Upgrade sqlalchemy

Adapt code to prevent new warnings and errors (as of SQLAlchemy 1.4):
- Overlapping foreign key columns could be set in a conflicting way
  => This is prevented by the application logic
  => Ignore the warning by setting a `overlaps` flag
- Transaction already rolled back
  => This only happens when tests cause an `IntegrityError` on purpose
  => Filter away the corresponding warning in the fixture
- Query returns `Row` objects and not scalars
  => Add genexpr to pull out `primary_id`

src/urban_meal_delivery/db/addresses.py

@@ -58,16 +58,6 @@ class Address(meta.Base):
 
     # Relationships
     city = orm.relationship('City', back_populates='addresses')
-    _distances1 = orm.relationship(
-        'DistanceMatrix',
-        back_populates='first_address',
-        foreign_keys='[DistanceMatrix.first_address_id, DistanceMatrix.city_id]',
-    )
-    _distances2 = orm.relationship(
-        'DistanceMatrix',
-        back_populates='second_address',
-        foreign_keys='[DistanceMatrix.second_address_id, DistanceMatrix.city_id]',
-    )
     restaurants = orm.relationship('Restaurant', back_populates='address')
     orders_picked_up = orm.relationship(
         'Order',

src/urban_meal_delivery/db/addresses_addresses.py

@@ -89,13 +89,12 @@ class DistanceMatrix(meta.Base):
     # Relationships
     first_address = orm.relationship(
         'Address',
-        back_populates='_distances1',
         foreign_keys='[DistanceMatrix.first_address_id, DistanceMatrix.city_id]',
     )
     second_address = orm.relationship(
         'Address',
-        back_populates='_distances2',
         foreign_keys='[DistanceMatrix.second_address_id, DistanceMatrix.city_id]',
+        overlaps='first_address',
     )
 
     @classmethod

src/urban_meal_delivery/db/customers.py

@@ -67,11 +67,14 @@ class Customer(meta.Base):
             db.session.query(db.Address)
             .filter(
                 db.Address.id.in_(
-                    db.session.query(db.Address.primary_id)  # noqa:WPS221
-                    .join(db.Order, db.Address.id == db.Order.delivery_address_id)
-                    .filter(db.Order.customer_id == self.id)
-                    .distinct()
-                    .all(),
+                    row.primary_id
+                    for row in (
+                        db.session.query(db.Address.primary_id)  # noqa:WPS221
+                        .join(db.Order, db.Address.id == db.Order.delivery_address_id)
+                        .filter(db.Order.customer_id == self.id)
+                        .distinct()
+                        .all()
+                    )
                 ),
             )
             .all()

src/urban_meal_delivery/db/restaurants.py

@@ -45,7 +45,11 @@ class Restaurant(meta.Base):
 
     # Relationships
     address = orm.relationship('Address', back_populates='restaurants')
-    orders = orm.relationship('Order', back_populates='restaurant')
+    orders = orm.relationship(
+        'Order',
+        back_populates='restaurant',
+        overlaps='orders_picked_up,pickup_address',
+    )
 
     def __repr__(self) -> str:
         """Non-literal text representation."""
@@ -87,11 +91,16 @@ class Restaurant(meta.Base):
                 db.session.query(db.Address)
                 .filter(
                     db.Address.id.in_(
-                        db.session.query(db.Address.primary_id)  # noqa:WPS221
-                        .join(db.Order, db.Address.id == db.Order.delivery_address_id)
-                        .filter(db.Order.restaurant_id == self.id)
-                        .distinct()
-                        .all(),
+                        row.primary_id
+                        for row in (
+                            db.session.query(db.Address.primary_id)  # noqa:WPS221
+                            .join(
+                                db.Order, db.Address.id == db.Order.delivery_address_id,
+                            )
+                            .filter(db.Order.restaurant_id == self.id)
+                            .distinct()
+                            .all()
+                        )
                     ),
                 )
                 .all()