✨ Implement support for Pydantic's ORM mode (#322)

* ✨ Implement support for Pydantic's ORM mode

* 🏗️ Re-structure/augment SQL tutorial source using ORM mode

* 📝 Update SQL docs with SQLAlchemy, ORM mode, relationships

* 🔥 Remove unused util in tutorial

* 📝 Add tutorials for simple dict bodies and responses

* 🔥 Remove old SQL tutorial

* ✅ Add/update tests for SQL tutorial

* ✅ Add tests for simple dicts (body and response)

* 🐛 Fix cloning field from original field

docs/src/sql_databases/sql_app/crud.py

@@ -0,0 +1,36 @@
+from sqlalchemy.orm import Session
+
+from . import models, schemas
+
+
+def get_user(db: Session, user_id: int):
+    return db.query(models.User).filter(models.User.id == user_id).first()
+
+
+def get_user_by_email(db: Session, email: str):
+    return db.query(models.User).filter(models.User.email == email).first()
+
+
+def get_users(db: Session, skip: int = 0, limit: int = 100):
+    return db.query(models.User).offset(skip).limit(limit).all()
+
+
+def create_user(db: Session, user: schemas.UserCreate):
+    fake_hashed_password = user.password + "notreallyhashed"
+    db_user = models.User(email=user.email, hashed_password=fake_hashed_password)
+    db.add(db_user)
+    db.commit()
+    db.refresh(db_user)
+    return db_user
+
+
+def get_items(db: Session, skip: int = 0, limit: int = 100):
+    return db.query(models.Item).offset(skip).limit(limit).all()
+
+
+def create_user_item(db: Session, item: schemas.ItemCreate, user_id: int):
+    db_item = models.Item(**item.dict(), owner_id=user_id)
+    db.add(db_item)
+    db.commit()
+    db.refresh(db_item)
+    return db_item

docs/src/sql_databases/sql_app/database.py

@@ -0,0 +1,13 @@
+from sqlalchemy import create_engine
+from sqlalchemy.ext.declarative import declarative_base
+from sqlalchemy.orm import sessionmaker
+
+SQLALCHEMY_DATABASE_URI = "sqlite:///./test.db"
+# SQLALCHEMY_DATABASE_URI = "postgresql://user:password@postgresserver/db"
+
+engine = create_engine(
+    SQLALCHEMY_DATABASE_URI, connect_args={"check_same_thread": False}
+)
+SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
+
+Base = declarative_base()

docs/src/sql_databases/sql_app/main.py

@@ -0,0 +1,64 @@
+from typing import List
+
+from fastapi import Depends, FastAPI, HTTPException
+from sqlalchemy.orm import Session
+from starlette.requests import Request
+from starlette.responses import Response
+
+from . import crud, models, schemas
+from .database import SessionLocal, engine
+
+models.Base.metadata.create_all(bind=engine)
+
+app = FastAPI()
+
+
+@app.middleware("http")
+async def db_session_middleware(request: Request, call_next):
+    response = Response("Internal server error", status_code=500)
+    try:
+        request.state.db = SessionLocal()
+        response = await call_next(request)
+    finally:
+        request.state.db.close()
+    return response
+
+
+# Dependency
+def get_db(request: Request):
+    return request.state.db
+
+
+@app.post("/users/", response_model=schemas.User)
+def create_user(user: schemas.UserCreate, db: Session = Depends(get_db)):
+    db_user = crud.get_user_by_email(db, email=user.email)
+    if db_user:
+        raise HTTPException(status_code=400, detail="Email already registered")
+    return crud.create_user(db=db, user=user)
+
+
+@app.get("/users/", response_model=List[schemas.User])
+def read_users(skip: int = 0, limit: int = 100, db: Session = Depends(get_db)):
+    users = crud.get_users(db, skip=skip, limit=limit)
+    return users
+
+
+@app.get("/users/{user_id}", response_model=schemas.User)
+def read_user(user_id: int, db: Session = Depends(get_db)):
+    db_user = crud.get_user(db, user_id=user_id)
+    if db_user is None:
+        raise HTTPException(status_code=404, detail="User not found")
+    return db_user
+
+
+@app.post("/users/{user_id}/items/", response_model=schemas.Item)
+def create_item_for_user(
+    user_id: int, item: schemas.ItemCreate, db: Session = Depends(get_db)
+):
+    return crud.create_user_item(db=db, item=item, user_id=user_id)
+
+
+@app.get("/items/", response_model=List[schemas.Item])
+def read_items(skip: int = 0, limit: int = 100, db: Session = Depends(get_db)):
+    items = crud.get_items(db, skip=skip, limit=limit)
+    return items

docs/src/sql_databases/sql_app/models.py

@@ -0,0 +1,26 @@
+from sqlalchemy import Boolean, Column, ForeignKey, Integer, String
+from sqlalchemy.orm import relationship
+
+from .database import Base
+
+
+class User(Base):
+    __tablename__ = "users"
+
+    id = Column(Integer, primary_key=True, index=True)
+    email = Column(String, unique=True, index=True)
+    hashed_password = Column(String)
+    is_active = Column(Boolean, default=True)
+
+    items = relationship("Item", back_populates="owner")
+
+
+class Item(Base):
+    __tablename__ = "items"
+
+    id = Column(Integer, primary_key=True, index=True)
+    title = Column(String, index=True)
+    description = Column(String, index=True)
+    owner_id = Column(Integer, ForeignKey("users.id"))
+
+    owner = relationship("User", back_populates="items")

docs/src/sql_databases/sql_app/schemas.py

@@ -0,0 +1,37 @@
+from typing import List
+
+from pydantic import BaseModel
+
+
+class ItemBase(BaseModel):
+    title: str
+    description: str = None
+
+
+class ItemCreate(ItemBase):
+    pass
+
+
+class Item(ItemBase):
+    id: int
+    owner_id: int
+
+    class Config:
+        orm_mode = True
+
+
+class UserBase(BaseModel):
+    email: str
+
+
+class UserCreate(UserBase):
+    password: str
+
+
+class User(UserBase):
+    id: int
+    is_active: bool
+    items: List[Item] = []
+
+    class Config:
+        orm_mode = True