mandatory. Missing one of those keys!")
+            if (arrival_berth_id is None) or (departure_berth_id is None):
+                raise ValidationError(f"providing 'arrival_berth_id' & 'departure_berth_id' is mandatory. Missing key!")
+            
+        else:
+            raise ValidationError(f"incorrect 'type' provided!")
+        return
+
+    @staticmethod
+    def check_times_are_in_future(loadedModel:dict, content:dict):
+        """
+        Dates should be in the future. Depending on the ShipcallType, specific values should be checked
+        Perfornms datetime checks in the loadedModel (datetime.datetime objects). 
+        """
+        # obtain the current datetime to check, whether the provided values are in the future
+        time_now = datetime.datetime.now()
+
+        type_ = loadedModel.get("type", int(ShipcallType.undefined))
+        eta = loadedModel.get("eta")
+        etd = loadedModel.get("etd")
+        tidal_window_from = loadedModel.get("tidal_window_from", None)
+        tidal_window_to = loadedModel.get("tidal_window_to", None)
+
+        # Estimated arrival or departure times
+        InputValidationShipcall.check_times_in_future_based_on_type(type_, time_now, eta, etd)
+            
+        # Tidal Window
+        InputValidationShipcall.check_tidal_window_in_future(time_now, tidal_window_from, tidal_window_to)
+        return
+    
+    @staticmethod
+    def check_times_in_future_based_on_type(type_, time_now, eta, etd):
+        """
+        checks, whether the ETA & ETD times are in the future.
+        based on the type, this function checks:
+            arrival: eta
+            departure: etd
+            shifting: eta & etd
+        """
+        if int(type_)==int(ShipcallType.undefined):
+            raise ValidationError(f"providing 'type' is mandatory. Missing key!")
+        elif int(type_)==int(ShipcallType.arrival):
+            if not eta > time_now:
+                raise ValidationError(f"'eta' must be in the future. Incorrect datetime provided. Current Time: {time_now}. ETA: {eta}.")
+        elif int(type_)==int(ShipcallType.departure):
+            if not etd > time_now:
+                raise ValidationError(f"'etd' must be in the future. Incorrect datetime provided. Current Time: {time_now}. ETD: {etd}.")
+        elif int(type_)==int(ShipcallType.shifting):
+            if (not eta > time_now) or (not etd > time_now):
+                raise ValidationError(f"'eta' and 'etd' must be in the future. Incorrect datetime provided. Current Time: {time_now}. ETA: {eta}. ETD: {etd}")
+            if (not etd > eta):
+                raise ValidationError(f"'etd' must be larger than 'eta'. The ship cannot depart, before it has arrived. Found: ETA {eta}, ETD: {etd}")
+        return
+    
+    @staticmethod
+    def check_tidal_window_in_future(time_now, tidal_window_from, tidal_window_to):
+        if tidal_window_to is not None:
+            if not tidal_window_to >= time_now:
+                raise ValidationError(f"'tidal_window_to' must be in the future. Incorrect datetime provided.")
+
+        if tidal_window_from is not None:
+            if not tidal_window_from >= time_now:
+                raise ValidationError(f"'tidal_window_from' must be in the future. Incorrect datetime provided.")
+            
+        if (tidal_window_to is not None) and (tidal_window_from is not None):
+            if tidal_window_to < tidal_window_from:
+                raise ValidationError(f"'tidal_window_to' must take place after 'tidal_window_from'. Incorrect datetime provided. Found 'tidal_window_to': {tidal_window_to}, 'tidal_window_from': {tidal_window_to}.")
+        return
+    
+    @staticmethod
+    def check_participant_list_not_empty_when_user_is_agency(loadedModel):
+        """
+        For each POST request, one of the participants in the list must be assigned as a ParticipantType.AGENCY
+        """
+        participants = loadedModel.get("participants", [])
+        is_agency_participant = [ParticipantType.AGENCY in ParticipantType(participant.get("type")) for participant in participants]
+
+        if not any(is_agency_participant): 
+            raise ValidationError(f"One of the assigned participants *must* be of type 'ParticipantType.AGENCY'. Found list of participants: {participants}")
+        return
+    
+    @staticmethod
+    def check_shipcall_is_canceled(loadedModel, content):
+        # read the shipcall_id from the PUT data
+        shipcall_id = loadedModel.get("id")
+
+        # get all shipcalls in the database
+        shipcalls = get_shipcall_id_dictionary()
+
+        # search for the matching shipcall in the database
+        shipcall = shipcalls.get(shipcall_id,{})
+
+        # if the *existing* shipcall in the database is canceled, it may not be changed
+        if shipcall.get("canceled", False):
+            raise ValidationError(f"The shipcall with id 'shipcall_id' is canceled. A canceled shipcall may not be changed.")
+        return
+    
+    @staticmethod
+    def check_required_fields_of_put_request(content:dict):
+        shipcall_id = content.get("id", None)
+        if shipcall_id is None:
+            raise ValidationError(f"A PUT request requires an 'id' to refer to.")
+        
+    
+
+"""
+# copy
+def validate_posted_shipcall_data(user_data:dict, loadedModel:dict, content:dict):
+    ##### Section 1: check user_data #####
+    # DONE: refactored
+    
+    ##### Section 2: check loadedModel #####
+    # DONE: refactored
+
+    ##### Section 3: check content #####
+    # DONE: refactored
+    
+
+    ##### Section 4: check loadedModel & content #####
+    # DONE: refactored ET and BERTH ID existance check
+    # DONE: refactored 'time in future' checks
+    return
+"""
\ No newline at end of file
diff --git a/src/server/BreCal/validators/input_validation_times.py b/src/server/BreCal/validators/input_validation_times.py
new file mode 100644
index 0000000..6b8ab6a
--- /dev/null
+++ b/src/server/BreCal/validators/input_validation_times.py
@@ -0,0 +1,402 @@
+import typing
+import json
+import datetime
+from abc import ABC, abstractmethod
+from marshmallow import ValidationError
+from string import ascii_letters, digits
+
+from BreCal.schemas.model import Ship, Shipcall, Berth, User, Participant, ShipcallType, Times
+from BreCal.impl.participant import GetParticipant
+from BreCal.impl.ships import GetShips
+from BreCal.impl.berths import GetBerths
+from BreCal.impl.times import GetTimes
+
+from BreCal.database.enums import ParticipantType, ParticipantFlag
+from BreCal.validators.input_validation_utils import check_if_user_is_bsmd_type, check_if_ship_id_is_valid, check_if_berth_id_is_valid, check_if_participant_ids_are_valid, check_if_participant_ids_and_types_are_valid, check_if_shipcall_id_is_valid, get_shipcall_id_dictionary, get_participant_type_from_user_data, get_participant_id_dictionary, check_if_participant_id_is_valid_standalone
+from BreCal.database.sql_handler import execute_sql_query_standalone
+from BreCal.validators.validation_base_utils import check_if_int_is_valid_flag, check_if_string_has_special_characters
+import werkzeug
+
+def build_post_data_type_dependent_required_fields_dict()->dict[ShipcallType,dict[ParticipantType,typing.Optional[list[str]]]]:
+    """
+    The required fields of a POST-request depend on ShipcallType and ParticipantType. This function creates
+    a dictionary, which maps those types to a list of required fields.
+
+    The participant types 'undefined' and 'bsmd' should not be used in POST-requests. They return 'None'. 
+    """
+    post_data_type_dependent_required_fields_dict = {
+        ShipcallType.arrival:{
+            ParticipantType.undefined:None, # should not be set in POST requests
+            ParticipantType.BSMD:None, # should not be set in POST requests
+            ParticipantType.TERMINAL:["operations_start"],
+            ParticipantType.AGENCY:["eta_berth"],
+            ParticipantType.MOORING:["eta_berth"],
+            ParticipantType.PILOT:["eta_berth"],
+            ParticipantType.PORT_ADMINISTRATION:["eta_berth"],
+            ParticipantType.TUG:["eta_berth"],
+        },
+        ShipcallType.departure:{
+            ParticipantType.undefined:None, # should not be set in POST requests
+            ParticipantType.BSMD:None, # should not be set in POST requests
+            ParticipantType.TERMINAL:["operations_end"],
+            ParticipantType.AGENCY:["etd_berth"],
+            ParticipantType.MOORING:["etd_berth"],
+            ParticipantType.PILOT:["etd_berth"],
+            ParticipantType.PORT_ADMINISTRATION:["etd_berth"],
+            ParticipantType.TUG:["etd_berth"],
+        },
+        ShipcallType.shifting:{
+            ParticipantType.undefined:None, # should not be set in POST requests
+            ParticipantType.BSMD:None, # should not be set in POST requests
+            ParticipantType.TERMINAL:["operations_start", "operations_end"],
+            ParticipantType.AGENCY:["eta_berth", "etd_berth"],
+            ParticipantType.MOORING:["eta_berth", "etd_berth"],
+            ParticipantType.PILOT:["eta_berth", "etd_berth"],
+            ParticipantType.PORT_ADMINISTRATION:["eta_berth", "etd_berth"],
+            ParticipantType.TUG:["eta_berth", "etd_berth"],
+        },
+    }
+    return post_data_type_dependent_required_fields_dict
+
+
+
+class InputValidationTimes():
+    """
+    This class combines a complex set of individual input validation functions into a joint object.
+    It uses static methods, so the object does not need to be instantiated, but functions can be called immediately.
+
+    Example:
+        InputValidationTimes.evaluate(user_data, loadedModel, content)
+
+    When the data violates one of the rules, a marshmallow.ValidationError is raised, which details the issues. 
+    """
+    def __init__(self) -> None:
+        pass
+
+    @staticmethod
+    def evaluate_post_data(user_data:dict, loadedModel:dict, content:dict):
+        # 0.) Check for the presence of required fields
+        InputValidationTimes.check_times_required_fields_post_data(loadedModel, content)
+
+        # 1.) datasets may only be created, if the current user fits the appropriate type in the ShipcallParticipantMap
+        InputValidationTimes.check_if_user_fits_shipcall_participant_map(user_data, loadedModel, content)
+
+        # 2.) datasets may only be created, if the respective participant type did not already create one.
+        InputValidationTimes.check_if_entry_already_exists_for_participant_type(user_data, loadedModel, content)
+
+        # 3.) only users who are *not* of type BSMD may post times datasets.
+        InputValidationTimes.check_user_is_not_bsmd_type(user_data)
+    
+        # 4.) Reference checking
+        InputValidationTimes.check_dataset_references(content)
+
+        # 5.) Value checking
+        InputValidationTimes.check_dataset_values(user_data, loadedModel, content)
+        return
+    
+    @staticmethod
+    def evaluate_put_data(user_data:dict, loadedModel:dict, content:dict):
+        # 1.) Check for the presence of required fields
+        InputValidationTimes.check_times_required_fields_put_data(content)
+
+        # 2.) Only users of the same participant_id, which the times dataset refers to, can update the entry
+        InputValidationTimes.check_user_belongs_to_same_group_as_dataset_determines(user_data, loadedModel=loadedModel, times_id=None)
+
+        # 3.) Reference checking
+        InputValidationTimes.check_dataset_references(content)
+
+        # 4.) Value checking
+        InputValidationTimes.check_dataset_values(user_data, loadedModel, content)
+        return
+    
+    @staticmethod
+    def evaluate_delete_data(user_data:dict, times_id:int):
+        # #TODO_determine: is times_id always an int or does the request.args call provide a string?
+        times_id = int(times_id) if not isinstance(times_id, int) else times_id
+
+        # 1.) The dataset entry may not be deleted already
+        InputValidationTimes.check_if_entry_is_already_deleted(times_id)
+
+        # 2.) Only users of the same participant_id, which the times dataset refers to, can delete the entry
+        InputValidationTimes.check_user_belongs_to_same_group_as_dataset_determines(user_data, loadedModel=None, times_id=times_id)
+        return
+    
+    @staticmethod
+    def check_if_entry_is_already_deleted(times_id:int):
+        """
+        When calling a delete request for times, the dataset may not be deleted already. This method
+        makes sure, that the request contains and ID, has a matching entry in the database. 
+        When a times dataset is deleted, it is directly removed from the database. 
+
+        To identify deleted entries, query from the database and check, whether there is a match for the times id.
+
+        """
+        # perform an SQL query. Creates a pooled connection internally, queries the database, then closes the connection.
+        query = "SELECT shipcall_id FROM times WHERE id = ?id?"
+        pdata = execute_sql_query_standalone(query=query, param={"id":times_id}, pooledConnection=None)
+
+        if len(pdata)==0:
+            raise ValidationError(f"The selected time entry is already deleted. ID: {times_id}")
+        return
+
+    @staticmethod
+    def check_user_is_not_bsmd_type(user_data:dict):
+        """a new dataset may only be created by a user who is *not* belonging to participant group BSMD"""
+        is_bsmd = check_if_user_is_bsmd_type(user_data)
+        if is_bsmd:
+            raise ValidationError(f"current user belongs to BSMD. Cannot post 'times' datasets. Found user data: {user_data}")
+        return
+    
+    @staticmethod
+    def check_dataset_values(user_data:dict, loadedModel:dict, content:dict):
+        """
+        this method validates POST and PUT data. Most of the dataset arguments are validated directly in the 
+        BreCal.schemas.model.TimesSchema, using @validates. This is exclusive for 'simple' validation rules. 
+
+        This applies to:
+            "remarks" & "berth_info"
+            "eta_berth", "etd_berth", "lock_time", "zone_entry", "operations_start", "operations_end"
+        """
+        # while InputValidationTimes.check_user_is_not_bsmd_type already validates a user, this method
+        # validates the times dataset. 
+
+        # ensure loadedModel["participant_type"] is of type ParticipantType
+        if not isinstance(loadedModel["participant_type"], ParticipantType):
+            loadedModel["participant_type"] = ParticipantType(loadedModel["participant_type"])
+
+        if ParticipantType.BSMD in loadedModel["participant_type"]:
+            raise ValidationError(f"current user belongs to BSMD. Cannot post times datasets. Found user data: {user_data}")
+        return
+    
+    @staticmethod
+    def check_dataset_references(content:dict):
+        """
+        When IDs are referenced, they must exist in the database. This method individually validates the existance of referred
+        berth ID, participant IDs and shipcall ID.
+
+        Note: whenever an ID is 'None', there is no exception, because a different method is supposed to capture non-existant mandatory fields.
+        """
+        # extract the IDs
+        berth_id, participant_id, shipcall_id = content.get("berth_id"), content.get("participant_id"), content.get("shipcall_id")
+
+        valid_berth_id_reference = check_if_berth_id_is_valid(berth_id)
+        if not valid_berth_id_reference:
+            raise ValidationError(f"The referenced berth_id '{berth_id}' does not exist in the database.")
+        
+        valid_shipcall_id_reference = check_if_shipcall_id_is_valid(shipcall_id)
+        if not valid_shipcall_id_reference:
+            raise ValidationError(f"The referenced shipcall_id '{shipcall_id}' does not exist in the database.")
+        
+        valid_participant_id_reference = check_if_participant_id_is_valid_standalone(participant_id)
+        if not valid_participant_id_reference:
+            raise ValidationError(f"The referenced participant_id '{participant_id}' does not exist in the database.")
+        
+        return
+    
+    @staticmethod
+    def check_times_required_fields_post_data(loadedModel:dict, content:dict):
+        """
+        Depending on ShipcallType and ParticipantType, there is a rather complex set of required fields.
+        Independent of those types, any POST request for times should always include the default fields. 
+
+        The dependent and independent fields are validated by checking, whether the respective value in 'content'
+        is undefined (returns None). When any of these fields is undefined, a ValidationError is raised. 
+        """
+        participant_type = loadedModel["participant_type"]
+        shipcall_id = loadedModel["shipcall_id"]
+
+        # build a dictionary of id:item pairs, so one can select the respective participant
+        # must look-up the shipcall_type based on the shipcall_id
+        shipcalls = get_shipcall_id_dictionary()
+        shipcall_type = ShipcallType[shipcalls.get(shipcall_id,{}).get("type",ShipcallType.undefined.name)]
+
+        if (participant_type is None) or (int(shipcall_type) == int(ShipcallType.undefined)):
+            raise ValidationError(f"At least one of the required fields is missing. Missing: 'participant_type' or 'shipcall_type'")
+
+
+        # build a list of required fields based on shipcall and participant type, as well as type-independent fields
+        independent_required_fields = InputValidationTimes.get_post_data_type_independent_fields()
+        dependent_required_fields = InputValidationTimes.get_post_data_type_dependent_fields(shipcall_type, participant_type)
+
+        required_fields = independent_required_fields + dependent_required_fields
+
+        # generate a list of booleans, where each element shows, whether one of the required fields is missing.
+        missing_required_fields = [
+            content.get(field,None) is None for field in required_fields
+        ]
+
+        if any(missing_required_fields):
+            # create a tuple of (field_key, bool) to describe to a user, which one of the fields may be missing
+            verbosity_tuple = [(field, missing) for field, missing in zip(required_fields, missing_required_fields) if missing]
+            raise ValidationError(f"At least one of the required fields is missing. Missing: {verbosity_tuple}")
+        return
+    
+    @staticmethod
+    def check_times_required_fields_put_data(content:dict):
+        """in a PUT request, only the 'id' is a required field. All other fields are simply ignored, when they are not provided."""
+        if content.get("id") is None:
+            raise ValidationError(f"A PUT-request requires an 'id' reference, which was not found.")
+        return
+    
+    @staticmethod
+    def get_post_data_type_independent_fields()->list[str]:
+        """
+        Independent of the ShipcallType and ParticipantType, any POST request for times should always include the default fields.
+        """
+        independent_required_fields = [
+            "shipcall_id", "participant_id", "participant_type"
+        ]
+        return independent_required_fields
+    
+    @staticmethod
+    def get_post_data_type_dependent_fields(shipcall_type:typing.Union[int, ShipcallType], participant_type:typing.Union[int, ParticipantType]):
+        """
+        Depending on ShipcallType and ParticipantType, there is a rather complex set of required fields.
+
+        Arriving shipcalls need arrival times (e.g., 'eta'), Departing shipcalls need departure times (e.g., 'etd') and 
+        Shifting shipcalls need both times (e.g., 'eta' and 'etd'). 
+
+        Further, the ParticipantType determines the set of relevant times. In particular, the terminal uses 
+        'operations_start' and 'operations_end', while other users use 'eta_berth' or 'etd_berth'.
+        """
+        # ensure that both, shipcall_type and participant_type, refer to the enumerators, as opposed to integers.
+        if not isinstance(shipcall_type, ShipcallType):
+            shipcall_type = ShipcallType(shipcall_type)
+        if not isinstance(participant_type, ParticipantType):
+            participant_type = ParticipantType(participant_type)
+
+        # build a dictionary, which maps shipcall type and participant type to a list of fields
+        dependent_required_fields_dict = build_post_data_type_dependent_required_fields_dict()
+
+        # select shipcall type &  participant type
+        dependent_required_fields = dependent_required_fields_dict.get(shipcall_type,{}).get(participant_type,None)
+        return dependent_required_fields
+    
+    @staticmethod
+    def check_if_user_fits_shipcall_participant_map(user_data:dict, loadedModel:dict, content:dict, spm_shipcall_data=None):
+        """
+        a new dataset may only be created, if the user belongs to the participant group (participant_id),
+        which is assigned to the shipcall within the ShipcallParticipantMap
+
+        This method does not validate, what the POST-request contains, but it validates, whether the *user* is
+        authorized to send the request. 
+
+        options:
+            spm_shipcall_data: 
+                data from the ShipcallParticipantMap, which refers to the respective shipcall ID. The SPM can be
+                an optional argument to allow for much easier unit testing. 
+        """
+            
+        # identify shipcall_id
+        shipcall_id = loadedModel["shipcall_id"]
+
+        # identify user's participant_id & type (get all participants; then filter these for the {participant_id})
+        participant_id = user_data["participant_id"] #participants = get_participant_id_dictionary() #participant_type = ParticipantType(participants.get(participant_id,{}).get("type"))
+        participant_type = ParticipantType(loadedModel["participant_type"]) if not isinstance(loadedModel["participant_type"],ParticipantType) else loadedModel["participant_type"]
+
+        # get ShipcallParticipantMap for the shipcall_id
+        if spm_shipcall_data is None:
+            # read the ShipcallParticipantMap entry of the current shipcall_id. This is used within the input validation of a PUT request
+            # creates a list of {'participant_id: ..., 'type': ...} elements
+            spm_shipcall_data = execute_sql_query_standalone(
+                query = "SELECT participant_id, type FROM shipcall_participant_map WHERE shipcall_id=?shipcall_id?", 
+                param={"shipcall_id":shipcall_id},
+                pooledConnection=None
+                )
+
+        # check, if participant_id is assigned to the ShipcallParticipantMap
+        matching_spm = [
+            spm
+            for spm in spm_shipcall_data
+            if spm.get("participant_id")==participant_id
+        ]
+
+        if not len(matching_spm)>0:
+            raise ValidationError(f'The participant group with id {participant_id} is not assigned to the shipcall. Found ShipcallParticipantMap: {spm_shipcall_data}')
+
+        # check, if the assigned participant_id is assigned with the same role
+        matching_spm_element = matching_spm[0]
+        matching_spm_element_participant_type = ParticipantType(matching_spm_element.get("type"))
+        if not matching_spm_element_participant_type in participant_type:
+            raise ValidationError(f'The participant group with id {participant_id} is assigned to the shipcall in a different role. Request Role: {participant_type}, ShipcallParticipantMap Role Assignment: {matching_spm_element_participant_type}')
+        return
+    
+    @staticmethod
+    def check_if_entry_already_exists_for_participant_type(user_data:dict, loadedModel:dict, content:dict):
+        """determines, whether a dataset for the participant type is already present"""
+        # determine participant_type and shipcall_id from the loadedModel
+        participant_type = loadedModel["participant_type"]
+        if not isinstance(participant_type, ParticipantType): # ensure the correct data type
+            participant_type = ParticipantType(participant_type)
+        shipcall_id = loadedModel["shipcall_id"]
+
+        # get all times entries of the shipcall_id from the database
+        times, status_code, headers = GetTimes(options={"shipcall_id":shipcall_id})
+        times = json.loads(times)
+
+        # check, if there is already a dataset for the participant type
+        participant_type_exists_already = any([ParticipantType(time_.get("participant_type",0)) in participant_type for time_ in times])
+        if participant_type_exists_already:
+            raise ValidationError(f"A dataset for the participant type is already present. Participant Type: {participant_type}. Times Datasets: {times}")
+        return
+    
+    @staticmethod
+    def check_user_belongs_to_same_group_as_dataset_determines(user_data:dict, loadedModel:typing.Optional[dict]=None, times_id:typing.Optional[int]=None):
+        """
+        This method checks, whether a user belongs to the same participant_id, as the dataset entry refers to.
+        It is used in, both, PUT requests and DELETE requests, but uses different arguments to determine the matching
+        time dataset entry.
+
+        PUT:
+            loadedModel is unbundled to identify the matching times entry by the shipcall id
+
+        DELETE:
+            times_id is used to directly identify the matching times entry
+        """
+        assert not ((loadedModel is None) and (times_id is None)), f"must provide either loadedModel OR times_id. Both are 'None'"
+        assert (loadedModel is None) or (times_id is None), f"must provide either loadedModel OR times_id. Both are defined."
+
+        # identify the user's participant id
+        user_participant_id = user_data["participant_id"]
+
+        if loadedModel is not None:
+            shipcall_id = loadedModel["shipcall_id"]
+            participant_type = loadedModel["participant_type"]
+
+            # get all times entries of the shipcall_id from the database as a list of {'participant_id':..., 'participant_type':...} elements
+            query = "SELECT participant_id, participant_type FROM times WHERE shipcall_id = ?shipcall_id?"
+            times = execute_sql_query_standalone(query=query, param={"shipcall_id":shipcall_id}, pooledConnection=None)
+
+            # get the matching datasets, where the participant id is identical
+            time_datasets_of_participant_type = [time_ for time_ in times if time_.get("participant_type")==participant_type]
+
+            # when there are no matching participants, raise a ValidationError
+            if not len(time_datasets_of_participant_type)>0:
+                raise ValidationError(f"Could not find a matching time dataset for the provided participant_type: {participant_type}. Found Time Datasets: {times}")
+            
+            # take the first match. There should always be only one match. 
+            time_datasets_of_participant_type = time_datasets_of_participant_type[0]
+            participant_id_of_times_dataset = time_datasets_of_participant_type.get("participant_id")
+
+        if times_id is not None:
+            # perform an SQL query. Creates a pooled connection internally, queries the database, then closes the connection.
+            query = "SELECT participant_id FROM times WHERE id = ?id?"
+            pdata = execute_sql_query_standalone(query=query, param={"id":times_id}, pooledConnection=None)
+
+            # extracts the participant_id from the first matching entry, if applicable
+            if not len(pdata)>0:
+                # this case is usually covered by the InputValidationTimes.check_if_entry_is_already_deleted method already
+                raise ValidationError(f"Unknown times_id. Could not find a matching entry for ID: {times_id}")
+            else:
+                participant_id_of_times_dataset = pdata[0].get("participant_id")
+
+        if user_participant_id != participant_id_of_times_dataset:
+            raise ValidationError(f"The dataset may only be changed by a user belonging to the same participant group as the times dataset is referring to. User participant_id: {user_participant_id}; Dataset participant_id: {participant_id_of_times_dataset}")
+        return
+
+    
+
+    
+
+
+            
diff --git a/src/server/BreCal/validators/input_validation_utils.py b/src/server/BreCal/validators/input_validation_utils.py
new file mode 100644
index 0000000..325e3fb
--- /dev/null
+++ b/src/server/BreCal/validators/input_validation_utils.py
@@ -0,0 +1,182 @@
+import logging
+import json
+from collections import Counter
+
+from BreCal.impl.participant import GetParticipant
+from BreCal.impl.ships import GetShips
+from BreCal.impl.berths import GetBerths
+from BreCal.impl.shipcalls import GetShipcalls
+
+from BreCal.database.enums import ParticipantType
+
+def get_participant_id_dictionary():
+    """
+    get a dictionary of all participants, where the key is the participant's id, and the value is a dictionary
+    of common participant data (not a data model). 
+    """
+    # get all participants
+    response,status_code,header = GetParticipant(options={})
+
+    # build a dictionary of id:item pairs, so one can select the respective participant
+    participants = json.loads(response)
+    participants = {items.get("id"):items for items in participants}
+    return participants
+
+def get_berth_id_dictionary():
+    # get all berths
+    response,status_code,header = GetBerths(token=None)
+
+    # build a dictionary of id:item pairs, so one can select the respective participant
+    berths = json.loads(response)
+    berths = {items.get("id"):items for items in berths}
+    return berths
+
+def get_ship_id_dictionary():
+    # get all ships
+    response,status_code,header = GetShips(token=None)
+
+    # build a dictionary of id:item pairs, so one can select the respective participant
+    ships = json.loads(response)
+    ships = {items.get("id"):items for items in ships}
+    return ships
+
+def get_shipcall_id_dictionary():
+    # get all ships
+    response,status_code,header = GetShipcalls(options={'past_days':30000})
+
+    # build a dictionary of id:item pairs, so one can select the respective participant
+    shipcalls = json.loads(response)
+    shipcalls = {items.get("id"):items for items in shipcalls}
+    return shipcalls
+
+
+def get_participant_type_from_user_data(user_data:dict)->ParticipantType:
+    # user_data = decode token
+    participant_id = user_data.get("participant_id")
+
+    # build a dictionary of id:item pairs, so one can select the respective participant
+    participants = get_participant_id_dictionary()
+    participant = participants.get(participant_id,{})
+    participant_type = ParticipantType(participant.get("type",0))
+    return participant_type
+
+def check_if_user_is_bsmd_type(user_data:dict)->bool:
+    """
+    given a dictionary of user data, determine the respective participant id and read, whether
+    that participant is a .BSMD-type
+
+    Note: ParticipantType is an IntFlag. 
+        Hence, ParticipantType(1) is ParticipantType.BSMD,
+        and ParticipantType(7) is [ParticipantType.BSMD, ParticipantType.TERMINAL, ParticipantType.PILOT]
+
+        both would return 'True'
+
+    returns: boolean. Whether the participant id is a .BSMD type element
+    """
+    # use the decoded JWT token and extract the participant type
+    participant_type = get_participant_type_from_user_data(user_data)
+
+    # boolean check: is the participant of type .BSMD?
+    is_bsmd = ParticipantType.BSMD in participant_type 
+    return is_bsmd
+
+
+def check_if_ship_id_is_valid(ship_id):
+    """check, whether the provided ID is valid. If it is 'None', it will be considered valid. This is, because a shipcall POST-request, does not have to include all IDs at once"""
+    if ship_id is None:
+        return True
+    
+    # build a dictionary of id:item pairs, so one can select the respective participant
+    ships = get_ship_id_dictionary()
+    
+    # boolean check
+    ship_id_is_valid = ship_id in list(ships.keys())
+    return ship_id_is_valid
+
+def check_if_berth_id_is_valid(berth_id):
+    """check, whether the provided ID is valid. If it is 'None', it will be considered valid. This is, because a shipcall POST-request, does not have to include all IDs at once"""
+    if berth_id is None:
+        return True
+    
+    # build a dictionary of id:item pairs, so one can select the respective participant
+    berths = get_berth_id_dictionary()
+
+    # boolean check
+    berth_id_is_valid = berth_id in list(berths.keys())
+    return berth_id_is_valid
+
+def check_if_shipcall_id_is_valid(shipcall_id:int):
+    """check, whether the provided ID is valid. If it is 'None', it will be considered valid. This is, because a request, may not have to include all IDs at once"""
+    if shipcall_id is None:
+        return True
+    
+    # build a dictionary of id:item pairs, so one can select the respective participant
+    shipcalls = get_shipcall_id_dictionary()
+
+    # boolean check
+    shipcall_id_is_valid = shipcall_id in list(shipcalls.keys())
+    return shipcall_id_is_valid
+
+def check_if_participant_id_is_valid_standalone(participant_id:int):
+    """check, whether the provided ID is valid. If it is 'None', it will be considered valid. This is, because a request, may not have to include all IDs at once"""
+    if participant_id is None:
+        return True
+    
+    # build a dictionary of id:item pairs, so one can select the respective participant
+    participants = get_participant_id_dictionary()
+
+    # boolean check
+    participant_id_is_valid = participant_id in list(participants.keys())
+    return participant_id_is_valid
+
+def check_if_participant_id_is_valid(participant:dict):
+    """
+    check, whether the provided ID is valid. If it is 'None', it will be considered valid. This is, because a shipcall POST-request, does not have to include all IDs at once
+    
+    Following the common BreCal.schemas.model.ParticipantAssignmentSchema, a participant dictionary contains the keys:
+        'participant_id' : int
+        'type' : ParticipantType
+    """
+    # #TODO1: Daniel Schick: 'types may only appear once and must not include type "BSMD"'
+    participant_id = participant.get("participant_id", None)
+    participant_id_is_valid = check_if_participant_id_is_valid_standalone(participant_id)
+    return participant_id_is_valid
+
+def check_if_participant_ids_are_valid(participants:list[dict]):
+    """
+
+    args:
+        participants (list of participant-elements)
+            Following the common BreCal.schemas.model.ParticipantAssignmentSchema, a participant dictionary contains the keys:
+                'participant_id' : int
+                'type' : ParticipantType
+    """
+    # empty list -> invalid
+    if participants is None:
+        return False
+    
+    # check each participant id individually
+    valid_participant_ids = [check_if_participant_id_is_valid(participant) for participant in participants]
+
+    # boolean check, whether all participant ids are valid
+    return all(valid_participant_ids)
+
+def check_if_participant_ids_and_types_are_valid(participants:list[dict[str,int]]):
+    # creates a Counter object, which counts the number of unique elements
+    # key of counter: type, value of counter: number of listings in 'participants'
+    # e.g., {1: 4, 2: 1, 8: 1} (type 1 occurs 4 times in this example)
+    counter_type = Counter([participant.get("type") for participant in participants])
+    counter_id = Counter([participant.get("type") for participant in participants])
+
+    # obtains the maximum count from the counter's values
+    max_count_type = max(list(counter_type.values())) if len(list(counter_type.values()))>0 else 0
+    max_count_ids = max(list(counter_id.values())) if len(list(counter_id.values()))>0 else 0
+
+    # when 0 or 1 count for the participant ids or types, return true. Return false, when there is more than one entry.
+    return max_count_type <= 1 and max_count_ids <= 1
+
+
+
+
+
+
diff --git a/src/server/BreCal/validators/time_logic.py b/src/server/BreCal/validators/time_logic.py
index 3c096a1..8ebad56 100644
--- a/src/server/BreCal/validators/time_logic.py
+++ b/src/server/BreCal/validators/time_logic.py
@@ -2,6 +2,8 @@ import datetime
 import numpy as np
 import pandas as pd
 
+from marshmallow import ValidationError
+
 def validate_time_exceeds_threshold(value:datetime.datetime, seconds:int=60, minutes:int=60, hours:int=24, days:int=30, months:int=12)->bool:
     """returns a boolean when the input value is very distant in the future. The parameters provide the threshold"""
     # time difference in seconds. Positive: in the future, Negative: in the past
@@ -10,6 +12,37 @@ def validate_time_exceeds_threshold(value:datetime.datetime, seconds:int=60, min
     threshold = seconds*minutes*hours*days*months
     return time_>=threshold
 
+def validate_time_is_in_future(value:datetime.datetime):
+    """returns a boolean when the input value is in the future."""
+    current_time = datetime.datetime.now()
+    return value >= current_time
+
+def validate_time_is_in_not_too_distant_future(raise_validation_error:bool, value:datetime.datetime, seconds:int=60, minutes:int=60, hours:int=24, days:int=30, months:int=12)->bool:
+    """
+    combines two boolean operations. Returns True when both conditions are met.
+        a) value is in the future
+        b) value is not too distant (e.g., at max. 1 year in the future)
+
+    When the value is 'None', the validation will be skipped. A ValidationError is never issued, but the method returns 'False'.
+
+    options:
+        raise_validation_error: boolean. If set to True, this method issues a marshmallow.ValidationError, when the conditions fail.
+    """
+    if value is None:
+        return False
+    
+    is_in_future = validate_time_is_in_future(value)
+    is_too_distant = validate_time_exceeds_threshold(value, seconds, minutes, hours, days, months)
+
+    if raise_validation_error:
+        if not is_in_future:
+            raise ValidationError(f"The provided value must be in the future. Current Time: {datetime.datetime.now()}, Value: {value}")
+        
+        if is_too_distant:
+            raise ValidationError(f"The provided value is in the too distant future and exceeds a threshold for 'reasonable' entries. Found: {value}")
+        
+    return is_in_future & (not is_too_distant)
+
 class TimeLogic():
     def __init__(self):
         return
diff --git a/src/server/BreCal/validators/validation_base_utils.py b/src/server/BreCal/validators/validation_base_utils.py
new file mode 100644
index 0000000..82ced1f
--- /dev/null
+++ b/src/server/BreCal/validators/validation_base_utils.py
@@ -0,0 +1,20 @@
+from string import ascii_letters, digits
+
+
+def check_if_string_has_special_characters(text:str):
+    """
+    check, whether there are any characters within the provided string, which are not found in the ascii letters or digits
+        ascii_letters: abcd (...) and ABCD (...)
+        digits: 0123 (...)
+
+    Source: https://stackoverflow.com/questions/57062794/is-there-a-way-to-check-if-a-string-contains-special-characters
+    User: https://stackoverflow.com/users/10035985/andrej-kesely
+    returns bool
+    """
+    return bool(set(text).difference(ascii_letters + digits))
+
+
+def check_if_int_is_valid_flag(value, enum_object):
+    # e.g., when an IntFlag has the values 1,2,4; the maximum valid value is 7
+    max_int = sum([int(val) for val in list(enum_object._value2member_map_.values())])
+    return 0 < value <= max_int
\ No newline at end of file
diff --git a/src/server/BreCal/validators/validation_rule_functions.py b/src/server/BreCal/validators/validation_rule_functions.py
index 98fff6e..24bbc62 100644
--- a/src/server/BreCal/validators/validation_rule_functions.py
+++ b/src/server/BreCal/validators/validation_rule_functions.py
@@ -38,14 +38,16 @@ error_message_dict = {
     "validation_rule_fct_etd_time_not_in_tidal_window":"The tidal window does not fit to the agency's estimated time of departure (ETD) {Rule #0004B}",
 
     # 0005 A+B
-    "validation_rule_fct_too_many_identical_eta_times":"There are more than three ships with the same planned time of arrival (ETA) {Rule #0005A}",
-    "validation_rule_fct_too_many_identical_etd_times":"There are more than three ships with the same planned time of departure (ETD) {Rule #0005B}",
+    "validation_rule_fct_too_many_identical_eta_times":"More than three shipcalls are planned at the same time as the defined ETA {Rule #0005A}",
+    "validation_rule_fct_too_many_identical_etd_times":"More than three shipcalls are planned at the same time as the defined ETD {Rule #0005B}",
 
     # 0006 A+B
     "validation_rule_fct_agency_and_terminal_berth_id_disagreement":"Agency and Terminal are planning with different berths (the berth_id deviates). {Rule #0006A}",
     "validation_rule_fct_agency_and_terminal_pier_side_disagreement":"Agency and Terminal are planning with different pier sides (the pier_side deviates).  {Rule #0006B}",
 }
 
+
+
 class ValidationRuleBaseFunctions():
     """
     Base object with individual functions, which the {ValidationRuleFunctions}-child refers to.
@@ -71,6 +73,18 @@ class ValidationRuleBaseFunctions():
     def get_no_violation_default_output(self):
         """return the default output of a validation function with no validation: a tuple of (GREEN state, None)"""
         return (StatusFlags.GREEN, None)
+        
+    def check_if_header_exists(self, df_times:pd.DataFrame, participant_type:ParticipantType)->bool:
+        """
+        Given a pandas DataFrame, which contains times entries for a specific shipcall id,
+        this function checks, whether one of the times entries belongs to the requested ParticipantType.
+
+        returns bool
+        """
+        # empty DataFrames form a special case, as they might miss the 'participant_type' column.
+        if len(df_times)==0:
+            return False
+        return participant_type in df_times.loc[:,"participant_type"].values
 
     def check_time_delta_violation_query_time_to_now(self, query_time:pd.Timestamp, key_time:pd.Timestamp, threshold:float)->bool:
         """
@@ -144,7 +158,6 @@ class ValidationRuleBaseFunctions():
             return violation_state
 
         df_times = df_times.loc[df_times["participant_type"].isin(participant_types),:]
-        agency_time = [time_ for time_ in agency_times.loc[:,query].tolist() if isinstance(time_, pd.Timestamp)]
 
         # for the given query, e.g., 'eta_berth', sample all times from the pandas DataFrame
         # exclude missing entries and consider only pd.Timestamp entries (which ignores pd.NaT/null entries)
@@ -172,6 +185,7 @@ class ValidationRuleBaseFunctions():
         violation_state = any(time_difference_exceeds_threshold)
 
         # this (previous) solution compares times to the reference (agency) time and checks if the difference is greater than 15 minutes
+        # agency_time = [time_ for time_ in agency_times.loc[:,query].tolist() if isinstance(time_, pd.Timestamp)]
         # violation_state = ((np.max(estimated_times) - agency_time[0]) > pd.Timedelta("15min")) or ((agency_time[0] - np.min(estimated_times)) > pd.Timedelta("15min"))
 
         # this solution to the rule compares all times to each other. When there is a total difference of more than 15 minutes, a violation occurs
@@ -762,10 +776,12 @@ class ValidationRuleFunctions(ValidationRuleBaseFunctions):
             return self.get_no_violation_default_output()
 
         # check, if the header is filled in (agency & terminal)
-        if len(df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value]) != 1:
+        if not self.check_if_header_exists(df_times, participant_type=ParticipantType.AGENCY):
+        # if len(df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value]) != 1:
             return self.get_no_violation_default_output() # rule not applicable
 
-        if len(df_times.loc[df_times["participant_type"]==ParticipantType.TERMINAL.value]) != 1:
+        if not self.check_if_header_exists(df_times, participant_type=ParticipantType.TERMINAL):
+        #if len(df_times.loc[df_times["participant_type"]==ParticipantType.TERMINAL.value]) != 1:
             return self.get_no_violation_default_output() # rule not applicable
 
         # get agency & terminal times
@@ -805,10 +821,12 @@ class ValidationRuleFunctions(ValidationRuleBaseFunctions):
             return self.get_no_violation_default_output()
 
         # check, if the header is filled in (agency & terminal)
-        if len(df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value]) != 1:
+        # if len(df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value]) != 1:
+        if not self.check_if_header_exists(df_times, participant_type=ParticipantType.AGENCY):
             return self.get_no_violation_default_output() # rule not applicable
 
-        if len(df_times.loc[df_times["participant_type"]==ParticipantType.TERMINAL.value]) != 1:
+        # if len(df_times.loc[df_times["participant_type"]==ParticipantType.TERMINAL.value]) != 1:
+        if not self.check_if_header_exists(df_times, participant_type=ParticipantType.TERMINAL):
             return self.get_no_violation_default_output() # rule not applicable
 
         # get agency & terminal times
@@ -845,7 +863,8 @@ class ValidationRuleFunctions(ValidationRuleBaseFunctions):
             return self.get_no_violation_default_output()
 
         # check, if the header is filled in (agency)
-        if len(df_times.loc[df_times["participant_type"].isin([ParticipantType.AGENCY.value])]) != 1:
+        # if len(df_times.loc[df_times["participant_type"].isin([ParticipantType.AGENCY.value])]) != 1:
+        if not self.check_if_header_exists(df_times, participant_type=ParticipantType.AGENCY):
             return self.get_no_violation_default_output()
         times_agency = self.sql_handler.get_times_for_participant_type(df_times, participant_type=ParticipantType.AGENCY.value)
 
@@ -876,7 +895,8 @@ class ValidationRuleFunctions(ValidationRuleBaseFunctions):
             return self.get_no_violation_default_output()
 
         # check, if the header is filled in (agency)
-        if len(df_times.loc[df_times["participant_type"].isin([ParticipantType.AGENCY.value])]) != 1:
+        # if len(df_times.loc[df_times["participant_type"].isin([ParticipantType.AGENCY.value])]) != 1:
+        if not self.check_if_header_exists(df_times, participant_type=ParticipantType.AGENCY):
             return self.get_no_violation_default_output()
         times_agency = self.sql_handler.get_times_for_participant_type(df_times, participant_type=ParticipantType.AGENCY.value)
 
@@ -898,16 +918,19 @@ class ValidationRuleFunctions(ValidationRuleBaseFunctions):
         """
         Code: #0005-A
         Type: Global Rule
-        Description: this validation rule checks, whether there are too many shipcalls with identical ETA times.
+        Description: this validation rule checks, whether there are too many shipcalls with identical times to the query ETA.
         """
-        times_agency = df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value]
         # check, if the header is filled in (agency)
-        if len(times_agency) != 1:
+        if not self.check_if_header_exists(df_times, participant_type=ParticipantType.AGENCY): # if len(times_agency) != 1:
             return self.get_no_violation_default_output()
 
-        # when ANY of the unique values exceeds the threshold, a violation is observed
-        query = "eta_berth"
-        violation_state = self.check_unique_shipcall_counts(query, times_agency=times_agency, rounding=rounding, maximum_threshold=maximum_threshold, all_times_agency=all_times_agency)
+        # get the agency's query time
+        times_agency = df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value]
+        query_time = times_agency.iloc[0].eta_berth
+
+        # count the number of times, where a times entry is very close to the query time (uses an internal threshold, such as 15 minutes)
+        counts = self.sql_handler.count_synchronous_shipcall_times(query_time, all_df_times=all_times_agency)
+        violation_state = counts > maximum_threshold
 
         if violation_state:
             validation_name = "validation_rule_fct_too_many_identical_eta_times"
@@ -919,16 +942,19 @@ class ValidationRuleFunctions(ValidationRuleBaseFunctions):
         """
         Code: #0005-B
         Type: Global Rule
-        Description: this validation rule checks, whether there are too many shipcalls with identical ETD times.
+        Description: this validation rule checks, whether there are too many shipcalls with identical times to the query ETD.
         """
-        times_agency = df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value]
         # check, if the header is filled in (agency)
-        if len(times_agency) != 1:
+        if not self.check_if_header_exists(df_times, participant_type=ParticipantType.AGENCY): #if len(times_agency) != 1:
             return self.get_no_violation_default_output()
 
-        # when ANY of the unique values exceeds the threshold, a violation is observed
-        query = "etd_berth"
-        violation_state = self.check_unique_shipcall_counts(query, times_agency=times_agency, rounding=rounding, maximum_threshold=maximum_threshold, all_times_agency=all_times_agency)
+        # get the agency's query time
+        times_agency = df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value]
+        query_time = times_agency.iloc[0].etd_berth
+
+        # count the number of times, where a times entry is very close to the query time (uses an internal threshold, such as 15 minutes)
+        counts = self.sql_handler.count_synchronous_shipcall_times(query_time, all_df_times=all_times_agency)
+        violation_state = counts > maximum_threshold
 
         if violation_state:
             validation_name = "validation_rule_fct_too_many_identical_etd_times"
@@ -943,10 +969,12 @@ class ValidationRuleFunctions(ValidationRuleBaseFunctions):
         Description: This validation rule checks, whether agency and terminal agree with their designated berth place by checking berth_id.
         """
         # check, if the header is filled in (agency & terminal)
-        if len(df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value]) == 0:
+        # if len(df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value]) == 0:
+        if not self.check_if_header_exists(df_times, participant_type=ParticipantType.AGENCY):
             return self.get_no_violation_default_output() # rule not applicable
 
-        if len(df_times.loc[df_times["participant_type"]==ParticipantType.TERMINAL.value]) == 0:
+        # if len(df_times.loc[df_times["participant_type"]==ParticipantType.TERMINAL.value]) == 0:
+        if not self.check_if_header_exists(df_times, participant_type=ParticipantType.TERMINAL):
             return self.get_no_violation_default_output() # rule not applicable
 
         times_agency = self.sql_handler.get_times_for_participant_type(df_times, participant_type=ParticipantType.AGENCY.value)
@@ -979,13 +1007,14 @@ class ValidationRuleFunctions(ValidationRuleBaseFunctions):
         Description: This validation rule checks, whether agency and terminal agree with their designated pier side by checking pier_side.
         """
         # check, if the header is filled in (agency & terminal)
-        if len(df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value]) == 0:
+        # if len(df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value]) == 0:
+        if not self.check_if_header_exists(df_times, participant_type=ParticipantType.AGENCY):
             return self.get_no_violation_default_output() # rule not applicable
 
-        if len(df_times.loc[df_times["participant_type"]==ParticipantType.TERMINAL.value]) == 0:
+        # if len(df_times.loc[df_times["participant_type"]==ParticipantType.TERMINAL.value]) == 0:
+        if not self.check_if_header_exists(df_times, participant_type=ParticipantType.TERMINAL):
             return self.get_no_violation_default_output() # rule not applicable
 
-        times_agency = self.sql_handler.get_times_for_participant_type(df_times, participant_type=ParticipantType.AGENCY.value)
         times_terminal = self.sql_handler.get_times_for_participant_type(df_times, participant_type=ParticipantType.TERMINAL.value)
 
         # when one of the two values is null, the state is GREEN
diff --git a/src/server/BreCal/validators/validation_rules.py b/src/server/BreCal/validators/validation_rules.py
index 405b0b6..03ffc1f 100644
--- a/src/server/BreCal/validators/validation_rules.py
+++ b/src/server/BreCal/validators/validation_rules.py
@@ -3,6 +3,7 @@ import logging
 import re
 import numpy as np
 import pandas as pd
+import datetime
 from BreCal.database.enums import StatusFlags
 from BreCal.validators.validation_rule_functions import ValidationRuleFunctions
 from BreCal.schemas.model import Shipcall
@@ -17,10 +18,6 @@ class ValidationRules(ValidationRuleFunctions):
     """
     def __init__(self, sql_handler): # use the entire data that is provided for this query (e.g., json input)
         super().__init__(sql_handler)
-
-        self.validation_state = self.determine_validation_state()
-        # currently flagged: notification_state initially was based on using one ValidationRules object for each query. This is deprecated.
-        # self.notification_state = self.determine_notification_state() # (state:str, should_notify:bool)
         return
 
     def evaluate(self, shipcall):
@@ -31,9 +28,9 @@ class ValidationRules(ValidationRuleFunctions):
         returns: (evaluation_state, violations)
         """
         # prepare df_times, which every validation rule tends to use
-        df_times = self.sql_handler.df_dict.get('times', pd.DataFrame()) # -> pd.DataFrame
+        all_df_times = self.sql_handler.df_dict.get('times', pd.DataFrame()) # -> pd.DataFrame
 
-        if len(df_times)==0:
+        if len(all_df_times)==0:
             return (StatusFlags.GREEN.value, [])
 
         spm = self.sql_handler.df_dict["shipcall_participant_map"]
@@ -74,16 +71,26 @@ class ValidationRules(ValidationRuleFunctions):
         return evaluation_state, violations
 
     def evaluate_shipcalls(self, shipcall_df:pd.DataFrame)->pd.DataFrame:
-        """apply 'evaluate_shipcall_from_df' to each individual shipcall in {shipcall_df}. Returns shipcall_df ('evaluation' and 'evaluation_message' are updated)"""
-        results = shipcall_df.apply(lambda x: self.evaluate_shipcall_from_df(x), axis=1).values
+        """apply 'evaluate_shipcall_from_df' to each individual shipcall in {shipcall_df}. Returns shipcall_df ('evaluation', 'evaluation_message', 'evaluation_time' and 'evaluation_notifications_sent' are updated)"""
+        evaluation_states_old = [state_old for state_old in shipcall_df.loc[:,"evaluation"]]
+        evaluation_states_old = [state_old if not pd.isna(state_old) else 0 for state_old in evaluation_states_old]
+        results = shipcall_df.apply(lambda x: self.evaluate_shipcall_from_df(x), axis=1).values # returns tuple (state, message)
 
-        # unbundle individual results. evaluation_state becomes an integer, violation
-        evaluation_state = [StatusFlags(res[0]).value for res in results]
+        # unbundle individual results. evaluation_states becomes an integer, violation 
+        evaluation_states_new = [StatusFlags(res[0]).value for res in results]
         violations = [",\r\n".join(res[1]) if len(res[1])>0 else None for res in results]
         violations = [self.concise_evaluation_message_if_too_long(violation) for violation in violations]
 
-        shipcall_df.loc[:,"evaluation"] = evaluation_state
+        # build the list of evaluation times ('now', as isoformat)
+        #evaluation_time = self.get_notification_times(evaluation_states_new)
+
+        # build the list of 'evaluation_notifications_sent'. The value is 'False', when a notification should be created
+        #evaluation_notifications_sent = self.get_notification_states(evaluation_states_old, evaluation_states_new)
+
+        shipcall_df.loc[:,"evaluation"] = evaluation_states_new
         shipcall_df.loc[:,"evaluation_message"] = violations
+        #shipcall_df.loc[:,"evaluation_time"] = evaluation_time
+        #shipcall_df.loc[:,"evaluation_notifications_sent"] = evaluation_notifications_sent
         return shipcall_df
 
     def concise_evaluation_message_if_too_long(self, violation):
@@ -100,36 +107,27 @@ class ValidationRules(ValidationRuleFunctions):
             # e.g.: Evaluation message too long. Violated Rules: ['Rule #0001C', 'Rule #0001H', 'Rule #0001F', 'Rule #0001G', 'Rule #0001L', 'Rule #0001M', 'Rule #0001J', 'Rule #0001K']
             violation = f"Evaluation message too long. Violated Rules: {concise}"
         return violation
-
-    def determine_validation_state(self) -> str:
+        
+    def undefined_method(self) -> str:
+        """this function should apply the ValidationRules to the respective .shipcall, in regards to .times"""
+        return (StatusFlags.GREEN, False) # (state:str, should_notify:bool)
+    
+    def determine_notification_state(self, state_old, state_new):
         """
-        this method determines the validation state of a shipcall. The state is either ['green', 'yellow', 'red'] and signals,
-        whether an entry causes issues within the workflow of users.
-
-        returns: validation_state_new (str)
+        this method determines state changes in the notification state. When the state increases, a user is notified about it. 
+        state order: (NONE = GREEN < YELLOW < RED)
         """
-        (validation_state_new, description) = self.undefined_method()
-        # should there also be notifications for critical validation states? In principle, the traffic light itself provides that notification.
-        self.validation_state = validation_state_new
-        return validation_state_new
+        # identify a state increase
+        should_notify = self.identify_notification_state_change(state_old=state_old, state_new=state_new)
 
-    def determine_notification_state(self) -> (str, bool):
+        # when a state increases, a notification must be sent. Thereby, the field should be set to False ({evaluation_notifications_sent})
+        evaluation_notifications_sent = False if bool(should_notify) else None
+        return evaluation_notifications_sent
+    
+    def identify_notification_state_change(self, state_old, state_new) -> bool:
         """
-        this method determines state changes in the notification state. When the state is changed to yellow or red,
-        a user is notified about it. The only exception for this rule is when the state was yellow or red before,
-        as the user has then already been notified.
-
-        returns: notification_state_new (str), should_notify (bool)
-        """
-        (state_new, description) = self.undefined_method() # determine the successor
-        should_notify = self.identify_notification_state_change(state_new)
-        self.notification_state = state_new # overwrite the predecessor
-        return state_new, should_notify
-
-    def identify_notification_state_change(self, state_new) -> bool:
-        """
-        determines, whether the observed state change should trigger a notification.
-        internally, this function maps a color string to an integer and determines, if the successor state is more severe than the predecessor.
+        determines, whether the observed state change should trigger a notification. 
+        internally, this function maps StatusFlags to an integer and determines, if the successor state is more severe than the predecessor.
 
         state changes trigger a notification in the following cases:
             green -> yellow
@@ -138,15 +136,46 @@ class ValidationRules(ValidationRuleFunctions):
 
             (none -> yellow) or (none -> red)
             due to the values in the enumeration objects, the states are mapped to provide this function.
-            green=1, yellow=2, red=3, none=1. Hence, critical changes can be observed by simply checking with "greater than".
+            green=1, yellow=2, red=3, none=1. Hence, critical changes can be observed by simply checking with "greater than". 
 
         returns bool, whether a notification should be triggered
         """
         # state_old is always considered at least 'Green' (1)
-        state_old = max(copy.copy(self.notification_state) if "notification_state" in list(self.__dict__.keys()) else StatusFlags.NONE, StatusFlags.GREEN.value)
-        return state_new.value > state_old.value
+        if state_old is None:
+            state_old = StatusFlags.NONE.value
+        state_old = max(int(state_old), StatusFlags.GREEN.value)
+        return int(state_new) > int(state_old)
+    
+    def get_notification_times(self, evaluation_states_new)->list[datetime.datetime]:
+        """# build the list of evaluation times ('now', as isoformat)"""
+        evaluation_times = [datetime.datetime.now().isoformat() for _i in range(len(evaluation_states_new))]
+        return evaluation_times
+    
+    def get_notification_states(self, evaluation_states_old, evaluation_states_new)->list[bool]:
+        """# build the list of 'evaluation_notifications_sent'. The value is 'False', when a notification should be created"""
+        evaluation_notifications_sent = [self.determine_notification_state(state_old=int(state_old), state_new=int(state_new)) for state_old, state_new in zip(evaluation_states_old, evaluation_states_new)]
+        return evaluation_notifications_sent
 
-    def undefined_method(self) -> str:
-        """this function should apply the ValidationRules to the respective .shipcall, in regards to .times"""
-        # #TODO_traffic_state
-        return (StatusFlags.GREEN, False) # (state:str, should_notify:bool)
+
+def inspect_shipcall_evaluation(vr, sql_handler, shipcall_id):
+    """
+    # debug only!
+    
+    a simple debugging function, which serves in inspecting an evaluation function for a single shipcall id. It returns the result and all related data.
+    returns: result, shipcall_df (filtered by shipcall id), shipcall, spm (shipcall participant map, filtered by shipcall id), times_df (filtered by shipcall id)
+    """
+    shipcall_df = sql_handler.df_dict.get("shipcall").loc[shipcall_id:shipcall_id,:]
+
+    shipcall = Shipcall(**{**{"id":shipcall_id},**sql_handler.df_dict.get("shipcall").loc[shipcall_id].to_dict()})
+    result = vr.evaluate(shipcall=shipcall)
+    notification_state = vr.identify_notification_state_change(state_old=int(shipcall.evaluation), state_new=int(result[0]))
+    print(f"Previous state: {int(shipcall.evaluation)}, New State: {result[0]}, Notification State: {notification_state}")
+        
+    times_df = sql_handler.df_dict.get("times")
+    times_df = times_df.loc[times_df["shipcall_id"]==shipcall_id]
+
+
+    spm = sql_handler.df_dict["shipcall_participant_map"]
+    spm = spm.loc[spm["shipcall_id"]==shipcall_id]
+
+    return result, shipcall_df, shipcall, spm, times_df
diff --git a/src/server/tests/database/__init__.py b/src/server/tests/database/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/src/server/tests/database/test_sql_queries.py b/src/server/tests/database/test_sql_queries.py
new file mode 100644
index 0000000..88e546d
--- /dev/null
+++ b/src/server/tests/database/test_sql_queries.py
@@ -0,0 +1,527 @@
+import pytest
+
+import os
+import bcrypt
+import pydapper
+from BreCal import local_db
+from BreCal.database.sql_handler import execute_sql_query_standalone
+from BreCal.database.sql_queries import SQLQuery
+from BreCal.schemas import model
+from BreCal.stubs.user import get_user_simple
+
+instance_path = os.path.join(os.path.expanduser('~'), "brecal", "src", "server", "instance", "instance")
+local_db.initPool(os.path.dirname(instance_path), connection_filename="connection_data_local.json")
+
+def test_sql_query_every_call_returns_str():
+    assert isinstance(SQLQuery.get_berth(), str)
+    return
+
+def test_sql_query_get_berths():
+    schemas = execute_sql_query_standalone(query=SQLQuery.get_berth(), param={})
+    berths = [model.Berth(**schema) for schema in schemas]
+    assert all([isinstance(berth, model.Berth) for berth in berths]), f"one of the returned schemas is not a Berth object"
+    return
+
+def test_sql_query_get_history():
+    options = {"shipcall_id":157}
+    history = execute_sql_query_standalone(query=SQLQuery.get_history(), param={"shipcallid" : options["shipcall_id"]}, model=model.History.from_query_row)
+    assert all([isinstance(hist,model.History) for hist in history])
+    return
+
+def test_sql_query_get_user():
+    options = {"username":"maxm"}
+    users = execute_sql_query_standalone(query=SQLQuery.get_user(), param={"username" : options["username"]}, model=model.User)
+    assert all([isinstance(user,model.User) for user in users])
+    assert users[0].user_name==options["username"]
+    return
+
+def test_sql_get_notifications():
+    import mysql.connector
+
+    # unfortunately, there currently is *no* notification in the database. 
+    with pytest.raises(mysql.connector.errors.ProgrammingError, match="Unknown column 'shipcall_id' in 'field list'"):
+        options = {"shipcall_id":417}
+        notifications = execute_sql_query_standalone(query=SQLQuery.get_notifications(), param={"scid" : options["shipcall_id"]}, model=model.Notification.from_query_row)
+        assert all([isinstance(notification,model.Notification) for notification in notifications])
+    return
+
+def test_sql_get_participants():
+    participants = execute_sql_query_standalone(query=SQLQuery.get_participants(), param={}, model=model.Participant)
+    assert all([isinstance(participant,model.Participant) for participant in participants])
+    return
+
+def test_sql_get_participants():
+    options = {"user_id":29}
+    query = SQLQuery.get_participant_by_user_id()
+    participants = execute_sql_query_standalone(query=query, param={"userid" : options["user_id"]}, model=model.Participant)
+    assert all([isinstance(participant,model.Participant) for participant in participants])
+    assert len(participants)==1, f"there should only be one match for the respective user id"
+    assert participants[0].id == 136, f"user 29 belongs to participant_id 136"
+    return
+
+def test_sql_get_shipcalls():
+    from BreCal.database.sql_queries import create_sql_query_shipcall_get
+
+    # different styles for the same outcome
+    options = {"past_days":3000}
+    query = create_sql_query_shipcall_get(options)
+    shipcalls = execute_sql_query_standalone(query=query, param=options, model=model.Shipcall.from_query_row)
+    assert all([isinstance(shipcall,model.Shipcall) for shipcall in shipcalls])
+
+    query = SQLQuery.get_shipcalls() # defaults to 'past_days'=3
+    shipcalls = execute_sql_query_standalone(query=query, param=options, model=model.Shipcall.from_query_row)
+    assert all([isinstance(shipcall,model.Shipcall) for shipcall in shipcalls])
+
+    query = SQLQuery.get_shipcalls({'past_days':3000})
+    shipcalls = execute_sql_query_standalone(query=query, param=options, model=model.Shipcall.from_query_row)
+    assert all([isinstance(shipcall,model.Shipcall) for shipcall in shipcalls])
+
+    # fails: options must contain 'past_days' key
+    with pytest.raises(AssertionError, match="there must be a key 'past_days' in the options, which determines"):
+        query = SQLQuery.get_shipcalls(options={})
+        shipcalls = execute_sql_query_standalone(query=query, param=options, model=model.Shipcall.from_query_row)
+    return
+
+def test_sql_get_ships():
+    ships = execute_sql_query_standalone(query=SQLQuery.get_ships(), model=model.Ship)
+    assert all([isinstance(ship, model.Ship) for ship in ships])
+    return
+
+def test_sql_get_times():
+    options = {'shipcall_id':153}
+    times = execute_sql_query_standalone(query=SQLQuery.get_times(), model=model.Times, param={"scid" : options["shipcall_id"]})
+    assert all([isinstance(time_,model.Times) for time_ in times])
+    assert times[0].shipcall_id==options["shipcall_id"]
+    return
+
+def test_sql_get_user_by_id():
+    # success: id 29 exists
+    schemaModel = get_user_simple().__dict__
+    schemaModel["id"] = 29
+
+    sentinel = object()
+    query = SQLQuery.get_user_by_id()
+    pooledConnection = local_db.getPoolConnection()
+    commands = pydapper.using(pooledConnection)
+    theuser = commands.query_single_or_default(query, sentinel, param={"id" : schemaModel["id"]}, model=model.User)
+
+    if theuser is sentinel:
+        pooledConnection.close()
+
+    theuser.id == schemaModel["id"]
+    
+    # fails: id 292212 does not exist (returns default, which is the sentinel object in this case)
+    schemaModel = get_user_simple().__dict__
+    schemaModel["id"] = 292212
+
+    sentinel = object()
+    query = SQLQuery.get_user_by_id()
+    pooledConnection = local_db.getPoolConnection()
+    commands = pydapper.using(pooledConnection)
+    theuser = commands.query_single_or_default(query, sentinel, param={"id" : schemaModel["id"]}, model=model.User)
+
+    if theuser is sentinel:
+        pooledConnection.close()
+
+    assert theuser is sentinel
+    return
+
+def test_sql_get_user_put():
+    """the PUT query for a user must be built based on a schemaModel, as the available data is dynamic and the query must be adaptive."""
+    schemaModel = get_user_simple().__dict__
+    schemaModel["id"] = 29
+
+    query = "UPDATE user SET "
+    isNotFirst = False
+    for key in schemaModel.keys():
+        if key == "id":
+            continue
+        if key == "old_password":
+            continue
+        if key == "new_password":
+            continue
+        if isNotFirst:
+            query += ", "
+        isNotFirst = True
+        query += key + " = ?" + key + "? "
+
+    query += "WHERE id = ?id?"
+
+    assert SQLQuery.get_user_put(schemaModel) == query
+    return
+
+def test_sql_user_put_set_lastname_check_unset_lastname_check():
+    """
+    Simply put, this method updates the last_name of user 29 to "Metz", verifies the change,
+    and then proceeds to set it back to "Mustermann", and verifies the change. 
+    """
+    # 1.) SET the last_name of user_id 29 to 'Metz' by a PUT command
+    schemaModel = get_user_simple().__dict__
+    schemaModel["id"] = 29
+    schemaModel["last_name"] = "Metz" # -> "Metz" -> "Mustermann"
+    schemaModel = {k:v for k,v in schemaModel.items() if k in ["id", "last_name"]}
+
+    query = SQLQuery.get_user_put(schemaModel)
+    affected_rows = execute_sql_query_standalone(query=query, param=schemaModel, command_type="execute")
+    assert affected_rows==1, f"at least one row should be affected by this call."
+
+    # 2.) GET the user_id 29 and verify the last_name is 'Metz'
+    sentinel = object()
+    query = SQLQuery.get_user_by_id()
+    pooledConnection = local_db.getPoolConnection()
+    commands = pydapper.using(pooledConnection)
+    theuser = commands.query_single_or_default(query, sentinel, param={"id" : schemaModel["id"]}, model=model.User)
+    pooledConnection.close()
+    assert not theuser is sentinel, f"failed GET user query"
+    assert theuser.last_name=="Metz", f"PUT command has been unsuccessful."
+
+    # 3.) SET the last_name of user_id 29 to 'Mustermann' by a PUT command
+    schemaModel = theuser.__dict__
+    schemaModel["last_name"] = "Mustermann"
+    schemaModel = {k:v for k,v in schemaModel.items() if k in ["id", "last_name"]}
+
+    query = SQLQuery.get_user_put(schemaModel)
+    affected_rows = execute_sql_query_standalone(query=query, param=schemaModel, command_type="execute")
+    assert affected_rows==1, f"at least one row should be affected by this call."
+
+    # 4.) GET the user_id 29 and verify the last_name is 'Mustermann'
+    sentinel = object()
+    query = SQLQuery.get_user_by_id()
+    pooledConnection = local_db.getPoolConnection()
+    commands = pydapper.using(pooledConnection)
+    theuser = commands.query_single_or_default(query, sentinel, param={"id" : schemaModel["id"]}, model=model.User)
+    pooledConnection.close()
+    assert not theuser is sentinel, f"failed GET user query"
+    assert theuser.last_name=="Mustermann", f"PUT command has been unsuccessful."
+    return
+
+def test_sql_user_update_password():
+    """This test updates the default password of user 29 from 'Start1234' to 'Start4321' and afterwards sets it back to 'Start1234'."""
+    # #TODO: this test very openly displays the password of 'maxm'. It makes sense to create a stub user in the database, which can be
+    # used for these tests, so an account without any importance or valuable assigned role is insecure instead. 
+
+    # Set. Update the password of user 29 from 'Start1234' to 'Start4321'
+    schemaModel = get_user_simple().__dict__
+    schemaModel["id"] = 29
+    schemaModel["old_password"] = "Start1234"
+    schemaModel["new_password"] = "Start4321"
+
+    sentinel = object()
+    query = SQLQuery.get_user_by_id()
+    pooledConnection = local_db.getPoolConnection()
+    commands = pydapper.using(pooledConnection)
+    theuser = commands.query_single_or_default(query, sentinel, param={"id" : schemaModel["id"]}, model=model.User)
+    pooledConnection.close()
+    assert not theuser is sentinel, f"failed GET user query"
+
+    assert bcrypt.checkpw(schemaModel["old_password"].encode("utf-8"), bytes(theuser.password_hash, "utf-8")), f"old password does not match to the database entry"
+
+    password_hash = bcrypt.hashpw(schemaModel["new_password"].encode('utf-8'), bcrypt.gensalt( 12 )).decode('utf8')
+    query = SQLQuery.get_update_user_password()
+    affected_rows = execute_sql_query_standalone(query=query, param={"password_hash" : password_hash, "id" : schemaModel["id"]}, command_type="execute")
+    assert affected_rows == 1
+
+    # 2.) Revert. Set password back to the default (from 'Start4321' to 'Start1234')
+    schemaModel = get_user_simple().__dict__
+    schemaModel["id"] = 29
+    schemaModel["old_password"] = "Start4321"
+    schemaModel["new_password"] = "Start1234"
+
+    sentinel = object()
+    query = SQLQuery.get_user_by_id()
+    pooledConnection = local_db.getPoolConnection()
+    commands = pydapper.using(pooledConnection)
+    theuser = commands.query_single_or_default(query, sentinel, param={"id" : schemaModel["id"]}, model=model.User)
+    pooledConnection.close()
+    assert not theuser is sentinel, f"failed GET user query"
+
+    assert bcrypt.checkpw(schemaModel["old_password"].encode("utf-8"), bytes(theuser.password_hash, "utf-8")), f"old password does not match to the database entry"
+
+    password_hash = bcrypt.hashpw(schemaModel["new_password"].encode('utf-8'), bcrypt.gensalt( 12 )).decode('utf8')
+    query = SQLQuery.get_update_user_password()
+    affected_rows = execute_sql_query_standalone(query=query, param={"password_hash" : password_hash, "id" : schemaModel["id"]}, command_type="execute")
+    assert affected_rows == 1
+    return
+
+def test_sql_get_participants_of_shipcall_id():
+    shipcall_id = 389
+    query = SQLQuery.get_participants()
+    participants = execute_sql_query_standalone(query=query, model=dict, param={"shipcall_id" : shipcall_id})
+    assert all([part.get("participant_id") is not None for part in participants])
+    assert all([part.get("type") is not None for part in participants])
+
+    # try to convert every participant into a model.Participant_Assignment
+    participants = [
+        model.Participant_Assignment(part["participant_id"], part["type"])
+        for part in participants
+    ]
+    assert all([isinstance(part,model.Participant_Assignment) for part in participants])
+    return
+
+def test_sql_get_all_shipcalls_and_assign_participants():
+    """
+    this test reproduces the SQL query within BreCal.impl.shipcalls to make sure, that the
+    query first returns all shipcalls, and then assigns all participants of the respective shipcall to it.
+    """
+    # get all shipcalls
+    options = {'past_days':30000}
+    query = SQLQuery.get_shipcalls(options)
+    shipcalls = execute_sql_query_standalone(query=query, model=model.Shipcall.from_query_row)
+    assert all([isinstance(shipcall,model.Shipcall) for shipcall in shipcalls])
+
+    # for every shipcall, assign all of its participants to it
+    for shipcall in shipcalls:
+        participant_query = SQLQuery.get_participants()
+        participants = execute_sql_query_standalone(query=participant_query, model=dict, param={"shipcall_id" : shipcall.id})
+
+        for record in participants:
+            pa = model.Participant_Assignment(record["participant_id"], record["type"])
+            shipcall.participants.append(pa)
+
+    assert any([
+        any([isinstance(participant, model.Participant_Assignment) for participant in shipcall.participants])
+        for shipcall in shipcalls
+    ]), f"at least one of the shipcalls should have an assigned model.Participant_Assignment"
+    return
+
+def test_sqlquery_get_shipcal_post_identical_to_create_sql_query_shipcall_post():
+    from BreCal.database.sql_queries import create_sql_query_shipcall_post
+    from BreCal.stubs.shipcall import get_stub_valid_shipcall_shifting, get_stub_valid_ship_loaded_model
+
+    post_data = get_stub_valid_shipcall_shifting()
+    schemaModel = get_stub_valid_ship_loaded_model(post_data)
+    query1 = SQLQuery.get_shipcall_post(schemaModel) # refactored variant of create_sql_query_shipcall_post (more concise)
+    query2 = create_sql_query_shipcall_post(schemaModel)
+
+    assert query1==query2
+    return
+
+def test_sql_post_shipcall():
+    """issues a post-request with stub data and adds it to the database."""
+    from BreCal.database.sql_queries import create_sql_query_shipcall_post
+    from BreCal.stubs.shipcall import get_stub_valid_shipcall_shifting, get_stub_valid_ship_loaded_model
+    
+    pooledConnection = local_db.getPoolConnection()
+    try:
+        commands = pydapper.using(pooledConnection)
+
+        post_data = get_stub_valid_shipcall_shifting()
+        post_data["voyage"] = "pytestRS71" # perform tagging to identify the shipcalls created by pytests (<16 characters, no special characters).
+        schemaModel = get_stub_valid_ship_loaded_model(post_data)
+        query = SQLQuery.get_shipcall_post(schemaModel) # refactored variant of create_sql_query_shipcall_post (more concise)
+        schemas = execute_sql_query_standalone(query=query, param=schemaModel, command_type="execute", pooledConnection=pooledConnection)
+        assert schemas==1, f"unsuccessful query execution. Query: {query}"
+
+        # within the same pooledConnection, ask for the last inserted id
+        query = SQLQuery.get_shipcall_post_last_insert_id()
+        new_id = commands.execute_scalar(query)
+        assert new_id > 0, f"the new id should be unlike 0.."
+
+        # add participant assignments if we have a list of participants
+        if 'participants' in schemaModel:
+            pquery = SQLQuery.get_shipcall_post_update_shipcall_participant_map()
+            for participant_assignment in schemaModel["participants"]:
+                schemas = execute_sql_query_standalone(query=pquery, param={"shipcall_id" : new_id, "participant_id" : participant_assignment["participant_id"], "type" : participant_assignment["type"]}, command_type="execute", pooledConnection=pooledConnection)
+
+
+        from BreCal.stubs.user import get_user_simple
+        # assign an artificial user with id 29 (maxm) & participant type 136
+        user_data = get_user_simple().__dict__
+        user_data["id"] = 29
+        user_data["participant_id"] = 136
+
+        # POST in the history
+        query = SQLQuery.create_sql_query_history_post()
+        schemas = execute_sql_query_standalone(query=query, param={"scid" : new_id, "pid" : user_data["participant_id"], "uid" : user_data["id"]}, command_type="execute", pooledConnection=pooledConnection)
+        assert schemas == 1, f"unsuccessful history POST"
+
+
+    finally:
+        pooledConnection.close()
+    return
+
+def test_sql_create_history_post_matches_legacy_function():
+    from BreCal.database.sql_queries import create_sql_query_history_post
+
+    query_refactored = SQLQuery.create_sql_query_history_post()
+    query_legacy = create_sql_query_history_post()
+    assert isinstance(query_refactored,str)
+    assert query_refactored==query_legacy, f"the refactored code to generate the query must be absolutely identical to the legacy version"
+    return
+
+def test_sql_get_shipcall_by_id():
+    schemaModel = {"id":63}
+
+    sentinel = object()
+    query = SQLQuery.get_shipcall_by_id()
+    pooledConnection = local_db.getPoolConnection()
+    commands = pydapper.using(pooledConnection)
+    theshipcall = commands.query_single_or_default(query, sentinel, param={"id" : schemaModel["id"]}, model=model.Shipcall)
+    pooledConnection.close()
+    assert not theshipcall is sentinel, f"failed GET user query"
+    assert theshipcall.id==schemaModel["id"]
+    return
+
+def test_sql_get_shipcall_by_id_short_version():
+    schemaModel = {"id":63}
+
+    # when model is defined, returns the data model
+    query = SQLQuery.get_shipcall_by_id()
+    schemas = execute_sql_query_standalone(query=query, param={"id" : schemaModel["id"]}, model=model.Shipcall, command_type="single")
+
+    assert schemas.id==schemaModel["id"]
+    assert isinstance(schemas, model.Shipcall)
+
+    # when model = None, returns a dictionary
+    query = SQLQuery.get_shipcall_by_id()
+    schemas = execute_sql_query_standalone(query=query, param={"id" : schemaModel["id"]}, command_type="single")
+    assert isinstance(schemas, dict)
+    assert schemas.get("id")==schemaModel["id"]
+    return
+
+def test_sql_get_shipcall_put_refactored_equals_extended_version():
+    from BreCal.database.sql_queries import create_sql_query_shipcall_put
+    from BreCal.stubs.shipcall import get_stub_valid_shipcall_shifting, get_stub_valid_ship_loaded_model
+
+    post_data = get_stub_valid_shipcall_shifting()
+    post_data["voyage"] = "pytestRS71" # perform tagging to identify the shipcalls created by pytests (<16 characters, no special characters).
+    schemaModel = get_stub_valid_ship_loaded_model(post_data)
+
+    legacy_query = create_sql_query_shipcall_put(schemaModel)
+    refactored_query = SQLQuery.get_shipcall_put(schemaModel)
+
+    assert refactored_query == legacy_query, f"version conflict. the refactored query must precisely match the legacy query!"
+    return
+
+def test_sql_get_shipcall_participant_map_by_shipcall_id():
+    schemaModel = {"id":152}
+
+    query = SQLQuery.get_shipcall_participant_map_by_shipcall_id()
+    pdata = execute_sql_query_standalone(query=query, param={"id" : schemaModel["id"]}, command_type="query") # existing list of assignments
+
+    assert len(pdata)==4, f"there should be four assigned participants for the shipcall with id {schemaModel.get('id')}"
+    return
+
+def test_sql__get_shipcall__get_spm__optionally_update_shipcall():
+    schemaModel = {'id': 152}
+    query = SQLQuery.get_shipcall_by_id()
+    shipcall = execute_sql_query_standalone(query=query, param={"id" : schemaModel["id"]}, command_type="single", model=model.Shipcall)
+
+    query = SQLQuery.get_shipcall_participant_map_by_shipcall_id()
+    pdata = execute_sql_query_standalone(query=query, param={"id" : shipcall.id}, command_type="query") # existing list of assignments
+
+    assert len(pdata)==4, f"there should be four assigned participants for the shipcall with id {shipcall.id}"
+
+    for participant_assignment in shipcall.participants:
+        found_participant = False
+        for elem in pdata:
+            if elem["participant_id"] == participant_assignment["participant_id"] and elem["type"] == participant_assignment["type"]:
+                found_participant = True
+                break
+        if not found_participant:
+            nquery = SQLQuery.get_shipcall_post_update_shipcall_participant_map()
+            ndata = execute_sql_query_standalone(query=nquery, param={"shipcall_id" : shipcall.id, "participant_id" : participant_assignment["participant_id"], "type" : participant_assignment["type"]}, command_type="execute") # existing list of assignments
+    return
+
+def test_sql__shipcall_post__get_last_insert_id__get_spm__update_participants__verify_changes():
+    """
+    this combinatorial test:
+    1.) creates a novel shipcall
+    2.) obtains the ID of the just-created shipcall
+    3.) reads the participant map for that ID and verifies, that there are no participants listed
+    4.) iteratively updates the participant map of the ID (using proxy data)
+    5.) verifies the update
+    """
+    from BreCal.stubs.shipcall import get_stub_valid_shipcall_shifting, get_stub_valid_ship_loaded_model
+    pooledConnection = local_db.getPoolConnection()
+    commands = pydapper.using(pooledConnection)
+    try:
+
+        # 1.) create shipcall
+        post_data = get_stub_valid_shipcall_shifting()
+        post_data["voyage"] = "pytestRS71" # perform tagging to identify the shipcalls created by pytests (<16 characters, no special characters).
+        schemaModel = get_stub_valid_ship_loaded_model(post_data)
+        query = SQLQuery.get_shipcall_post(schemaModel) # refactored variant of create_sql_query_shipcall_post (more concise)
+        schemas = execute_sql_query_standalone(query=query, param=schemaModel, command_type="execute", pooledConnection=pooledConnection)
+        assert schemas==1, f"unsuccessful query execution. Query: {query}"
+
+        # 2.) obtain the ID of the novel shipcall
+        # within the same pooledConnection, ask for the last inserted id
+        query = SQLQuery.get_shipcall_post_last_insert_id()
+        new_id = commands.execute_scalar(query)
+        assert new_id > 0, f"the new id should be unlike 0.."
+
+        # 3.) read the ShipcallParticipantMap for the novel id
+        query = SQLQuery.get_shipcall_participant_map_by_shipcall_id()
+        pdata = execute_sql_query_standalone(query=query, param={"id" : new_id}, command_type="query") # existing list of assignments
+        assert len(pdata)==0, f"as the POST query does not include participants in this case, the novel id should not have assigned participants."
+
+        ### proxy data ###
+        # loop across passed participant ids, creating entries for those not present in pdata
+        schemaModel = {'id': new_id, "participants":[{'id': 128, 'participant_id': 2, 'type': 4}, {'id': 129, 'participant_id': 3, 'type': 1}, {'id': 130, 'participant_id': 4, 'type': 2}, {'id': 131, 'participant_id': 6, 'type': 8}]}
+
+        # 4.) assign the participants
+        for participant_assignment in schemaModel["participants"]:
+            found_participant = False
+            for elem in pdata:
+                if elem["participant_id"] == participant_assignment["participant_id"] and elem["type"] == participant_assignment["type"]:
+                    found_participant = True
+                    break
+            if not found_participant:
+                nquery = SQLQuery.get_shipcall_post_update_shipcall_participant_map()
+                ndata = execute_sql_query_standalone(query=nquery, param={"shipcall_id" : new_id, "participant_id" : participant_assignment["participant_id"], "type" : participant_assignment["type"]}, command_type="execute") # existing list of assignments
+
+        # 5.) verify the update (5 participants, including the false one)
+        query = SQLQuery.get_shipcall_participant_map_by_shipcall_id()
+        pdata = execute_sql_query_standalone(query=query, param={"id" : new_id}, command_type="query") # existing list of assignments
+        assert len(pdata)==5, f"due to the PUT, there shall now be five participants, as defined in schemaModel."
+
+        # 6.) delete the incorrect participant (last entry in the list in this case)
+        dquery = SQLQuery.get_shipcall_participant_map_delete_by_id()
+        ddata = execute_sql_query_standalone(query=dquery, param={"existing_id" : pdata[-1].get("id")}, command_type="execute")
+
+        # 7.) verify the update (now 4 participants)
+        query = SQLQuery.get_shipcall_participant_map_by_shipcall_id()
+        pdata = execute_sql_query_standalone(query=query, param={"id" : new_id}, command_type="query") # existing list of assignments
+        assert len(pdata)==4, f"due to the PUT, there shall now be five participants, as defined in schemaModel."
+
+    finally:
+        pooledConnection.close()
+    return
+
+def test_sql_query_get_shipcalls_is_identical_to_legacy_query():
+    from BreCal.database.sql_queries import create_sql_query_shipcall_get
+
+    options = {'past_days':7}
+    query_refactored = SQLQuery.get_shipcalls(options)
+    query_legacy = create_sql_query_shipcall_get(options)
+
+    assert query_refactored == query_legacy, f"the refactored code to generate the query must be absolutely identical to the legacy version"
+    return
+
+def test_sql_query_post_ship_is_identical_to_legacy_query():
+    from BreCal.database.sql_queries import SQLQuery, create_sql_query_ship_post, create_sql_query_ship_put
+    from BreCal.stubs.ship import get_stub_valid_ship_loaded_model
+
+    schemaModel = get_stub_valid_ship_loaded_model()
+
+    query_refactored = SQLQuery.get_ship_post(schemaModel)
+    query_legacy = create_sql_query_ship_post(schemaModel)
+
+    assert query_refactored == query_legacy, f"the refactored code to generate the query must be absolutely identical to the legacy version"
+    return
+
+def test_sql_query_put_ship_is_identical_to_legacy_query():
+    from BreCal.database.sql_queries import SQLQuery, create_sql_query_ship_post, create_sql_query_ship_put
+    from BreCal.stubs.ship import get_stub_valid_ship_loaded_model
+
+    schemaModel = get_stub_valid_ship_loaded_model()
+    query_refactored = SQLQuery.get_ship_put(schemaModel)
+    query_legacy = create_sql_query_ship_put(schemaModel)
+
+    assert query_refactored == query_legacy, f"the refactored code to generate the query must be absolutely identical to the legacy version"
+    return
+
+
+
+#schemas = execute_sql_query_standalone(query=SQLQuery.get_berth(), param={})
diff --git a/src/server/tests/schemas/test_model.py b/src/server/tests/schemas/test_model.py
new file mode 100644
index 0000000..8944f45
--- /dev/null
+++ b/src/server/tests/schemas/test_model.py
@@ -0,0 +1,80 @@
+from marshmallow import ValidationError
+import pytest
+from BreCal.schemas.model import ShipcallSchema
+
+
+@pytest.fixture(scope="function") # function: destroy fixture at the end of each test
+def prepare_shipcall_content():
+    import datetime
+    from BreCal.stubs.shipcall import get_shipcall_simple
+    shipcall_stub = get_shipcall_simple()
+    content = shipcall_stub.__dict__
+    content["participants"] = []
+    content = {k:v.isoformat() if isinstance(v, datetime.datetime) else v for k,v in content.items()}
+    return locals()
+
+def test_shipcall_input_validation_draft(prepare_shipcall_content):
+    content = prepare_shipcall_content["content"]
+    content["draft"] = 24.11
+
+    schemaModel = ShipcallSchema()
+    with pytest.raises(ValidationError, match="Must be greater than 0 and less than or equal to 20."):
+        loadedModel = schemaModel.load(data=content, many=False, partial=True)
+    return
+
+def test_shipcall_input_validation_voyage(prepare_shipcall_content):
+    content = prepare_shipcall_content["content"]
+    content["voyage"] = "".join(list(map(str,list(range(0,24))))) # 38 characters
+
+    schemaModel = ShipcallSchema()
+    with pytest.raises(ValidationError, match="Longer than maximum length "):
+        loadedModel = schemaModel.load(data=content, many=False, partial=True)
+    return
+
+
+@pytest.fixture(scope="function") # function: destroy fixture at the end of each test
+def prepare_user_content():
+    import datetime
+    from BreCal.stubs.user import get_user_simple
+    from BreCal.schemas.model import UserSchema
+    schemaModel = UserSchema()
+
+    user_stub = get_user_simple()
+    content = user_stub.__dict__
+    content = {k:v.isoformat() if isinstance(v, datetime.datetime) else v for k,v in content.items()}
+    content = {k:v for k,v in content.items() if k in list(schemaModel.fields.keys())}
+    content["old_password"] = "myfavoritedog123"
+    content["new_password"] = "SecuRepassW0rd!"
+    return locals()
+
+
+def test_input_validation_berth_phone_number_is_valid(prepare_user_content):
+    content, schemaModel = prepare_user_content["content"], prepare_user_content["schemaModel"]
+    content["user_phone"] = "+49123 45678912" # whitespace and + are valid
+
+    loadedModel = schemaModel.load(data=content, many=False, partial=True)
+    return
+
+def test_input_validation_berth_phone_number_is_invalid(prepare_user_content):
+    content, schemaModel = prepare_user_content["content"], prepare_user_content["schemaModel"]
+    content["user_phone"] = "+49123 45678912!" # ! is invalid
+
+    with pytest.raises(ValidationError, match="one of the phone number values is not valid."):
+        loadedModel = schemaModel.load(data=content, many=False, partial=True)
+    return
+
+def test_input_validation_new_password_too_short(prepare_user_content):
+    content, schemaModel = prepare_user_content["content"], prepare_user_content["schemaModel"]
+    content["new_password"] = "1234" # must have between 6 and 128 characters
+
+    with pytest.raises(ValidationError, match="Length must be between 6 and 128."):
+        loadedModel = schemaModel.load(data=content, many=False, partial=True)
+    return
+
+def test_input_validation_user_email_invalid(prepare_user_content):
+    content, schemaModel = prepare_user_content["content"], prepare_user_content["schemaModel"]
+    content["user_email"] = "userbrecal.com" # forgot @ -> invalid
+
+    with pytest.raises(ValidationError, match="invalid email address"):
+        loadedModel = schemaModel.load(data=content, many=False, partial=True)
+    return
diff --git a/src/server/tests/test_create_app.py b/src/server/tests/test_create_app.py
index 652ae3d..706e872 100644
--- a/src/server/tests/test_create_app.py
+++ b/src/server/tests/test_create_app.py
@@ -8,13 +8,14 @@ def test_create_app():
     import sys
     from BreCal import get_project_root
 
-    project_root = get_project_root("brecal")
+    project_root = os.path.join(os.path.expanduser("~"), "brecal")
     lib_location = os.path.join(project_root, "src", "server")
     sys.path.append(lib_location)
 
     from BreCal import create_app
     os.chdir(os.path.join(lib_location,"BreCal")) # set the current directory to ~/brecal/src/server/BreCal, so the config is found
-    application = create_app()
+    instance_path = os.path.join(os.path.expanduser('~'), "brecal", "src", "server", "instance", "instance")
+    application = create_app(test_config=None, instance_path=instance_path)
     return
 
 if __name__=="__main__":
diff --git a/src/server/tests/validators/test_input_validation_ship.py b/src/server/tests/validators/test_input_validation_ship.py
new file mode 100644
index 0000000..b1de16e
--- /dev/null
+++ b/src/server/tests/validators/test_input_validation_ship.py
@@ -0,0 +1,226 @@
+import pytest
+
+import os
+import jwt
+import json
+import requests
+import datetime
+import werkzeug
+import re
+from marshmallow import ValidationError
+
+from BreCal import local_db
+from BreCal.schemas import model
+
+from BreCal.impl.ships import GetShips
+
+from BreCal.schemas.model import Participant_Assignment, EvaluationType, ShipcallType
+from BreCal.stubs.ship import get_stub_valid_ship, get_stub_valid_ship_loaded_model
+from BreCal.validators.input_validation import validation_error_default_asserts
+from BreCal.schemas.model import ParticipantType
+from BreCal.validators.input_validation_ship import InputValidationShip
+
+instance_path = os.path.join(os.path.expanduser('~'), "brecal", "src", "server", "instance", "instance")
+local_db.initPool(os.path.dirname(instance_path), connection_filename="connection_data_local.json")
+
+@pytest.fixture(scope="session")
+def get_stub_token():
+    """
+    performs a login to the user 'maxm' and returns the respective url and the token. The token will be used in
+    further requests in the following format (example of post-request):
+        requests.post(f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data)
+
+    """
+    port = 9013
+    url = f"http://127.0.0.1:{port}"
+
+    # set the JWT key
+    os.environ['SECRET_KEY'] = 'zdiTz8P3jXOc7jztIQAoelK4zztyuCpJ'
+
+    try:
+        response = requests.post(f"{url}/login", json=jwt.decode("eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1c2VybmFtZSI6Im1heG0iLCJwYXNzd29yZCI6IlN0YXJ0MTIzNCJ9.uIrbz3g-IwwTLz6C1zXELRGtAtRJ_myYJ4J4x0ozjAI", key=os.environ.get("SECRET_KEY"), algorithms=["HS256"]))
+    except requests.ConnectionError as err:
+        raise AssertionError(f"could not establish a connection to the default url. Did you start an instance of the local database at port {port}? Looking for a connection to {url}")
+    user = response.json()
+    token = user.get("token")
+    return locals()
+
+def test_input_validation_ship_fails_when_length_is_incorrect():
+    with pytest.raises(ValidationError, match=re.escape("Must be greater than 0 and less than 1000.")):
+        post_data = get_stub_valid_ship()
+        post_data["length"] = 0
+        loadedModel = model.ShipSchema().load(data=post_data, many=False, partial=True)
+        
+    with pytest.raises(ValidationError, match=re.escape("Must be greater than 0 and less than 1000.")):
+        post_data = get_stub_valid_ship()
+        post_data["length"] = 1000
+        loadedModel = model.ShipSchema().load(data=post_data, many=False, partial=True)
+
+    # success
+    post_data = get_stub_valid_ship()
+    post_data["length"] = 123
+    loadedModel = model.ShipSchema().load(data=post_data, many=False, partial=True)
+    return
+
+def test_input_validation_ship_fails_when_width_is_incorrect():
+    with pytest.raises(ValidationError, match=re.escape("Must be greater than 0 and less than 100.")):
+        post_data = get_stub_valid_ship()
+        post_data["width"] = 0
+        loadedModel = model.ShipSchema().load(data=post_data, many=False, partial=True)
+
+    with pytest.raises(ValidationError, match=re.escape("Must be greater than 0 and less than 100.")):
+        post_data = get_stub_valid_ship()
+        post_data["width"] = 100
+        loadedModel = model.ShipSchema().load(data=post_data, many=False, partial=True)
+
+    # success
+    post_data = get_stub_valid_ship()
+    post_data["width"] = 12
+    loadedModel = model.ShipSchema().load(data=post_data, many=False, partial=True)
+    return
+
+def test_input_validation_ship_fails_when_name_is_incorrect():
+    with pytest.raises(ValidationError, match=re.escape("'name' argument should have at max. 63 characters")):
+        post_data = get_stub_valid_ship()
+        post_data["name"] = "0123456789012345678901234567890123456789012345678901234567890123"
+        loadedModel = model.ShipSchema().load(data=post_data, many=False, partial=True)
+
+    with pytest.raises(ValidationError, match=re.escape("'name' argument should not have special characters.")):
+        post_data = get_stub_valid_ship()
+        post_data["name"] = '👽'
+        loadedModel = model.ShipSchema().load(data=post_data, many=False, partial=True)
+
+    post_data = get_stub_valid_ship()
+    post_data["name"] = "012345678901234567890123456789012345678901234567890123456789012"
+    loadedModel = model.ShipSchema().load(data=post_data, many=False, partial=True)
+    return
+
+def test_input_validation_ship_fails_when_callsign_is_incorrect():
+    with pytest.raises(ValidationError, match=re.escape("'callsign' argument should not have more than 8 characters")):
+        post_data = get_stub_valid_ship()
+        post_data["callsign"] = "123456789"
+        loadedModel = model.ShipSchema().load(data=post_data, many=False, partial=True)
+
+    with pytest.raises(ValidationError, match=re.escape("'callsign' argument should not have special characters.")):
+        post_data = get_stub_valid_ship()
+        post_data["callsign"] = '👽'
+        loadedModel = model.ShipSchema().load(data=post_data, many=False, partial=True)
+
+    # success
+    post_data = get_stub_valid_ship()
+    post_data["callsign"] = 'PBIO'
+    loadedModel = model.ShipSchema().load(data=post_data, many=False, partial=True)
+
+    # success
+    post_data = get_stub_valid_ship()
+    post_data["callsign"] = None
+    loadedModel = model.ShipSchema().load(data=post_data, many=False, partial=True)
+
+    return
+
+def test_input_validation_ship_fails_when_imo_is_incorrect():
+    # imo must have exactly 7 digits and can't be None
+    with pytest.raises(ValidationError, match=re.escape("'imo' should be a 7-digit number")):
+        post_data = get_stub_valid_ship()
+        post_data["imo"] = 123456
+        loadedModel = model.ShipSchema().load(data=post_data, many=False, partial=True)
+
+    with pytest.raises(ValidationError, match=re.escape("'imo' should be a 7-digit number")):
+        post_data = get_stub_valid_ship()
+        post_data["imo"] = 12345678
+        loadedModel = model.ShipSchema().load(data=post_data, many=False, partial=True)
+
+    with pytest.raises(ValidationError, match=re.escape("Field may not be null.")):
+        post_data = get_stub_valid_ship()
+        post_data["imo"] = None
+        loadedModel = model.ShipSchema().load(data=post_data, many=False, partial=True)
+
+    # success
+    post_data = get_stub_valid_ship()
+    post_data["imo"] = 1234567
+    loadedModel = model.ShipSchema().load(data=post_data, many=False, partial=True)
+    return
+
+def test_input_validation_ship_fails_when_bollard_pull_and_tug_values_are_set():
+    ivs = InputValidationShip()
+
+    with pytest.raises(ValidationError, match=re.escape("'bollard_pull' is only allowed, when a ship is a tug ('is_tug').")):
+        content = {'is_tug':0, 'bollard_pull':230}
+        ivs.optionally_evaluate_bollard_pull_value(content)
+
+    with pytest.raises(ValidationError, match=re.escape("'bollard_pull' is only allowed, when a ship is a tug ('is_tug').")):
+        content = {'is_tug':None, 'bollard_pull':230}
+        ivs.optionally_evaluate_bollard_pull_value(content)
+
+    content = {'is_tug':0, 'bollard_pull':None}
+    ivs.optionally_evaluate_bollard_pull_value(content)
+
+    content = {'is_tug':1, 'bollard_pull':None}
+    ivs.optionally_evaluate_bollard_pull_value(content)
+
+    content = {'is_tug':1, 'bollard_pull':125}
+    ivs.optionally_evaluate_bollard_pull_value(content)
+
+    with pytest.raises(ValidationError, match=re.escape("when a ship is a tug, the bollard pull must be 0 < value < 500.")):
+        content = {'is_tug':1, 'bollard_pull':-1}
+        ivs.optionally_evaluate_bollard_pull_value(content)
+
+    with pytest.raises(ValidationError, match=re.escape("when a ship is a tug, the bollard pull must be 0 < value < 500.")):
+        content = {'is_tug':1, 'bollard_pull':0}
+        ivs.optionally_evaluate_bollard_pull_value(content)
+
+    with pytest.raises(ValidationError, match=re.escape("when a ship is a tug, the bollard pull must be 0 < value < 500.")):
+        content = {'is_tug':1, 'bollard_pull':500}
+        ivs.optionally_evaluate_bollard_pull_value(content)
+
+    with pytest.raises(ValidationError, match=re.escape("when a ship is a tug, the bollard pull must be 0 < value < 500.")):
+        content = {'is_tug':1, 'bollard_pull':501}
+        ivs.optionally_evaluate_bollard_pull_value(content)
+    return
+
+def test_input_validation_ship_post_request_fails_when_ship_imo_already_exists():
+    # get the ships, convert them to a list of JSON dictionaries
+    response, status_code, header = GetShips(token=None)
+    ships = json.loads(response)
+
+    # extract only the 'imo' values
+    ship_imos = [ship.get("imo") for ship in ships]
+
+    post_data = get_stub_valid_ship()
+    post_data["imo"] = ship_imos[-1] # assign one of the IMOs, which already exist
+    loadedModel = get_stub_valid_ship_loaded_model(post_data)
+    content = post_data
+
+    with pytest.raises(ValidationError, match="the provided ship IMO 9186687 already exists. A ship may only be added, if there is no other ship with the same IMO number."):
+        InputValidationShip.check_ship_imo_already_exists(loadedModel)
+    return
+
+
+
+def test_input_validation_ship_put_request_fails_when_ship_imo_should_be_changed():
+    # get the ships, convert them to a list of JSON dictionaries
+    response, status_code, header = GetShips(token=None)
+    ships = json.loads(response)
+    selected_ship = ships[-1] # select one of the ships; in this case the last one.
+
+    put_data = get_stub_valid_ship()
+    put_data["imo"] = selected_ship.get("imo")+1 # assign one of the IMOs, which already exist
+
+    loadedModel = get_stub_valid_ship_loaded_model(put_data)
+    content = put_data
+
+    with pytest.raises(ValidationError, match=re.escape("The IMO number field may not be changed since it serves the purpose of a primary (matching) key.")):
+        InputValidationShip.put_content_may_not_contain_imo_number(content)
+    return
+
+
+def test_input_validation_ship_put_request_fails_when_ship_id_is_missing():
+    put_data = get_stub_valid_ship()
+    put_data.pop("id",None) # make sure there is no ID within the put data for this test
+
+    loadedModel = get_stub_valid_ship_loaded_model(put_data)
+    content = put_data
+
+    with pytest.raises(ValidationError, match="The id field is required."):
+        InputValidationShip.content_contains_ship_id(content)
+    return
diff --git a/src/server/tests/validators/test_input_validation_shipcall.py b/src/server/tests/validators/test_input_validation_shipcall.py
new file mode 100644
index 0000000..925466c
--- /dev/null
+++ b/src/server/tests/validators/test_input_validation_shipcall.py
@@ -0,0 +1,737 @@
+import pytest
+
+import os
+import jwt
+import json
+import requests
+import datetime
+import werkzeug
+from marshmallow import ValidationError
+
+from BreCal import local_db
+
+from BreCal.schemas.model import Participant_Assignment, EvaluationType, ShipcallType
+from BreCal.stubs.shipcall import create_postman_stub_shipcall, get_stub_valid_shipcall_arrival, get_stub_valid_shipcall_departure, get_stub_valid_shipcall_shifting, get_stub_shipcall_arrival_invalid_missing_eta, get_stub_shipcall_shifting_invalid_missing_eta, get_stub_shipcall_shifting_invalid_missing_etd, get_stub_shipcall_arrival_invalid_missing_type, get_stub_shipcall_departure_invalid_missing_etd
+from BreCal.stubs.participant import get_stub_list_of_valid_participants
+from BreCal.validators.input_validation import validation_error_default_asserts
+from BreCal.schemas.model import ParticipantType
+from BreCal.validators.input_validation_shipcall import InputValidationShipcall
+
+instance_path = os.path.join(os.path.expanduser('~'), "brecal", "src", "server", "instance", "instance")
+local_db.initPool(os.path.dirname(instance_path), connection_filename="connection_data_local.json")
+
+@pytest.fixture(scope="session")
+def get_stub_token():
+    """
+    performs a login to the user 'maxm' and returns the respective url and the token. The token will be used in
+    further requests in the following format (example of post-request):
+        requests.post(f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data)
+
+    """
+    port = 9013
+    url = f"http://127.0.0.1:{port}"
+
+    # set the JWT key
+    os.environ['SECRET_KEY'] = 'zdiTz8P3jXOc7jztIQAoelK4zztyuCpJ'
+
+    try:
+        response = requests.post(f"{url}/login", json=jwt.decode("eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1c2VybmFtZSI6Im1heG0iLCJwYXNzd29yZCI6IlN0YXJ0MTIzNCJ9.uIrbz3g-IwwTLz6C1zXELRGtAtRJ_myYJ4J4x0ozjAI", key=os.environ.get("SECRET_KEY"), algorithms=["HS256"]))
+    except requests.ConnectionError as err:
+        raise AssertionError(f"could not establish a connection to the default url. Did you start an instance of the local database at port {port}? Looking for a connection to {url}")
+    user = response.json()
+    token = user.get("token")
+    return locals()
+
+@pytest.fixture(scope="session")
+def get_shipcall_id_after_stub_post_request(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+
+    post_data = get_stub_valid_shipcall_arrival()
+    response = requests.post(
+        f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+    )
+    assert response.status_code==201
+    shipcall_id = response.json().get("id")
+    assert shipcall_id is not None
+    return locals()
+
+def test_shipcall_post_request_fails_when_ship_id_is_invalid(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+
+    post_data = get_stub_valid_shipcall_arrival() # create_postman_stub_shipcall()
+
+    post_data["ship_id"] = 1234562
+    response = requests.post(
+        f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+    )
+
+    with pytest.raises(ValidationError, match=f"provided an invalid ship id"):
+        assert response.status_code==400
+        raise ValidationError(response.json()) # because the response does not raise a ValidationError, we artifically create it to check the pytest.raises outcome
+    return
+
+def test_shipcall_post_request_fails_when_arrival_berth_id_is_invalid(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+
+    post_data = get_stub_valid_shipcall_arrival() # create_postman_stub_shipcall()
+
+    post_data["arrival_berth_id"] = 1234562
+    response = requests.post(
+        f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+    )
+
+    with pytest.raises(ValidationError, match=f"provided an invalid arrival berth id"):
+        assert response.status_code==400
+        raise ValidationError(response.json()) # because the response does not raise a ValidationError, we artifically create it to check the pytest.raises outcome
+    return
+
+def test_shipcall_post_request_fails_when_departure_berth_id_is_invalid(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+
+    post_data = get_stub_valid_shipcall_arrival() # create_postman_stub_shipcall()
+
+    post_data["departure_berth_id"] = 1234562
+    response = requests.post(
+        f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+    )
+
+    with pytest.raises(ValidationError, match=f"provided an invalid departure berth id"):
+        assert response.status_code==400
+        raise ValidationError(response.json()) # because the response does not raise a ValidationError, we artifically create it to check the pytest.raises outcome
+    return
+
+def test_shipcall_post_request_fails_when_participant_ids_are_invalid(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+
+    post_data = get_stub_valid_shipcall_arrival() # create_postman_stub_shipcall()
+
+    post_data["participants"] = [Participant_Assignment(1234562,4).to_json()] # identical to: [{'participant_id': 1234562, 'type': 4}]
+    response = requests.post(
+        f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+    )
+
+    with pytest.raises(ValidationError, match=f"one of the provided participant ids is invalid"):
+        assert response.status_code==400
+        raise ValidationError(response.json()) # because the response does not raise a ValidationError, we artifically create it to check the pytest.raises outcome
+    return
+
+def test_shipcall_post_request_fails_when_forbidden_keys_are_set(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+
+    original_post_data = get_stub_valid_shipcall_arrival() # create_postman_stub_shipcall()
+
+    for forbidden_key, forbidden_value in zip(["canceled", "evaluation", "evaluation_message"], [1, EvaluationType.red.name, "random error message"]):
+        post_data = original_post_data.copy()
+        post_data[forbidden_key] = forbidden_value
+        response = requests.post(
+            f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+        )
+        assert response.status_code==400
+        with pytest.raises(ValidationError, match=f"may not be set on POST. "):
+            raise ValidationError(response.json()) # because the response does not raise a ValidationError, we artifically create it to check the pytest.raises outcome
+    return
+
+def test_shipcall_post_request_fails_when_draft_is_out_of_range(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+
+    post_data = get_stub_valid_shipcall_arrival() # create_postman_stub_shipcall()
+
+    post_data["draft"] = 0
+
+    response = requests.post(f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data)
+    with pytest.raises(ValidationError, match=f"Must be greater than 0 and less than or equal to "):
+        assert response.status_code==400
+        raise ValidationError(response.json()) # because the response does not raise a ValidationError, we artifically create it to check the pytest.raises outcome
+
+    post_data = get_stub_valid_shipcall_arrival() # create_postman_stub_shipcall()
+
+    post_data["draft"] = 21
+
+    response = requests.post(f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data)
+    with pytest.raises(ValidationError, match=f"Must be greater than 0 and less than or equal to "):
+        assert response.status_code==400
+        raise ValidationError(response.json()) # because the response does not raise a ValidationError, we artifically create it to check the pytest.raises outcome
+
+    post_data = get_stub_valid_shipcall_arrival() # create_postman_stub_shipcall()
+
+    post_data["draft"] = 20
+    response = requests.post(f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data)
+    assert response.status_code==201, f"the request should accept 20.0 as a valid 'draft' value"
+    return
+
+def test_shipcall_post_request_fails_when_recommended_tugs_is_out_of_range(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+
+    original_post_data = get_stub_valid_shipcall_arrival() # create_postman_stub_shipcall()
+
+    post_data = original_post_data.copy()
+    post_data["recommended_tugs"] = 10
+    response = requests.post(f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data)
+    assert response.status_code == 201
+
+    post_data = original_post_data.copy()
+    post_data["recommended_tugs"] = 0
+    response = requests.post(f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data)
+    assert response.status_code == 201
+
+    post_data = original_post_data.copy()
+    post_data["recommended_tugs"] = 11
+    response = requests.post(f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data)
+
+    with pytest.raises(ValidationError, match=f"Must be greater than or equal to 0 and less than or equal to"):
+        assert response.status_code==400
+        raise ValidationError(response.json()) # because the response does not raise a ValidationError, we artifically create it to check the pytest.raises outcome
+
+
+def test_shipcall_post_request_fails_when_voyage_string_is_invalid(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+
+    original_post_data = get_stub_valid_shipcall_arrival() # create_postman_stub_shipcall()
+
+    # Accept
+    post_data = original_post_data.copy()
+    post_data["voyage"] = "abcdefghijklmnop"
+    response = requests.post(f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data)
+    assert response.status_code==201
+
+    # Fail: too long string
+    post_data = original_post_data.copy()
+    post_data["voyage"] = "abcdefghijklmnopq"
+    response = requests.post(f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data)
+
+    with pytest.raises(ValidationError, match="Longer than maximum length 16"):
+        assert response.status_code==400
+        raise ValidationError(response.json())
+    
+    # Fail: special characters
+    post_data = original_post_data.copy()
+    post_data["voyage"] = '👽'
+    response = requests.post(f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data)
+
+    with pytest.raises(ValidationError, match="Please use only digits and ASCII letters."):
+        assert response.status_code==400
+        raise ValidationError(response.json())
+    return
+
+def test_shipcall_post_request_fails_when_type_arrival_and_not_in_future(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+
+    original_post_data = get_stub_valid_shipcall_arrival() # create_postman_stub_shipcall()
+
+    # accept
+    post_data = original_post_data.copy()
+    post_data["type"] = ShipcallType.arrival
+    post_data["eta"] = (datetime.datetime.now() + datetime.timedelta(hours=3)).isoformat()
+    response = requests.post(f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data)
+    assert response.status_code == 201
+
+    # error
+    post_data = original_post_data.copy()
+    post_data["type"] = ShipcallType.arrival
+    post_data["eta"] = (datetime.datetime.now() - datetime.timedelta(hours=3)).isoformat()
+    response = requests.post(f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data)
+
+    with pytest.raises(ValidationError, match="must be in the future. Incorrect datetime provided"):
+        assert response.status_code==400
+        raise ValidationError(response.json())
+    return
+
+def test_shipcall_post_request_fails_when_type_departure_and_not_in_future(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+
+    original_post_data = get_stub_valid_shipcall_departure() # create_postman_stub_shipcall()
+
+    # accept
+    post_data = original_post_data.copy()
+    post_data["type"] = ShipcallType.departure
+    post_data["etd"] = (datetime.datetime.now() + datetime.timedelta(hours=3)).isoformat()
+    response = requests.post(f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data)
+    assert response.status_code == 201
+
+    # error
+    post_data = original_post_data.copy()
+    post_data["type"] = ShipcallType.departure
+    post_data["etd"] = (datetime.datetime.now() - datetime.timedelta(hours=3)).isoformat()
+    response = requests.post(f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data)
+
+    with pytest.raises(ValidationError, match="must be in the future. Incorrect datetime provided"):
+        assert response.status_code==400
+        raise ValidationError(response.json())
+    return
+
+def test_shipcall_post_request_fails_when_type_shifting_and_not_in_future(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+
+    original_post_data = get_stub_valid_shipcall_departure() # create_postman_stub_shipcall()
+
+    # accept
+    post_data = original_post_data.copy()
+    post_data["type"] = ShipcallType.departure
+    post_data["eta"] = (datetime.datetime.now() + datetime.timedelta(hours=3)).isoformat()
+    post_data["etd"] = (datetime.datetime.now() + datetime.timedelta(hours=3)).isoformat()
+    response = requests.post(f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data)
+    assert response.status_code == 201
+
+    # error
+    post_data = original_post_data.copy()
+    post_data["type"] = ShipcallType.departure
+    post_data["eta"] = (datetime.datetime.now() + datetime.timedelta(hours=3)).isoformat()
+    post_data["etd"] = (datetime.datetime.now() - datetime.timedelta(hours=3)).isoformat()
+    response = requests.post(f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data)
+
+    with pytest.raises(ValidationError, match="must be in the future. Incorrect datetime provided"):
+        assert response.status_code==400
+        raise ValidationError(response.json())
+    return
+
+def test_shipcall_post_request_fails_when_type_arrival_and_missing_eta(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+
+    original_post_data = get_stub_valid_shipcall_arrival() # create_postman_stub_shipcall()
+
+    post_data = original_post_data.copy()
+    post_data.pop("eta", None)
+    post_data["type"] = ShipcallType.arrival
+    response = requests.post(f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data)
+
+    with pytest.raises(ValidationError, match="Missing key!"):
+        assert response.status_code==400
+        raise ValidationError(response.json())
+    return
+
+def test_shipcall_post_request_fails_when_type_departure_and_missing_etd(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+
+    original_post_data = get_stub_valid_shipcall_arrival() # create_postman_stub_shipcall()
+
+    post_data = original_post_data.copy()
+    post_data.pop("etd", None)
+    post_data["type"] = ShipcallType.departure
+    response = requests.post(f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data)
+
+    with pytest.raises(ValidationError, match="Missing key!"):
+        assert response.status_code==400
+        raise ValidationError(response.json())
+    return
+
+def test_shipcall_post_request_fails_when_type_shifting_and_missing_eta(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+
+    original_post_data = get_stub_valid_shipcall_arrival() # create_postman_stub_shipcall()
+
+    post_data = original_post_data.copy()
+    post_data["type"] = ShipcallType.departure
+    post_data.pop("eta", None)
+    post_data["etd"] = (datetime.datetime.now() + datetime.timedelta(hours=3)).isoformat()
+    response = requests.post(f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data)
+
+    with pytest.raises(ValidationError, match="Missing key!"):
+        assert response.status_code==400
+        raise ValidationError(response.json())
+    return
+
+def test_shipcall_post_request_fails_when_type_shifting_and_missing_etd(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+
+    original_post_data = get_stub_valid_shipcall_arrival() # create_postman_stub_shipcall()
+
+    post_data = original_post_data.copy()
+    post_data["type"] = ShipcallType.departure
+    post_data["eta"] = (datetime.datetime.now() + datetime.timedelta(hours=3)).isoformat()
+    post_data.pop("etd", None)
+    response = requests.post(f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data)
+
+    with pytest.raises(ValidationError, match="Missing key!"):
+        assert response.status_code==400
+        raise ValidationError(response.json())
+    return
+
+
+
+def test_shipcall_post_invalid_tidal_window_to_smaller_than_tidal_window_from(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+
+    post_data = get_stub_valid_shipcall_shifting()
+    post_data["tidal_window_to"] = (datetime.datetime.fromisoformat(post_data["tidal_window_from"])-datetime.timedelta(minutes=1)).isoformat()
+
+    response = requests.post(
+        f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+    )
+    validation_error_default_asserts(response)
+    assert "\'tidal_window_to\' must take place after \'tidal_window_from\'" in response.json().get("message","")
+    return
+
+def test_shipcall_post_invalid_tidal_windows_must_be_in_future(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+
+    post_data = get_stub_valid_shipcall_shifting()
+    post_data["tidal_window_from"] = (datetime.datetime.now()-datetime.timedelta(minutes=1)).isoformat()
+
+    response = requests.post(
+        f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+    )
+    validation_error_default_asserts(response)
+    assert "\'tidal_window_from\' must be in the future. " in response.json().get("message","")
+
+    post_data = get_stub_valid_shipcall_shifting()
+    post_data["tidal_window_to"] = (datetime.datetime.now()-datetime.timedelta(minutes=1)).isoformat()
+
+    response = requests.post(
+        f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+    )
+    validation_error_default_asserts(response)
+    assert "\'tidal_window_to\' must be in the future. " in response.json().get("message","")
+    return
+
+def test_shipcall_post_invalid_canceled_must_not_be_set(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+    stubs = [("canceled", 1), ("evaluation", "green"), ("evaluation_message", "this is an error message")]
+
+    for key, value in stubs:
+        post_data = get_stub_valid_shipcall_shifting()
+        post_data[key] = value
+
+        response = requests.post(
+            f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+        )
+        validation_error_default_asserts(response)
+        assert f"\'{key}\' may not be set on POST. Found:" in response.json().get("message","")
+    return
+
+def test_shipcall_post_invalid_participant_type_listed_multiple_times(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+    participants = get_stub_list_of_valid_participants()
+
+    # create double entry for 'id' and 'type'. Either of the two should raise an exception.
+    participants.append(participants[0])
+
+    post_data = get_stub_valid_shipcall_shifting()
+    post_data["participants"] = participants
+
+    response = requests.post(
+        f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+    )
+    validation_error_default_asserts(response)
+    assert f"every participant id and type should be listed only once. Found multiple entries for one of the participants." in response.json().get("message","")
+    return
+
+def test_shipcall_post_invalid_participants_missing_agency(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+
+    post_data = {}
+    response = requests.get(
+        f"{url}/participants", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+    )
+    participants = response.json()
+    participant_id_dict = {item.get("id"):{"participant_id":item.get("id"), "type":item.get("type")} for item in response.json()}
+
+    # e.g., [{'participant_id': 2, 'type': 4}, {'participant_id': 3, 'type': 1}, {'participant_id': 4, 'type': 2}]
+    participants = [participant_id_dict[2], participant_id_dict[3], participant_id_dict[4]]
+
+    post_data = get_stub_valid_shipcall_shifting()
+    post_data["participants"] = participants
+
+    response = requests.post(
+        f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+    )
+    validation_error_default_asserts(response)
+    assert "One of the assigned participants *must* be of type \'ParticipantType.AGENCY\'" in response.json().get("message","")
+    return
+
+def test_shipcall_post_invalid_etd_smaller_than_eta(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+
+    post_data = get_stub_valid_shipcall_shifting()
+    post_data["etd"] = (datetime.datetime.fromisoformat(post_data["eta"])-datetime.timedelta(minutes=1)).isoformat()
+
+    response = requests.post(
+        f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+    )
+    validation_error_default_asserts(response)
+    assert "\'etd\' must be larger than \'eta\'. " in response.json().get("message","")
+    return
+
+def test_shipcall_post_invalid_eta_and_etd_must_be_in_future(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+
+    post_data = get_stub_valid_shipcall_shifting()
+    post_data["etd"] = (datetime.datetime.now()-datetime.timedelta(minutes=1)).isoformat()
+
+    response = requests.post(
+        f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+    )
+    validation_error_default_asserts(response)
+    assert "\'eta\' and \'etd\' must be in the future. " in response.json().get("message","")
+
+    post_data = get_stub_valid_shipcall_shifting()
+    post_data["eta"] = (datetime.datetime.now()-datetime.timedelta(minutes=1)).isoformat()
+
+    response = requests.post(
+        f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+    )
+    validation_error_default_asserts(response)
+    assert "\'eta\' and \'etd\' must be in the future. " in response.json().get("message","")
+    return
+
+def test_shipcall_post_request_missing_mandatory_keys(get_stub_token): # fixture: some sort of local API start in the background
+    """
+    creates a valid shipcall entry and modifies it, by dropping one of the mandatory keys. This test ensures,
+    that each mandatory key raises a ValidationError, when the key is missing.
+    """
+    url = get_stub_token.get("url")
+    token = get_stub_token.get("token")
+
+    post_data = get_stub_shipcall_arrival_invalid_missing_eta()
+    response = requests.post(
+        f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+    )
+    validation_error_default_asserts(response)
+    assert "providing \'eta\' is mandatory." in response.json().get("message","")
+
+    post_data = get_stub_shipcall_departure_invalid_missing_etd()
+    response = requests.post(
+        f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+    )
+    validation_error_default_asserts(response)
+    assert "providing \'etd\' is mandatory." in response.json().get("message","")
+
+    post_data = get_stub_shipcall_shifting_invalid_missing_eta()
+    response = requests.post(
+        f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+    )
+    validation_error_default_asserts(response)
+    assert "providing \'eta\' and \'etd\' is mandatory." in response.json().get("message","")
+
+    post_data = get_stub_shipcall_shifting_invalid_missing_etd()
+    response = requests.post(
+        f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+    )
+    validation_error_default_asserts(response)
+    assert "providing \'eta\' and \'etd\' is mandatory." in response.json().get("message","")
+
+    # the following keys all share the same logic and will be tested in sequence
+    for KEY in ["eta", "arrival_berth_id", "type", "ship_id"]:
+
+        # artificially remove the KEY from a valid shipcall entry
+        post_data = get_stub_valid_shipcall_arrival()
+        post_data.pop(KEY,None)
+
+        response = requests.post(
+            f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+        )
+        validation_error_default_asserts(response)
+        assert f"providing \'{KEY}\' is mandatory." in response.json().get("message","")
+
+    # BERTH ID (arrival or departure, based on type)
+    post_data = get_stub_valid_shipcall_arrival()
+    post_data.pop("arrival_berth_id",None)
+
+    response = requests.post(
+        f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+    )
+    validation_error_default_asserts(response)
+    assert "providing \'arrival_berth_id\' is mandatory." in response.json().get("message","")
+
+
+    post_data = get_stub_valid_shipcall_departure()
+    post_data.pop("departure_berth_id",None)
+
+    response = requests.post(
+        f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+    )
+    validation_error_default_asserts(response)
+    assert "providing \'departure_berth_id\' is mandatory." in response.json().get("message","")
+
+
+    post_data = get_stub_valid_shipcall_shifting()
+    post_data.pop("arrival_berth_id",None)
+
+    response = requests.post(
+        f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+    )
+    validation_error_default_asserts(response)
+    assert "providing \'arrival_berth_id\' & \'departure_berth_id\' is mandatory." in response.json().get("message","")
+
+
+    post_data = get_stub_valid_shipcall_shifting()
+    post_data.pop("departure_berth_id",None)
+
+    response = requests.post(
+        f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+    )
+    validation_error_default_asserts(response)
+    assert "providing \'arrival_berth_id\' & \'departure_berth_id\' is mandatory." in response.json().get("message","")
+
+    return
+
+
+def test_shipcall_post_invalid_agency_missing_participant_list(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+
+    post_data = get_stub_valid_shipcall_shifting()
+
+    # keep all participants, but drop the agency
+    post_data["participants"] = [
+        participant for participant in post_data.get("participants")
+        if not int(participant.get("type")) == int(ParticipantType.AGENCY)
+    ]
+
+    response = requests.post(
+        f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+    )
+    validation_error_default_asserts(response)
+    assert "One of the assigned participants *must* be of type \'ParticipantType.AGENCY\'" in response.json().get("message","")
+    return
+
+def test_shipcall_post_type_is_wrong(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+
+    post_data = get_stub_valid_shipcall_arrival()
+
+    # type 1 should be successful (201)
+    post_data["type"] = 1
+
+    response = requests.post(
+        f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+    )
+    assert response.status_code == 201
+
+    # type 51 should not be successful (400 BAD REQUEST)
+    post_data["type"] = 51
+
+    response = requests.post(
+        f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, json=post_data
+    )
+    validation_error_default_asserts(response)
+    return
+
+def test_shipcall_put_request_fails_when_different_participant_id_is_assigned(get_shipcall_id_after_stub_post_request):
+    url, token, shipcall_id = get_shipcall_id_after_stub_post_request["token"], get_shipcall_id_after_stub_post_request["url"], get_shipcall_id_after_stub_post_request["shipcall_id"]
+
+    post_data = get_stub_valid_shipcall_arrival()
+    post_data["id"] = shipcall_id
+
+    user_data = {'id':6, 'participant_id':1}
+    loadedModel = post_data
+    content = post_data
+    spm_shipcall_data = [{'participant_id': 6, 'type': 4},
+    {'participant_id': 3, 'type': 1},
+    {'participant_id': 4, 'type': 2},
+    {'participant_id': 5, 'type': 8}]
+
+
+    # agency with different participant id is assigned
+    ivs = InputValidationShipcall()
+    with pytest.raises(werkzeug.exceptions.Forbidden, match=f"A different participant_id is assigned as the AGENCY of this shipcall. "):
+        ivs.check_agency_in_shipcall_participant_map(user_data, loadedModel, content, spm_shipcall_data)
+    return
+
+
+def test_shipcall_put_request_success(get_shipcall_id_after_stub_post_request):
+    url, token, shipcall_id = get_shipcall_id_after_stub_post_request["token"], get_shipcall_id_after_stub_post_request["url"], get_shipcall_id_after_stub_post_request["shipcall_id"]
+
+    post_data = get_stub_valid_shipcall_arrival()
+    post_data["id"] = shipcall_id
+
+    # success happens, when shipcall data is valid, the user is authorized and the assigned spm shipcall data is suitable
+    user_data = {'id':6, 'participant_id':1}
+    loadedModel = post_data
+    content = post_data
+    spm_shipcall_data = [{'participant_id': 6, 'type': 8},
+        {'participant_id': 3, 'type': 1},
+        {'participant_id': 4, 'type': 2},
+        {'participant_id': 5, 'type': 4}]
+
+
+    # success
+    ivs = InputValidationShipcall()
+    ivs.check_agency_in_shipcall_participant_map(user_data, loadedModel, content, spm_shipcall_data)
+    return
+
+def test_shipcall_put_request_fails_when_no_agency_is_assigned(get_shipcall_id_after_stub_post_request):
+    url, token, shipcall_id = get_shipcall_id_after_stub_post_request["token"], get_shipcall_id_after_stub_post_request["url"], get_shipcall_id_after_stub_post_request["shipcall_id"]
+
+    post_data = get_stub_valid_shipcall_arrival()
+    post_data["id"] = shipcall_id
+
+    user_data = {'id':6, 'participant_id':1}
+    loadedModel = post_data
+    content = post_data
+    spm_shipcall_data = [
+    {'participant_id': 3, 'type': 1},
+    {'participant_id': 4, 'type': 2},
+    {'participant_id': 5, 'type': 4}]
+
+
+    # no agency assigned
+    ivs = InputValidationShipcall()
+    with pytest.raises(werkzeug.exceptions.Forbidden, match=f"There is no assigned agency for this shipcall."):
+     ivs.check_agency_in_shipcall_participant_map(user_data, loadedModel, content, spm_shipcall_data)
+    return
+
+def test_shipcall_put_request_fails_when_user_is_not_authorized(get_shipcall_id_after_stub_post_request):
+    url, token, shipcall_id = get_shipcall_id_after_stub_post_request["token"], get_shipcall_id_after_stub_post_request["url"], get_shipcall_id_after_stub_post_request["shipcall_id"]
+
+    post_data = get_stub_valid_shipcall_arrival()
+    post_data["id"] = shipcall_id
+
+    # user '1' is artificially set as participant 2, which has ParticipantType 4 (pilot), and is not authorized as an agency
+    user_data = {'id':1, 'participant_id':2}
+    loadedModel = post_data
+    content = post_data
+    spm_shipcall_data = [
+    {'participant_id': 2, 'type': 8},
+    {'participant_id': 3, 'type': 1},
+    {'participant_id': 4, 'type': 2},
+    {'participant_id': 5, 'type': 4}]
+
+
+    # current user is not authorized
+    ivs = InputValidationShipcall()
+    with pytest.raises(werkzeug.exceptions.Forbidden, match=f"PUT Requests for shipcalls can only be issued by AGENCY or BSMD users."):
+        ivs.check_agency_in_shipcall_participant_map(user_data, loadedModel, content, spm_shipcall_data)
+    return
+
+def test_shipcall_put_request_fails_when_user_tries_self_assignment(get_shipcall_id_after_stub_post_request):
+    url, token, shipcall_id = get_shipcall_id_after_stub_post_request["token"], get_shipcall_id_after_stub_post_request["url"], get_shipcall_id_after_stub_post_request["shipcall_id"]
+
+    post_data = get_stub_valid_shipcall_arrival()
+    post_data["id"] = shipcall_id
+
+    user_data = {'id':1, 'participant_id':6}
+    loadedModel = post_data
+    content = post_data
+    spm_shipcall_data = [{'participant_id': 6, 'type': 8},
+    {'participant_id': 3, 'type': 1},
+    {'participant_id': 4, 'type': 2},
+    {'participant_id': 5, 'type': 4}]
+
+
+    # self-assignment. User is participant 6, and wants to assign participant 6. 
+    ivs = InputValidationShipcall()
+    with pytest.raises(werkzeug.exceptions.Forbidden, match=f"An agency cannot self-register for a shipcall. The request is issued by an agency-user and tries to assign an AGENCY as the participant of the shipcall."):
+        ivs.check_agency_in_shipcall_participant_map(user_data, loadedModel, content, spm_shipcall_data)
+    return
+
+def test_shipcall_put_request_fails_input_validation_shipcall_when_shipcall_is_canceled(get_stub_token):
+    url, token = get_stub_token["url"], get_stub_token["token"]
+
+    # get all shipcalls and grab shipcall with ID 4
+    # #TODO: there must be a better way to accomplish this easily...
+    response = requests.get(f"{url}/shipcalls", headers={"Content-Type":"text", "Authorization":f"Bearer {token}"}, params={"past_days":30000})
+    assert response.status_code==200
+    assert isinstance(response.json(), list)
+    shipcalls = response.json()
+
+    shipcall_id = 4
+    sh4 = [sh for sh in shipcalls if sh.get("id")==shipcall_id][0]
+    put_data = {k:v for k,v in sh4.items() if k in ["eta", "type", "ship_id", "arrival_berth_id", "participants"]}
+    put_data["id"] = shipcall_id
+
+    loadedModel = put_data
+    content = put_data
+
+    # a canceled shipcall cannot be selected
+    with pytest.raises(ValidationError, match="The shipcall with id 'shipcall_id' is canceled. A canceled shipcall may not be changed."):
+        InputValidationShipcall.check_shipcall_is_canceled(loadedModel, content)
+    return
diff --git a/src/server/tests/validators/test_input_validation_times.py b/src/server/tests/validators/test_input_validation_times.py
new file mode 100644
index 0000000..98a2689
--- /dev/null
+++ b/src/server/tests/validators/test_input_validation_times.py
@@ -0,0 +1,398 @@
+import pytest
+
+import os
+import random
+import datetime
+from marshmallow import ValidationError
+
+from BreCal import local_db
+from BreCal.schemas import model
+
+from BreCal.schemas.model import ParticipantType
+from BreCal.validators.input_validation_times import InputValidationTimes
+
+from BreCal.stubs.times_full import get_valid_stub_times, get_valid_stub_for_pytests
+
+instance_path = os.path.join(os.path.expanduser('~'), "brecal", "src", "server", "instance", "instance")
+local_db.initPool(os.path.dirname(instance_path), connection_filename="connection_data_local.json")
+
+
+def test_input_validation_times_fails_when_berth_info_exceeds_length_limit():
+    # success
+    post_data = get_valid_stub_times()
+    post_data["berth_info"] = "a"*512 # 512 characters
+    model.TimesSchema().load(data=post_data, many=False, partial=True)
+
+    post_data["berth_info"] = "" # 0 characters
+    model.TimesSchema().load(data=post_data, many=False, partial=True)
+
+    # failure
+    with pytest.raises(ValidationError, match="Longer than maximum length 512."):
+        post_data["berth_info"] = "a"*513 # 513 characters
+        model.TimesSchema().load(data=post_data, many=False, partial=True)
+    return
+
+def test_input_validation_times_fails_when_remarks_exceeds_length_limit():
+    # success
+    post_data = get_valid_stub_times()
+    post_data["remarks"] = "a"*512 # 512 characters
+    model.TimesSchema().load(data=post_data, many=False, partial=True)
+
+    post_data["remarks"] = "" # 0 characters
+    model.TimesSchema().load(data=post_data, many=False, partial=True)
+
+    # failure
+    with pytest.raises(ValidationError, match="Longer than maximum length 512."):
+        post_data["remarks"] = "a"*513 # 513 characters
+        model.TimesSchema().load(data=post_data, many=False, partial=True)
+    return
+
+def test_input_validation_times_fails_when_participant_type_is_bsmd():
+    # BSMD -> Failure
+    post_data = get_valid_stub_times()
+    post_data["participant_type"] = int(ParticipantType.BSMD)
+    with pytest.raises(ValidationError, match="the participant_type must not be .BSMD"):
+        model.TimesSchema().load(data=post_data, many=False, partial=True)
+
+    # IntFlag property: BSMD & AGENCY -> Failure
+    post_data = get_valid_stub_times()
+    post_data["participant_type"] = int(ParticipantType(ParticipantType.BSMD+ParticipantType.AGENCY))
+    with pytest.raises(ValidationError, match="the participant_type must not be .BSMD"):
+        model.TimesSchema().load(data=post_data, many=False, partial=True)
+    return
+
+def test_input_validation_times_fails_when_time_key_is_not_reasonable():
+    """
+    every time key (e.g., 'eta_berth' or 'zone_entry') must be reasonable. The validation expects
+    these values to be 'in the future' (larger than datetime.datetime.now()) and not 'in the too distant future'
+    (e.g., more than one year from now.)
+    """
+    for time_key in ["eta_berth", "etd_berth", "lock_time", "zone_entry", "operations_start", "operations_end"]:
+        post_data = get_valid_stub_times()
+
+        # success
+        post_data[time_key] = (datetime.datetime.now() + datetime.timedelta(minutes=11)).isoformat()
+        model.TimesSchema().load(data=post_data, many=False, partial=True)
+
+        # fails
+        with pytest.raises(ValidationError, match="The provided value must be in the future."):
+            post_data[time_key] = (datetime.datetime.now() - datetime.timedelta(minutes=11)).isoformat()
+            model.TimesSchema().load(data=post_data, many=False, partial=True)
+
+        # fails
+        with pytest.raises(ValidationError, match="The provided value is in the too distant future and exceeds a threshold for 'reasonable' entries."):
+            post_data[time_key] = (datetime.datetime.now() + datetime.timedelta(days=367)).isoformat()
+            model.TimesSchema().load(data=post_data, many=False, partial=True)
+    return
+
+def test_input_validation_times_fails_when_user_is_bsmd_user():
+    # create stub-data for a POST request
+    from BreCal.services.jwt_handler import decode_jwt
+    from BreCal.database.sql_utils import get_user_data_for_id
+    import re
+
+    # user 4 is a BSMD user -> fails
+    user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=4)
+
+    with pytest.raises(ValidationError, match=re.escape("current user belongs to BSMD. Cannot post 'times' datasets.")):
+        InputValidationTimes.check_user_is_not_bsmd_type(user_data)
+
+    # user 13 is not a BSMD user -> passes
+    user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=13)
+
+    # success
+    InputValidationTimes.check_user_is_not_bsmd_type(user_data)
+    return
+
+def test_input_validation_times_fails_when_participant_type_entry_already_exists():
+    # the participant type already has an entry -> fails
+    with pytest.raises(ValidationError, match="A dataset for the participant type is already present. Participant Type:"):
+        user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=3)
+        loadedModel["participant_type"] = int(ParticipantType.AGENCY)
+
+        # 2.) datasets may only be created, if the respective participant type did not already create one.
+        InputValidationTimes.check_if_entry_already_exists_for_participant_type(user_data, loadedModel, content)
+    return
+
+def test_input_validation_times_fails_when_participant_type_deviates_from_shipcall_participant_map():
+    # success
+    # user id 3 is assigned as participant_type=4, but the stub assigns participant_type=4
+    user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=3)
+    InputValidationTimes.check_if_user_fits_shipcall_participant_map(user_data, loadedModel, content)
+
+    # fails
+    # user id 4 is assigned as participant_type=1, but the stub assigns participant_type=4
+    with pytest.raises(ValidationError, match="is assigned to the shipcall in a different role."):
+        user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=4)
+        InputValidationTimes.check_if_user_fits_shipcall_participant_map(user_data, loadedModel, content)
+    return
+
+def test_input_validation_times_fails_when_id_references_do_not_exist():
+    # success: all IDs exist
+    user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=3)
+    InputValidationTimes.check_dataset_references(content)
+
+    # fails: IDs do not exist
+    # iterates once for each, berth_id, shipcall_id, participant_id and generates an artificial, non-existing ID
+    for key in ["berth_id", "shipcall_id", "participant_id"]:
+        user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=3)
+        content[key] = loadedModel[key] = 9912737
+
+        with pytest.raises(ValidationError, match=f"The referenced {key} '{content[key]}' does not exist in the database."):
+            InputValidationTimes.check_dataset_references(content)
+    return
+
+from BreCal.schemas.model import ParticipantType
+
+
+def test_input_validation_times_fails_when_missing_required_fields_arrival():
+    """
+    evaluates every individual combination of arriving shipcalls, where one of the required values is arbitrarily missing
+    randomly selects one of the non-terminal ParticipantTypes, which are reasonable (not .BSMD), and validates. This makes sure,
+    that over time, every possible combination has been tested.
+    """
+    # arrival + not-terminal
+    non_terminal_list = [ParticipantType.AGENCY, ParticipantType.MOORING, ParticipantType.PILOT, ParticipantType.PORT_ADMINISTRATION, ParticipantType.TUG]
+    for key in ["eta_berth"]+InputValidationTimes.get_post_data_type_independent_fields():
+        random_participant_type_for_unit_test = random.sample(non_terminal_list,k=1)[0]
+
+        # pass: all required fields exist for the current shipcall type (arrival/incoming)
+        user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=3)
+        loadedModel["shipcall_id"] = content["shipcall_id"] = 222
+        loadedModel["participant_type"] = random_participant_type_for_unit_test
+        content["participant_type"] = int(random_participant_type_for_unit_test)
+        InputValidationTimes.check_times_required_fields_post_data(loadedModel, content)
+
+        # fails: iteratively creates stubs, where one of the required keys is missing
+        user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=3)
+        loadedModel["shipcall_id"] = content["shipcall_id"] = 222
+        loadedModel["participant_type"] = random_participant_type_for_unit_test
+        content["participant_type"] = int(random_participant_type_for_unit_test)
+        with pytest.raises(ValidationError, match="At least one of the required fields is missing. Missing:"):
+            loadedModel[key] = content[key] = None
+            InputValidationTimes.check_times_required_fields_post_data(loadedModel, content)
+
+    # arrival + terminal
+    for key in ["operations_start"]+InputValidationTimes.get_post_data_type_independent_fields():
+        # pass: all required fields exist for the current shipcall type (arrival/incoming)
+        user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=3)
+        loadedModel["shipcall_id"] = content["shipcall_id"] = 222
+        loadedModel["participant_type"] = ParticipantType.TERMINAL
+        content["participant_type"] = int(ParticipantType.TERMINAL)
+        InputValidationTimes.check_times_required_fields_post_data(loadedModel, content)
+
+        # fails: iteratively creates stubs, where one of the required keys is missing
+        user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=3)
+        loadedModel["shipcall_id"] = content["shipcall_id"] = 222
+        loadedModel["participant_type"] = ParticipantType.TERMINAL
+        content["participant_type"] = int(ParticipantType.TERMINAL)
+
+        with pytest.raises(ValidationError, match="At least one of the required fields is missing. Missing:"):
+            loadedModel[key] = content[key] = None
+            InputValidationTimes.check_times_required_fields_post_data(loadedModel, content)
+    return
+
+def test_input_validation_times_fails_when_missing_required_fields_departure():
+    """
+    evaluates every individual combination of departing shipcalls, where one of the required values is arbitrarily missing
+    randomly selects one of the non-terminal ParticipantTypes, which are reasonable (not .BSMD), and validates. This makes sure,
+    that over time, every possible combination has been tested.
+    """
+    # departure + not-terminal
+    non_terminal_list = [ParticipantType.AGENCY, ParticipantType.MOORING, ParticipantType.PILOT, ParticipantType.PORT_ADMINISTRATION, ParticipantType.TUG]
+
+    for key in ["etd_berth"]+InputValidationTimes.get_post_data_type_independent_fields():
+        # select a *random* particiipant type, which is reasonable and *not* TERMINAL, and validate the function.
+        random_participant_type_for_unit_test = random.sample(non_terminal_list,k=1)[0]
+
+        # pass
+        user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=3)
+        loadedModel["shipcall_id"] = content["shipcall_id"] = 241
+        loadedModel["participant_type"] = random_participant_type_for_unit_test
+        content["participant_type"] = int(random_participant_type_for_unit_test)
+        InputValidationTimes.check_times_required_fields_post_data(loadedModel, content)
+
+        # fails: iteratively creates stubs, where one of the required keys is missing
+        user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=3)
+        loadedModel["shipcall_id"] = content["shipcall_id"] = 241
+        loadedModel["participant_type"] = random_participant_type_for_unit_test
+        content["participant_type"] = int(random_participant_type_for_unit_test)
+        with pytest.raises(ValidationError, match="At least one of the required fields is missing. Missing:"):
+            loadedModel[key] = content[key] = None
+            InputValidationTimes.check_times_required_fields_post_data(loadedModel, content)
+
+    # departure + terminal
+    for key in ["operations_end"]+InputValidationTimes.get_post_data_type_independent_fields():
+        # pass
+        user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=3)
+        loadedModel["shipcall_id"] = content["shipcall_id"] = 241
+        loadedModel["participant_type"] = ParticipantType.TERMINAL
+        content["participant_type"] = int(ParticipantType.TERMINAL)
+        InputValidationTimes.check_times_required_fields_post_data(loadedModel, content)
+
+        # fails: iteratively creates stubs, where one of the required keys is missing
+        user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=3)
+        loadedModel["shipcall_id"] = content["shipcall_id"] = 241
+        loadedModel["participant_type"] = ParticipantType.TERMINAL
+        content["participant_type"] = int(ParticipantType.TERMINAL)
+        with pytest.raises(ValidationError, match="At least one of the required fields is missing. Missing:"):
+            loadedModel[key] = content[key] = None
+            InputValidationTimes.check_times_required_fields_post_data(loadedModel, content)
+    return
+
+def test_input_validation_times_fails_when_missing_required_fields_shifting():
+    """
+    evaluates every individual combination of shifting shipcalls, where one of the required values is arbitrarily missing
+    randomly selects one of the non-terminal ParticipantTypes, which are reasonable (not .BSMD), and validates. This makes sure,
+    that over time, every possible combination has been tested.
+    """
+    # shifting + not-terminal
+    non_terminal_list = [ParticipantType.AGENCY, ParticipantType.MOORING, ParticipantType.PILOT, ParticipantType.PORT_ADMINISTRATION, ParticipantType.TUG]
+    for key in ["eta_berth", "etd_berth"]+InputValidationTimes.get_post_data_type_independent_fields():
+        # select a *random* particiipant type, which is reasonable and *not* TERMINAL, and validate the function.
+        random_participant_type_for_unit_test = random.sample(non_terminal_list,k=1)[0]
+        # pass: all required fields exist for the current shipcall type (arrival/incoming)
+        user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=3)
+        loadedModel["shipcall_id"] = content["shipcall_id"] = 189
+        loadedModel["participant_type"] =random_participant_type_for_unit_test
+        content["participant_type"] = int(random_participant_type_for_unit_test)
+        InputValidationTimes.check_times_required_fields_post_data(loadedModel, content)
+
+        # fails: iteratively creates stubs, where one of the required keys is missing
+        user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=3)
+        loadedModel["shipcall_id"] = content["shipcall_id"] = 189
+        loadedModel["participant_type"] = random_participant_type_for_unit_test
+        content["participant_type"] = int(random_participant_type_for_unit_test)
+        with pytest.raises(ValidationError, match="At least one of the required fields is missing. Missing:"):
+            loadedModel[key] = content[key] = None
+            InputValidationTimes.check_times_required_fields_post_data(loadedModel, content)
+
+    # shifting + terminal
+    for key in ["operations_start", "operations_end"]+InputValidationTimes.get_post_data_type_independent_fields():
+        # pass: all required fields exist for the current shipcall type (arrival/incoming)
+        user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=3)
+        loadedModel["shipcall_id"] = content["shipcall_id"] = 189
+        loadedModel["participant_type"] = ParticipantType.TERMINAL
+        content["participant_type"] = int(ParticipantType.TERMINAL)
+        InputValidationTimes.check_times_required_fields_post_data(loadedModel, content)
+
+        # fails: iteratively creates stubs, where one of the required keys is missing
+        user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=3)
+        loadedModel["shipcall_id"] = content["shipcall_id"] = 189
+        loadedModel["participant_type"] = ParticipantType.TERMINAL
+        content["participant_type"] = int(ParticipantType.TERMINAL)
+        with pytest.raises(ValidationError, match="At least one of the required fields is missing. Missing:"):
+            loadedModel[key] = content[key] = None
+            InputValidationTimes.check_times_required_fields_post_data(loadedModel, content)
+    return
+
+
+
+def test_input_validation_times_fails_when_participant_type_is_not_assigned__or__user_does_not_belong_to_the_same_participant_id():
+    """
+    There are two failure cases in InputValidationTimes.check_user_belongs_to_same_group_as_dataset_determines
+        1.) when the participant type is simply not assigned
+        2.) when the participant type matches to the user, but the participant_id is not assigned
+
+    Test case: 
+        shipcall_id 222 is assigned to the participants {"participant_id": 136, "type":2} and {"participant_id": 136, "type":8}
+
+    Case 1:
+        When user_id 3 should be set as participant_type 4, the call fails, because type 4 is not assigned
+
+    Case 2:
+        When user_id 2 (participant_id 2) should be set as participant_type 2, the call fails even though type 2 exists, 
+        because participant_id 136 is assigned
+
+    Case 3:
+        When user_id 28 (participant_id 136) is set as participant_type 2, the call passes.
+    """
+    # fails: participant type 4 does not exist
+    user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=3)
+    participant_type = 4
+    loadedModel["shipcall_id"] = content["shipcall_id"] = 222
+    loadedModel["participant_id"] = content["participant_id"] = 2
+    loadedModel["participant_type"] = content["participant_type"] = participant_type
+
+    with pytest.raises(ValidationError, match=f"Could not find a matching time dataset for the provided participant_type: {participant_type}. Found Time Datasets:"):
+        InputValidationTimes.check_user_belongs_to_same_group_as_dataset_determines(user_data, loadedModel=loadedModel, times_id=None)
+
+    # fails: participant type 2 exists, but user_id 2 is part of the wrong participant_id group (user_id 28 or 29 would be)
+    user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=2)
+    loadedModel["shipcall_id"] = content["shipcall_id"] = 222
+    participant_type = 2
+    loadedModel["participant_type"] = content["participant_type"] = participant_type
+    with pytest.raises(ValidationError, match="The dataset may only be changed by a user belonging to the same participant group as the times dataset is referring to. User participant_id:"):
+        InputValidationTimes.check_user_belongs_to_same_group_as_dataset_determines(user_data, loadedModel=loadedModel, times_id=None)
+
+    # pass: participant type 2 exists & user_id is part of participant_id group 136, which is correct
+    user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=28)
+    loadedModel["shipcall_id"] = content["shipcall_id"] = 222
+    participant_type = 2
+    loadedModel["participant_type"] = content["participant_type"] = participant_type
+    InputValidationTimes.check_user_belongs_to_same_group_as_dataset_determines(user_data, loadedModel=loadedModel, times_id=None)
+    return
+
+
+def test_input_validation_times_put_request_fails_when_id_field_is_missing():
+    """used within PUT-requests. When 'id' is missing, a ValidationError is issued"""
+    # passes: as an 'id' is provided
+    user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=3)
+    content["id"] = 379
+    InputValidationTimes.check_times_required_fields_put_data(content)
+
+    # fails: 'id' field is missing
+    user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=3)
+    content.pop("id",None)
+    with pytest.raises(ValidationError, match="A PUT-request requires an 'id' reference, which was not found."):
+        InputValidationTimes.check_times_required_fields_put_data(content)
+    return
+
+def test_input_validation_times_delete_request_fails_when_times_id_is_deleted_already():
+    # passes: id exists
+    times_id = 379
+    InputValidationTimes.check_if_entry_is_already_deleted(times_id)
+
+    # passes: id exists
+    times_id = 391
+    InputValidationTimes.check_if_entry_is_already_deleted(times_id)
+
+    # fails
+    times_id = 11
+    with pytest.raises(ValidationError, match=f"The selected time entry is already deleted. ID: {times_id}"):
+        InputValidationTimes.check_if_entry_is_already_deleted(times_id)
+
+    # fails
+    times_id = 4
+    with pytest.raises(ValidationError, match=f"The selected time entry is already deleted. ID: {times_id}"):
+        InputValidationTimes.check_if_entry_is_already_deleted(times_id)
+    return
+
+def test_input_validation_times_delete_request_fails_when_times_id_does_not_exist_():
+    # passes: times_id exists
+    user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=28)
+    times_id = 392
+    InputValidationTimes.check_user_belongs_to_same_group_as_dataset_determines(user_data, loadedModel=None, times_id=times_id)
+
+    # fails: times_id does not exist
+    user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=28)
+    times_id = 4
+    with pytest.raises(ValidationError, match=f"Unknown times_id. Could not find a matching entry for ID: {times_id}"):
+        InputValidationTimes.check_user_belongs_to_same_group_as_dataset_determines(user_data, loadedModel=None, times_id=times_id)
+    return
+
+def test_input_validation_times_delete_request_fails_when_user_belongs_to_wrong_participant_id():
+    # fails: participant_id should be 136, but user_id=3 belongs to participant_id=2
+    user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=3)
+    times_id = 392
+
+    with pytest.raises(ValidationError, match=f"The dataset may only be changed by a user belonging to the same participant group as the times dataset is referring to. User participant_id:"):
+        InputValidationTimes.check_user_belongs_to_same_group_as_dataset_determines(user_data, loadedModel=None, times_id=times_id)
+
+    # passes: participant_id should be 136, and user_id=28 belongs to participant_id=2
+    user_data, loadedModel, content = get_valid_stub_for_pytests(user_id=28)
+    times_id = 392
+    InputValidationTimes.check_user_belongs_to_same_group_as_dataset_determines(user_data, loadedModel=None, times_id=times_id)
+    return
+
+
diff --git a/src/server/tests/validators/test_validation_rule_functions.py b/src/server/tests/validators/test_validation_rule_functions.py
index fdd8152..e928474 100644
--- a/src/server/tests/validators/test_validation_rule_functions.py
+++ b/src/server/tests/validators/test_validation_rule_functions.py
@@ -12,7 +12,17 @@ from BreCal.stubs.df_times import get_df_times, random_time_perturbation, get_df
 @pytest.fixture(scope="session")
 def build_sql_proxy_connection():
     import mysql.connector
-    conn_from_pool = mysql.connector.connect(**{'host':'localhost', 'port':3306, 'user':'root', 'password':'HalloWach_2323XXL!!', 'pool_name':'brecal_pool', 'pool_size':20, 'database':'bremen_calling', 'autocommit': True})
+    import os
+    import json
+    connection_data_path = os.path.join(os.path.expanduser("~"),"secure","connection_data_local.json")
+    assert os.path.exists(connection_data_path)
+
+    with open(connection_data_path, "r") as jr:
+       connection_data = json.load(jr)
+       connection_data = {k:v for k,v in connection_data.items() if k in ["host", "port", "user", "password", "pool_size", "pool_name", "database"]}
+       
+    conn_from_pool = mysql.connector.connect(**connection_data)
+    #conn_from_pool = mysql.connector.connect(**{'host':'localhost', 'port':3306, 'user':'root', 'password':'HalloWach_2323XXL!!', 'pool_name':'brecal_pool', 'pool_size':20, 'database':'bremen_calling_local', 'autocommit': True})
     sql_handler = SQLHandler(sql_connection=conn_from_pool, read_all=True)
     vr = ValidationRules(sql_handler)
     return locals()
@@ -654,6 +664,9 @@ def test_validation_rule_fct_missing_time_tug_berth_etd__shipcall_soon_but_parti
 def test_validation_rule_fct_missing_time_terminal_berth_eta__shipcall_soon_but_participant_estimated_time_undefined(build_sql_proxy_connection):
     """0001-L validation_rule_fct_missing_time_terminal_berth_eta"""
     vr = build_sql_proxy_connection['vr']
+    import copy
+    reset_to_default = copy.deepcopy(vr.ignore_terminal_flag)
+    vr.ignore_terminal_flag = False
 
     shipcall = get_shipcall_simple()
     df_times = get_df_times(shipcall)
@@ -684,6 +697,46 @@ def test_validation_rule_fct_missing_time_terminal_berth_eta__shipcall_soon_but_
 
     # expectation: green state, no msg
     assert state==StatusFlags.YELLOW, f"function should return 'yellow', because the participant did not provide a time and the shipcall takes place soon (according to the agency)"
+    vr.ignore_terminal_flag = reset_to_default
+    return
+
+def test_validation_rule_fct_missing_time_terminal_berth_eta__shipcall_soon_but_participant_estimated_time_undefined__no_violation_because_terminal_flag_is_active(build_sql_proxy_connection):
+    """0001-L validation_rule_fct_missing_time_terminal_berth_eta"""
+    vr = build_sql_proxy_connection['vr']
+    import copy
+    reset_to_default = copy.deepcopy(vr.ignore_terminal_flag)
+    vr.ignore_terminal_flag = True
+
+    shipcall = get_shipcall_simple()
+    df_times = get_df_times(shipcall)
+
+    # according to the agency, a shipcall takes place soon (ETA/ETD)
+    df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value, "eta_berth"] = datetime.datetime.now() + datetime.timedelta(minutes=ParticipantwiseTimeDelta.TERMINAL-10)
+
+    # set times agency to be undetermined
+    df_times.loc[df_times["participant_type"]==ParticipantType.TERMINAL.value, "operations_start"] = None # previously: eta_berth, which does not exist in times_terminal
+
+    # must adapt the shipcall_participant_map, so it suits the test
+    agency_participant_id = df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value, "participant_id"].iloc[0]
+    terminal_participant_id = df_times.loc[df_times["participant_type"]==ParticipantType.TERMINAL.value, "participant_id"].iloc[0]
+
+    spm = vr.sql_handler.df_dict["shipcall_participant_map"]
+    df = pd.DataFrame(
+        [
+            {"id":10001, "shipcall_id":shipcall.id, "participant_id":agency_participant_id, "type":ParticipantType.AGENCY.value, "created":pd.Timestamp(datetime.datetime.now().isoformat()), "modified":None},
+            {"id":10002, "shipcall_id":shipcall.id, "participant_id":terminal_participant_id, "type":ParticipantType.TERMINAL.value, "created":pd.Timestamp(datetime.datetime.now().isoformat()), "modified":None}
+        ]
+    )
+    df.set_index("id", inplace=True)
+    spm = pd.concat([spm, df], axis=0, ignore_index=True)
+    vr.sql_handler.df_dict["shipcall_participant_map"] = spm
+
+    # apply the validation rule
+    (state, msg) = vr.validation_rule_fct_missing_time_terminal_berth_eta(shipcall=shipcall, df_times=df_times)
+
+    # expectation: green state, no msg
+    assert state==StatusFlags.GREEN, f"function should return 'green', becaues the ignore terminal flag is active. Hence, terminal validation rules are ignored."
+    vr.ignore_terminal_flag = reset_to_default
     return
 
 
@@ -691,6 +744,9 @@ def test_validation_rule_fct_missing_time_terminal_berth_eta__shipcall_soon_but_
 def test_validation_rule_fct_missing_time_terminal_berth_etd__shipcall_soon_but_participant_estimated_time_undefined(build_sql_proxy_connection):
     """0001-M validation_rule_fct_missing_time_terminal_berth_etd"""
     vr = build_sql_proxy_connection['vr']
+    import copy
+    reset_to_default = copy.deepcopy(vr.ignore_terminal_flag)
+    vr.ignore_terminal_flag = False
 
     shipcall = get_shipcall_simple()
     shipcall.type = ShipcallType.OUTGOING.value
@@ -723,6 +779,48 @@ def test_validation_rule_fct_missing_time_terminal_berth_etd__shipcall_soon_but_
 
     # expectation: green state, no msg
     assert state==StatusFlags.YELLOW, f"function should return 'yellow', because the participant did not provide a time and the shipcall takes place soon (according to the agency)"
+    vr.ignore_terminal_flag = reset_to_default
+    return
+
+def test_validation_rule_fct_missing_time_terminal_berth_etd__shipcall_soon_but_participant_estimated_time_undefined__no_violation_because_terminal_flag_is_active(build_sql_proxy_connection):
+    """0001-M validation_rule_fct_missing_time_terminal_berth_etd"""
+    vr = build_sql_proxy_connection['vr']
+    import copy
+    reset_to_default = copy.deepcopy(vr.ignore_terminal_flag)
+    vr.ignore_terminal_flag = True
+
+    shipcall = get_shipcall_simple()
+    shipcall.type = ShipcallType.OUTGOING.value
+    df_times = get_df_times(shipcall)
+
+    # according to the agency, a shipcall takes place soon (ETA/ETD)
+    df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value, "etd_berth"] = datetime.datetime.now() + datetime.timedelta(minutes=ParticipantwiseTimeDelta.TERMINAL-10)
+
+    # set times agency to be undetermined
+    df_times.loc[df_times["participant_type"]==ParticipantType.TERMINAL.value, "operations_end"] = None  # previously: etd_berth, which does not exist in times_terminal
+
+
+    # must adapt the shipcall_participant_map, so it suits the test
+    agency_participant_id = df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value, "participant_id"].iloc[0]
+    terminal_participant_id = df_times.loc[df_times["participant_type"]==ParticipantType.TERMINAL.value, "participant_id"].iloc[0]
+
+    spm = vr.sql_handler.df_dict["shipcall_participant_map"]
+    df = pd.DataFrame(
+        [
+            {"id":10001, "shipcall_id":shipcall.id, "participant_id":agency_participant_id, "type":ParticipantType.AGENCY.value, "created":pd.Timestamp(datetime.datetime.now().isoformat()), "modified":None},
+            {"id":10002, "shipcall_id":shipcall.id, "participant_id":terminal_participant_id, "type":ParticipantType.TERMINAL.value, "created":pd.Timestamp(datetime.datetime.now().isoformat()), "modified":None}
+        ]
+    )
+    df.set_index("id", inplace=True)
+    spm = pd.concat([spm, df], axis=0, ignore_index=True)
+    vr.sql_handler.df_dict["shipcall_participant_map"] = spm
+
+    # apply the validation rule
+    (state, msg) = vr.validation_rule_fct_missing_time_terminal_berth_etd(shipcall=shipcall, df_times=df_times)
+
+    # expectation: green state, no msg
+    assert state==StatusFlags.GREEN, f"function should return 'green', becaues the ignore terminal flag is active. Hence, terminal validation rules are ignored."
+    vr.ignore_terminal_flag = reset_to_default
     return
 
 
@@ -912,6 +1010,10 @@ def test_validation_rule_fct_shipcall_shifting_participants_disagree_on_eta_or_e
 def test_validation_rule_fct_eta_time_not_in_operation_window__times_dont_match(build_sql_proxy_connection):
     """0003-A validation_rule_fct_eta_time_not_in_operation_window"""
     vr = build_sql_proxy_connection['vr']
+    import copy
+    reset_to_default = copy.deepcopy(vr.ignore_terminal_flag)
+    vr.ignore_terminal_flag = False
+
     shipcall = get_shipcall_simple()
     df_times = get_df_times(shipcall)
 
@@ -923,11 +1025,37 @@ def test_validation_rule_fct_eta_time_not_in_operation_window__times_dont_match(
 
     (code, msg) = vr.validation_rule_fct_eta_time_not_in_operation_window(shipcall, df_times)
     assert code==StatusFlags.RED, f"status flag should be 'red', because the planned operations start is BEFORE the estimated time of arrival for the shipcall"
+    vr.ignore_terminal_flag = reset_to_default
+    return
+
+def test_validation_rule_fct_eta_time_not_in_operation_window__times_dont_match__no_violation_because_terminal_flag_is_active(build_sql_proxy_connection):
+    """0003-A validation_rule_fct_eta_time_not_in_operation_window"""
+    vr = build_sql_proxy_connection['vr']
+    import copy
+    reset_to_default = copy.deepcopy(vr.ignore_terminal_flag)
+    vr.ignore_terminal_flag = True
+
+    shipcall = get_shipcall_simple()
+    df_times = get_df_times(shipcall)
+
+    t0_time = datetime.datetime.now() # reference time for easier readability
+
+    # the planned operations_start is before eta_berth (by one minute in this case)
+    df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value, "eta_berth"] = t0_time + datetime.timedelta(minutes=1)
+    df_times.loc[df_times["participant_type"]==ParticipantType.TERMINAL.value, "operations_start"] = t0_time + datetime.timedelta(minutes=0)
+
+    (code, msg) = vr.validation_rule_fct_eta_time_not_in_operation_window(shipcall, df_times)
+    assert code==StatusFlags.GREEN, f"the ignore terminal flag is active, so this validation rule is ignored. There should not be a violation"
+    vr.ignore_terminal_flag = reset_to_default
     return
 
 def test_validation_rule_fct_etd_time_not_in_operation_window__times_dont_match(build_sql_proxy_connection):
     """0003-B validation_rule_fct_etd_time_not_in_operation_window"""
     vr = build_sql_proxy_connection['vr']
+    import copy
+    reset_to_default = copy.deepcopy(vr.ignore_terminal_flag)
+    vr.ignore_terminal_flag = False
+
     shipcall = get_shipcall_simple()
     shipcall.type = ShipcallType.SHIFTING.value
     df_times = get_df_times(shipcall)
@@ -941,6 +1069,30 @@ def test_validation_rule_fct_etd_time_not_in_operation_window__times_dont_match(
 
     (code, msg) = vr.validation_rule_fct_etd_time_not_in_operation_window(shipcall, df_times)
     assert code==StatusFlags.RED, f"status flag should be 'red', because the planned operations end is AFTER the estimated time of departure for the shipcall"
+    vr.ignore_terminal_flag = reset_to_default
+    return
+
+def test_validation_rule_fct_etd_time_not_in_operation_window__times_dont_match__no_violation_because_terminal_flag_is_active(build_sql_proxy_connection):
+    """0003-B validation_rule_fct_etd_time_not_in_operation_window"""
+    vr = build_sql_proxy_connection['vr']
+    import copy
+    reset_to_default = copy.deepcopy(vr.ignore_terminal_flag)
+    vr.ignore_terminal_flag = True
+
+    shipcall = get_shipcall_simple()
+    shipcall.type = ShipcallType.SHIFTING.value
+    df_times = get_df_times(shipcall)
+
+    t0_time = datetime.datetime.now() # reference time for easier readability
+
+    # the planned operations_end is after etd_berth (by one minute in this case)
+    df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value, "etd_berth"] = t0_time + datetime.timedelta(hours=1)
+    df_times.loc[df_times["participant_type"]==ParticipantType.TERMINAL.value, "operations_end"] = t0_time+datetime.timedelta(hours=1, minutes=1)
+
+
+    (code, msg) = vr.validation_rule_fct_etd_time_not_in_operation_window(shipcall, df_times)
+    assert code==StatusFlags.GREEN, f"the ignore terminal flag is active, so this validation rule is ignored. There should not be a violation"
+    vr.ignore_terminal_flag = reset_to_default
     return
 
 def test_validation_rule_fct_eta_time_not_in_operation_window_and_validation_rule_fct_etd_time_not_in_operation_window__always_okay(build_sql_proxy_connection):