chore: Add type annotations

src/shop_db2/exceptions.py

@@ -2,15 +2,17 @@
 # -*- coding: utf-8 -*-
 __author__ = "g3n35i5"
 
+from typing import Optional
+
 from sqlalchemy.exc import DontWrapMixin
 
 # Base exception for all exceptions (needed for instance check)
 
 
 class ShopdbException(Exception, DontWrapMixin):
-    type: str = None
-    message: str = None
-    code: int = None
+    type: Optional[str] = None
+    message: Optional[str] = None
+    code: Optional[int] = None
 
 
 # App related exceptions.

src/shop_db2/helpers/decorators.py

@@ -3,6 +3,7 @@
 __author__ = "g3n35i5"
 
 from functools import wraps
+from typing import Any, Callable
 
 import jwt
 from flask import Response, request
@@ -12,11 +13,11 @@
 from shop_db2.models import User
 
 
-def checkIfUserIsValid(f):
+def checkIfUserIsValid(func: Callable) -> Callable:
     """This function checks whether the requested user exists, has been verified and is active.
     If this is not the case the request will be blocked.
 
-    :param f:                  Is the wrapped function.
+    :param func:               Is the wrapped function.
 
     :return:                   The wrapped function f with the additional parameter user.
 
@@ -25,8 +26,8 @@ def checkIfUserIsValid(f):
     :raises UserIsInactive:    If the user with this ID is inactive.
     """
 
-    @wraps(f)
-    def decorator(*args, **kwargs):
+    @wraps(func)
+    def decorator(*args: Any, **kwargs: Any) -> Any:
         user = User.query.filter_by(id=kwargs["user_id"]).first()
         if not user:
             raise exc.EntryNotFound()
@@ -40,17 +41,17 @@ def decorator(*args, **kwargs):
             raise exc.UserIsInactive()
 
         # If all criteria are met, the requested function can be executed.
-        return f(user, *args, **kwargs)
+        return func(user, *args, **kwargs)
 
     return decorator
 
 
-def adminRequired(f):
+def adminRequired(func: Callable) -> Callable:
     """This function checks whether a valid token is contained in the request.
     If this is not the case, or the user has no admin rights, the request
     will be blocked.
 
-    :param f:                   Is the wrapped function.
+    :param func:                Is the wrapped function.
 
     :return:                    The wrapped function f with the additional
                                 parameter admin.
@@ -64,48 +65,48 @@ def adminRequired(f):
     :raises UnauthorizedAccess: The user has no administrator privileges.
     """
 
-    @wraps(f)
-    def decorated(*args, **kwargs):
+    @wraps(func)
+    def decorated(*args: Any, **kwargs: Any) -> Any:
         # Does the request header contain a token?
         try:
             token = request.headers["token"]
-        except KeyError:
-            raise exc.UnauthorizedAccess()
+        except KeyError as error:
+            raise exc.UnauthorizedAccess() from error
 
         # Is the token valid?
         try:
             data = jwt.decode(token, app.config["SECRET_KEY"])
-        except jwt.exceptions.DecodeError:
-            raise exc.TokenIsInvalid()
-        except jwt.ExpiredSignatureError:
-            raise exc.TokenHasExpired()
+        except jwt.exceptions.DecodeError as error:
+            raise exc.TokenIsInvalid() from error
+        except jwt.ExpiredSignatureError as error:
+            raise exc.TokenHasExpired() from error
 
         # If there is no admin object in the token and does the user does have
         # admin rights?
         try:
             admin_id = data["user"]["id"]
             admin = User.query.filter(User.id == admin_id).first()
             assert admin.is_admin is True
-        except KeyError:
-            raise exc.TokenIsInvalid()
-        except AssertionError:
-            raise exc.UnauthorizedAccess()
+        except KeyError as error:
+            raise exc.TokenIsInvalid() from error
+        except AssertionError as error:
+            raise exc.UnauthorizedAccess() from error
 
         # At this point it was verified that the request comes from an
         # admin and the request is executed. In addition, the user is
         # forwarded to the following function so that the administrator
         # responsible for any changes in the database can be traced.
-        return f(admin=admin, *args, **kwargs)
+        return func(admin=admin, *args, **kwargs)
 
     return decorated
 
 
-def adminOptional(f):
+def adminOptional(func: Callable) -> Callable:
     """This function checks whether a valid token is contained in the request.
     If this is not the case, or the user has no admin rights, the following
     function returns only a part of the available data.
 
-    :param f:                Is the wrapped function.
+    :param func:             Is the wrapped function.
 
     :return:                 Returns the wrapped function f with the
                              additional parameter admin, if present.
@@ -117,56 +118,56 @@ def adminOptional(f):
                              token.
     """
 
-    @wraps(f)
-    def decorated(*args, **kwargs):
+    @wraps(func)
+    def decorated(*args: Any, **kwargs: Any) -> Any:
         # Does the request header contain a token?
         try:
             token = request.headers["token"]
         except KeyError:
-            return f(admin=None, *args, **kwargs)
+            return func(admin=None, *args, **kwargs)
 
         # Is the token valid?
         try:
             data = jwt.decode(token, app.config["SECRET_KEY"])
         except (jwt.exceptions.DecodeError, jwt.ExpiredSignatureError):
-            return f(admin=None, *args, **kwargs)
+            return func(admin=None, *args, **kwargs)
 
         # If there is no admin object in the token and does the user does have
         # admin rights?
         try:
             admin_id = data["user"]["id"]
             admin = User.query.filter(User.id == admin_id).first()
             assert admin.is_admin is True
-        except KeyError:
-            raise exc.TokenIsInvalid()
+        except KeyError as error:
+            raise exc.TokenIsInvalid() from error
         except AssertionError:
-            return f(admin=None, *args, **kwargs)
+            return func(admin=None, *args, **kwargs)
 
         # At this point it was verified that the request comes from an
         # admin and the request is executed. In addition, the user is
         # forwarded to the following function so that the administrator
         # responsible for any changes in the database can be traced.
-        return f(admin=admin, *args, **kwargs)
+        return func(admin=admin, *args, **kwargs)
 
     return decorated
 
 
-def deprecate_route(message=""):
+def deprecate_route(message: str = "") -> Callable:
     """This decorator adds a warning message to the response header when the route is marked as deprecated.
 
     :param message: The message to be added to the response header.
     """
 
-    def _decorator(func):
+    def _decorator(func: Callable) -> Callable:
         @wraps(func)
-        def _wrapper(*args, **kwargs):
+        def _wrapper(*args: Any, **kwargs: Any) -> Any:
             data = func(*args, **kwargs)
             # Case 1: Tuple with (Response object, Status code)
             if isinstance(data, tuple):
-                response: Response = data[0]
+                response = data[0]
             # Case 2: Plain response object
             elif isinstance(data, Response):
-                response: Response = data
+                response = data
             else:
                 return data
             response.headers["Warning"] = message

src/shop_db2/helpers/deposits.py

@@ -2,6 +2,8 @@
 # -*- coding: utf-8 -*-
 __author__ = "g3n35i5"
 
+from typing import Any, Dict
+
 from sqlalchemy.exc import IntegrityError
 
 import shop_db2.exceptions as exc
@@ -10,7 +12,7 @@
 from shop_db2.models import Deposit, User
 
 
-def insert_deposit(data, admin):
+def insert_deposit(data: Dict[str, Any], admin: User) -> None:
     """This help function creates a new deposit with the given data.
 
     :raises DataIsMissing:       If not all required data is available.
@@ -45,5 +47,5 @@ def insert_deposit(data, admin):
         deposit = Deposit(**data)
         deposit.admin_id = admin.id
         db.session.add(deposit)
-    except IntegrityError:
-        raise exc.CouldNotCreateEntry()
+    except IntegrityError as error:
+        raise exc.CouldNotCreateEntry() from error

src/shop_db2/helpers/errors.py

@@ -2,6 +2,8 @@
 # -*- coding: utf-8 -*-
 __author__ = "g3n35i5"
 
+from typing import Any
+
 import werkzeug.exceptions as werkzeug_exceptions
 from flask import jsonify
 
@@ -10,7 +12,7 @@
 
 
 @app.errorhandler(Exception)
-def handle_error(error):
+def handle_error(error: Exception) -> Any:
     """This wrapper catches all exceptions and, if possible, returns a user
     friendly response. Otherwise, it will raise the error
 
@@ -44,5 +46,4 @@ def handle_error(error):
     # Create, if possible, a user friendly response.
     if isinstance(error, exc.ShopdbException):
         return jsonify(result=error.type, message=error.message), error.code
-    else:  # pragma: no cover
-        raise error
+    raise error

src/shop_db2/helpers/hooks.py

@@ -7,15 +7,17 @@
 import time
 
 from flask import g, request
+from flask.wrappers import Response
 
 import shop_db2.exceptions as exc
 from shop_db2.api import app
 from shop_db2.helpers.decorators import adminOptional
+from shop_db2.models.user import User
 
 
 @app.before_request
 @adminOptional
-def before_request_hook(admin):
+def before_request_hook(admin: User) -> None:
     """This function is executed before each request is processed. Its purpose is
     to check whether the application is currently in maintenance mode. If this
     is the case, the current request is aborted and a corresponding exception
@@ -51,15 +53,17 @@ def before_request_hook(admin):
 
 
 @app.after_request
-def after_request_hook(response):
+def after_request_hook(response: Response) -> Response:
     """This functions gets executed each time a request is finished.
 
     :param response: is the response to be returned.
     :return:         The request response.
     """
     # If the app is in DEBUG mode, log the request execution time
-    if app.logger.level == logging.DEBUG:
+    if app.logger.level == logging.DEBUG:  # pylint: disable
         execution_time = datetime.timedelta(seconds=(time.time() - g.start))
-        app.logger.debug("Request execution time for '{}': {}".format(request.endpoint, execution_time))
+        app.logger.debug(  # pylint: disable
+            "Request execution time for '{}': {}".format(request.endpoint, execution_time)
+        )
 
     return response

src/shop_db2/helpers/products.py

@@ -12,7 +12,7 @@
 from shop_db2.models import Product, ProductPrice
 
 
-def _shift_date_to_begin_of_day(date):
+def _shift_date_to_begin_of_day(date: datetime.datetime) -> datetime.datetime:
     """This function moves a timestamp to the beginning of the day.
 
     :param date: Is the date to be moved.
@@ -21,7 +21,7 @@ def _shift_date_to_begin_of_day(date):
     return date.replace(hour=0, minute=0, second=0, microsecond=0)
 
 
-def _shift_date_to_end_of_day(date):
+def _shift_date_to_end_of_day(date: datetime.datetime) -> datetime.datetime:
     """This function moves a timestamp to the end of the day.
 
     :param date: Is the date to be moved.
@@ -30,7 +30,7 @@ def _shift_date_to_end_of_day(date):
     return date.replace(hour=23, minute=59, second=59, microsecond=999999)
 
 
-def _get_product_mean_price_in_time_range(product_id, start, end):
+def _get_product_mean_price_in_time_range(product_id: int, start: datetime.datetime, end: datetime.datetime) -> int:
     """This function calculates the mean price in a given range of time.
 
     :param product_id: Is the product id.