✨ Add Items (crud, models, endpoints), utils, refactor (#14)

* Update CRUD utils to use types better.
* Simplify Pydantic model names, from `UserInCreate` to `UserCreate`, etc.
* Upgrade packages.
* Add new generic "Items" models, crud utils, endpoints, and tests. To facilitate re-using them to create new functionality. As they are simple and generic (not like Users), it's easier to copy-paste and adapt them to each use case.
* Update endpoints/*path operations* to simplify code and use new utilities, prefix and tags in `include_router`.
* Update testing utils.
* Update linting rules, relax vulture to reduce false positives.
* Update migrations to include new Items.
* Update project README.md with tips about how to start with backend.

{{cookiecutter.project_slug}}/backend/app/app/crud/user.py

@@ -1,21 +1,22 @@
 from typing import List, Optional
 
 from fastapi.encoders import jsonable_encoder
+from sqlalchemy.orm import Session
 
 from app.core.security import get_password_hash, verify_password
 from app.db_models.user import User
-from app.models.user import UserInCreate, UserInUpdate
+from app.models.user import UserCreate, UserUpdate
 
 
-def get(db_session, *, user_id: int) -> Optional[User]:
+def get(db_session: Session, *, user_id: int) -> Optional[User]:
     return db_session.query(User).filter(User.id == user_id).first()
 
 
-def get_by_email(db_session, *, email: str) -> Optional[User]:
+def get_by_email(db_session: Session, *, email: str) -> Optional[User]:
     return db_session.query(User).filter(User.email == email).first()
 
 
-def authenticate(db_session, *, email: str, password: str) -> Optional[User]:
+def authenticate(db_session: Session, *, email: str, password: str) -> Optional[User]:
     user = get_by_email(db_session, email=email)
     if not user:
         return None
@@ -32,11 +33,11 @@ def is_superuser(user) -> bool:
     return user.is_superuser
 
 
-def get_multi(db_session, *, skip=0, limit=100) -> List[Optional[User]]:
+def get_multi(db_session: Session, *, skip=0, limit=100) -> List[Optional[User]]:
     return db_session.query(User).offset(skip).limit(limit).all()
 
 
-def create(db_session, *, user_in: UserInCreate) -> User:
+def create(db_session: Session, *, user_in: UserCreate) -> User:
     user = User(
         email=user_in.email,
         hashed_password=get_password_hash(user_in.password),
@@ -49,13 +50,12 @@ def create(db_session, *, user_in: UserInCreate) -> User:
     return user
 
 
-def update(db_session, *, user: User, user_in: UserInUpdate) -> User:
+def update(db_session: Session, *, user: User, user_in: UserUpdate) -> User:
     user_data = jsonable_encoder(user)
+    update_data = user_in.dict(skip_defaults=True)
     for field in user_data:
-        if field in user_in.fields:
-            value_in = getattr(user_in, field)
-            if value_in is not None:
-                setattr(user, field, value_in)
+        if field in update_data:
+            setattr(user, field, update_data[field])
     if user_in.password:
         passwordhash = get_password_hash(user_in.password)
         user.hashed_password = passwordhash