使用 FastAPI 依赖项的 Session¶
在我们继续添加内容之前，让我们稍微改变一下我们为每个请求获取 session 的方式，以便稍后简化我们的生活。
当前 Sessions¶
到目前为止，我们一直在每个路径操作中，在一个 with 代码块中创建 session。
# Code above omitted 👆
@app.post("/heroes/", response_model=HeroPublic)
def create_hero(hero: HeroCreate):
with Session(engine) as session:
db_hero = Hero.model_validate(hero)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
# Code below omitted 👇
👀 完整文件预览
from fastapi import FastAPI, HTTPException, Query
from sqlmodel import Field, Session, SQLModel, create_engine, select
class HeroBase(SQLModel):
name: str = Field(index=True)
secret_name: str
age: int | None = Field(default=None, index=True)
class Hero(HeroBase, table=True):
id: int | None = Field(default=None, primary_key=True)
class HeroCreate(HeroBase):
pass
class HeroPublic(HeroBase):
id: int
class HeroUpdate(SQLModel):
name: str | None = None
secret_name: str | None = None
age: int | None = None
sqlite_file_name = "database.db"
sqlite_url = f"sqlite:///{sqlite_file_name}"
connect_args = {"check_same_thread": False}
engine = create_engine(sqlite_url, echo=True, connect_args=connect_args)
def create_db_and_tables():
SQLModel.metadata.create_all(engine)
app = FastAPI()
@app.on_event("startup")
def on_startup():
create_db_and_tables()
@app.post("/heroes/", response_model=HeroPublic)
def create_hero(hero: HeroCreate):
with Session(engine) as session:
db_hero = Hero.model_validate(hero)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.get("/heroes/", response_model=list[HeroPublic])
def read_heroes(offset: int = 0, limit: int = Query(default=100, le=100)):
with Session(engine) as session:
heroes = session.exec(select(Hero).offset(offset).limit(limit)).all()
return heroes
@app.get("/heroes/{hero_id}", response_model=HeroPublic)
def read_hero(hero_id: int):
with Session(engine) as session:
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
return hero
@app.patch("/heroes/{hero_id}", response_model=HeroPublic)
def update_hero(hero_id: int, hero: HeroUpdate):
with Session(engine) as session:
db_hero = session.get(Hero, hero_id)
if not db_hero:
raise HTTPException(status_code=404, detail="Hero not found")
hero_data = hero.model_dump(exclude_unset=True)
for key, value in hero_data.items():
setattr(db_hero, key, value)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.delete("/heroes/{hero_id}")
def delete_hero(hero_id: int):
with Session(engine) as session:
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
session.delete(hero)
session.commit()
return {"ok": True}
🤓 其他版本和变体
from typing import Optional
from fastapi import FastAPI, HTTPException, Query
from sqlmodel import Field, Session, SQLModel, create_engine, select
class HeroBase(SQLModel):
name: str = Field(index=True)
secret_name: str
age: Optional[int] = Field(default=None, index=True)
class Hero(HeroBase, table=True):
id: Optional[int] = Field(default=None, primary_key=True)
class HeroCreate(HeroBase):
pass
class HeroPublic(HeroBase):
id: int
class HeroUpdate(SQLModel):
name: Optional[str] = None
secret_name: Optional[str] = None
age: Optional[int] = None
sqlite_file_name = "database.db"
sqlite_url = f"sqlite:///{sqlite_file_name}"
connect_args = {"check_same_thread": False}
engine = create_engine(sqlite_url, echo=True, connect_args=connect_args)
def create_db_and_tables():
SQLModel.metadata.create_all(engine)
app = FastAPI()
@app.on_event("startup")
def on_startup():
create_db_and_tables()
@app.post("/heroes/", response_model=HeroPublic)
def create_hero(hero: HeroCreate):
with Session(engine) as session:
db_hero = Hero.model_validate(hero)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.get("/heroes/", response_model=list[HeroPublic])
def read_heroes(offset: int = 0, limit: int = Query(default=100, le=100)):
with Session(engine) as session:
heroes = session.exec(select(Hero).offset(offset).limit(limit)).all()
return heroes
@app.get("/heroes/{hero_id}", response_model=HeroPublic)
def read_hero(hero_id: int):
with Session(engine) as session:
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
return hero
@app.patch("/heroes/{hero_id}", response_model=HeroPublic)
def update_hero(hero_id: int, hero: HeroUpdate):
with Session(engine) as session:
db_hero = session.get(Hero, hero_id)
if not db_hero:
raise HTTPException(status_code=404, detail="Hero not found")
hero_data = hero.model_dump(exclude_unset=True)
for key, value in hero_data.items():
setattr(db_hero, key, value)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.delete("/heroes/{hero_id}")
def delete_hero(hero_id: int):
with Session(engine) as session:
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
session.delete(hero)
session.commit()
return {"ok": True}
from typing import List, Optional
from fastapi import FastAPI, HTTPException, Query
from sqlmodel import Field, Session, SQLModel, create_engine, select
class HeroBase(SQLModel):
name: str = Field(index=True)
secret_name: str
age: Optional[int] = Field(default=None, index=True)
class Hero(HeroBase, table=True):
id: Optional[int] = Field(default=None, primary_key=True)
class HeroCreate(HeroBase):
pass
class HeroPublic(HeroBase):
id: int
class HeroUpdate(SQLModel):
name: Optional[str] = None
secret_name: Optional[str] = None
age: Optional[int] = None
sqlite_file_name = "database.db"
sqlite_url = f"sqlite:///{sqlite_file_name}"
connect_args = {"check_same_thread": False}
engine = create_engine(sqlite_url, echo=True, connect_args=connect_args)
def create_db_and_tables():
SQLModel.metadata.create_all(engine)
app = FastAPI()
@app.on_event("startup")
def on_startup():
create_db_and_tables()
@app.post("/heroes/", response_model=HeroPublic)
def create_hero(hero: HeroCreate):
with Session(engine) as session:
db_hero = Hero.model_validate(hero)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.get("/heroes/", response_model=List[HeroPublic])
def read_heroes(offset: int = 0, limit: int = Query(default=100, le=100)):
with Session(engine) as session:
heroes = session.exec(select(Hero).offset(offset).limit(limit)).all()
return heroes
@app.get("/heroes/{hero_id}", response_model=HeroPublic)
def read_hero(hero_id: int):
with Session(engine) as session:
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
return hero
@app.patch("/heroes/{hero_id}", response_model=HeroPublic)
def update_hero(hero_id: int, hero: HeroUpdate):
with Session(engine) as session:
db_hero = session.get(Hero, hero_id)
if not db_hero:
raise HTTPException(status_code=404, detail="Hero not found")
hero_data = hero.model_dump(exclude_unset=True)
for key, value in hero_data.items():
setattr(db_hero, key, value)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.delete("/heroes/{hero_id}")
def delete_hero(hero_id: int):
with Session(engine) as session:
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
session.delete(hero)
session.commit()
return {"ok": True}
这完全没问题，但在许多用例中，我们希望使用 FastAPI 依赖项，例如，在路径操作中执行任何其他代码之前，验证客户端是否已登录并获取当前用户。
这些依赖项在测试期间也非常有用，因为我们可以轻松地替换它们，然后，例如，为我们的测试使用新的数据库，或在测试前放入一些数据等。
因此，让我们重构这些 session 以使用 FastAPI 依赖项。
创建一个 FastAPI 依赖项¶
FastAPI 依赖项非常简单，它只是一个返回值的函数。
它可以使用 yield 而不是 return，在这种情况下，FastAPI 将确保在请求完成后执行 yield 之后的所有代码。
# Code above omitted 👆
def get_session():
with Session(engine) as session:
yield session
# Code below omitted 👇
👀 完整文件预览
from fastapi import Depends, FastAPI, HTTPException, Query
from sqlmodel import Field, Session, SQLModel, create_engine, select
class HeroBase(SQLModel):
name: str = Field(index=True)
secret_name: str
age: int | None = Field(default=None, index=True)
class Hero(HeroBase, table=True):
id: int | None = Field(default=None, primary_key=True)
class HeroCreate(HeroBase):
pass
class HeroPublic(HeroBase):
id: int
class HeroUpdate(SQLModel):
name: str | None = None
secret_name: str | None = None
age: int | None = None
sqlite_file_name = "database.db"
sqlite_url = f"sqlite:///{sqlite_file_name}"
connect_args = {"check_same_thread": False}
engine = create_engine(sqlite_url, echo=True, connect_args=connect_args)
def create_db_and_tables():
SQLModel.metadata.create_all(engine)
def get_session():
with Session(engine) as session:
yield session
app = FastAPI()
@app.on_event("startup")
def on_startup():
create_db_and_tables()
@app.post("/heroes/", response_model=HeroPublic)
def create_hero(*, session: Session = Depends(get_session), hero: HeroCreate):
db_hero = Hero.model_validate(hero)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.get("/heroes/", response_model=list[HeroPublic])
def read_heroes(
*,
session: Session = Depends(get_session),
offset: int = 0,
limit: int = Query(default=100, le=100),
):
heroes = session.exec(select(Hero).offset(offset).limit(limit)).all()
return heroes
@app.get("/heroes/{hero_id}", response_model=HeroPublic)
def read_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
return hero
@app.patch("/heroes/{hero_id}", response_model=HeroPublic)
def update_hero(
*, session: Session = Depends(get_session), hero_id: int, hero: HeroUpdate
):
db_hero = session.get(Hero, hero_id)
if not db_hero:
raise HTTPException(status_code=404, detail="Hero not found")
hero_data = hero.model_dump(exclude_unset=True)
for key, value in hero_data.items():
setattr(db_hero, key, value)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.delete("/heroes/{hero_id}")
def delete_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
session.delete(hero)
session.commit()
return {"ok": True}
🤓 其他版本和变体
from typing import Optional
from fastapi import Depends, FastAPI, HTTPException, Query
from sqlmodel import Field, Session, SQLModel, create_engine, select
class HeroBase(SQLModel):
name: str = Field(index=True)
secret_name: str
age: Optional[int] = Field(default=None, index=True)
class Hero(HeroBase, table=True):
id: Optional[int] = Field(default=None, primary_key=True)
class HeroCreate(HeroBase):
pass
class HeroPublic(HeroBase):
id: int
class HeroUpdate(SQLModel):
name: Optional[str] = None
secret_name: Optional[str] = None
age: Optional[int] = None
sqlite_file_name = "database.db"
sqlite_url = f"sqlite:///{sqlite_file_name}"
connect_args = {"check_same_thread": False}
engine = create_engine(sqlite_url, echo=True, connect_args=connect_args)
def create_db_and_tables():
SQLModel.metadata.create_all(engine)
def get_session():
with Session(engine) as session:
yield session
app = FastAPI()
@app.on_event("startup")
def on_startup():
create_db_and_tables()
@app.post("/heroes/", response_model=HeroPublic)
def create_hero(*, session: Session = Depends(get_session), hero: HeroCreate):
db_hero = Hero.model_validate(hero)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.get("/heroes/", response_model=list[HeroPublic])
def read_heroes(
*,
session: Session = Depends(get_session),
offset: int = 0,
limit: int = Query(default=100, le=100),
):
heroes = session.exec(select(Hero).offset(offset).limit(limit)).all()
return heroes
@app.get("/heroes/{hero_id}", response_model=HeroPublic)
def read_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
return hero
@app.patch("/heroes/{hero_id}", response_model=HeroPublic)
def update_hero(
*, session: Session = Depends(get_session), hero_id: int, hero: HeroUpdate
):
db_hero = session.get(Hero, hero_id)
if not db_hero:
raise HTTPException(status_code=404, detail="Hero not found")
hero_data = hero.model_dump(exclude_unset=True)
for key, value in hero_data.items():
setattr(db_hero, key, value)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.delete("/heroes/{hero_id}")
def delete_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
session.delete(hero)
session.commit()
return {"ok": True}
from typing import List, Optional
from fastapi import Depends, FastAPI, HTTPException, Query
from sqlmodel import Field, Session, SQLModel, create_engine, select
class HeroBase(SQLModel):
name: str = Field(index=True)
secret_name: str
age: Optional[int] = Field(default=None, index=True)
class Hero(HeroBase, table=True):
id: Optional[int] = Field(default=None, primary_key=True)
class HeroCreate(HeroBase):
pass
class HeroPublic(HeroBase):
id: int
class HeroUpdate(SQLModel):
name: Optional[str] = None
secret_name: Optional[str] = None
age: Optional[int] = None
sqlite_file_name = "database.db"
sqlite_url = f"sqlite:///{sqlite_file_name}"
connect_args = {"check_same_thread": False}
engine = create_engine(sqlite_url, echo=True, connect_args=connect_args)
def create_db_and_tables():
SQLModel.metadata.create_all(engine)
def get_session():
with Session(engine) as session:
yield session
app = FastAPI()
@app.on_event("startup")
def on_startup():
create_db_and_tables()
@app.post("/heroes/", response_model=HeroPublic)
def create_hero(*, session: Session = Depends(get_session), hero: HeroCreate):
db_hero = Hero.model_validate(hero)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.get("/heroes/", response_model=List[HeroPublic])
def read_heroes(
*,
session: Session = Depends(get_session),
offset: int = 0,
limit: int = Query(default=100, le=100),
):
heroes = session.exec(select(Hero).offset(offset).limit(limit)).all()
return heroes
@app.get("/heroes/{hero_id}", response_model=HeroPublic)
def read_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
return hero
@app.patch("/heroes/{hero_id}", response_model=HeroPublic)
def update_hero(
*, session: Session = Depends(get_session), hero_id: int, hero: HeroUpdate
):
db_hero = session.get(Hero, hero_id)
if not db_hero:
raise HTTPException(status_code=404, detail="Hero not found")
hero_data = hero.model_dump(exclude_unset=True)
for key, value in hero_data.items():
setattr(db_hero, key, value)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.delete("/heroes/{hero_id}")
def delete_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
session.delete(hero)
session.commit()
return {"ok": True}
使用依赖项¶
现在让我们让 FastAPI 执行一个依赖项并在路径操作中获取它的值。
我们从 fastapi 导入 Depends()。然后在路径操作函数中的参数中使用它，就像我们声明参数来获取 JSON body、路径参数等一样。
from fastapi import Depends, FastAPI, HTTPException, Query
from sqlmodel import Field, Session, SQLModel, create_engine, select
# Code here omitted 👈
def get_session():
with Session(engine) as session:
yield session
# Code here omitted 👈
@app.post("/heroes/", response_model=HeroPublic)
def create_hero(*, session: Session = Depends(get_session), hero: HeroCreate):
db_hero = Hero.model_validate(hero)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
# Code below omitted 👇
👀 完整文件预览
from fastapi import Depends, FastAPI, HTTPException, Query
from sqlmodel import Field, Session, SQLModel, create_engine, select
class HeroBase(SQLModel):
name: str = Field(index=True)
secret_name: str
age: int | None = Field(default=None, index=True)
class Hero(HeroBase, table=True):
id: int | None = Field(default=None, primary_key=True)
class HeroCreate(HeroBase):
pass
class HeroPublic(HeroBase):
id: int
class HeroUpdate(SQLModel):
name: str | None = None
secret_name: str | None = None
age: int | None = None
sqlite_file_name = "database.db"
sqlite_url = f"sqlite:///{sqlite_file_name}"
connect_args = {"check_same_thread": False}
engine = create_engine(sqlite_url, echo=True, connect_args=connect_args)
def create_db_and_tables():
SQLModel.metadata.create_all(engine)
def get_session():
with Session(engine) as session:
yield session
app = FastAPI()
@app.on_event("startup")
def on_startup():
create_db_and_tables()
@app.post("/heroes/", response_model=HeroPublic)
def create_hero(*, session: Session = Depends(get_session), hero: HeroCreate):
db_hero = Hero.model_validate(hero)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.get("/heroes/", response_model=list[HeroPublic])
def read_heroes(
*,
session: Session = Depends(get_session),
offset: int = 0,
limit: int = Query(default=100, le=100),
):
heroes = session.exec(select(Hero).offset(offset).limit(limit)).all()
return heroes
@app.get("/heroes/{hero_id}", response_model=HeroPublic)
def read_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
return hero
@app.patch("/heroes/{hero_id}", response_model=HeroPublic)
def update_hero(
*, session: Session = Depends(get_session), hero_id: int, hero: HeroUpdate
):
db_hero = session.get(Hero, hero_id)
if not db_hero:
raise HTTPException(status_code=404, detail="Hero not found")
hero_data = hero.model_dump(exclude_unset=True)
for key, value in hero_data.items():
setattr(db_hero, key, value)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.delete("/heroes/{hero_id}")
def delete_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
session.delete(hero)
session.commit()
return {"ok": True}
🤓 其他版本和变体
from typing import Optional
from fastapi import Depends, FastAPI, HTTPException, Query
from sqlmodel import Field, Session, SQLModel, create_engine, select
class HeroBase(SQLModel):
name: str = Field(index=True)
secret_name: str
age: Optional[int] = Field(default=None, index=True)
class Hero(HeroBase, table=True):
id: Optional[int] = Field(default=None, primary_key=True)
class HeroCreate(HeroBase):
pass
class HeroPublic(HeroBase):
id: int
class HeroUpdate(SQLModel):
name: Optional[str] = None
secret_name: Optional[str] = None
age: Optional[int] = None
sqlite_file_name = "database.db"
sqlite_url = f"sqlite:///{sqlite_file_name}"
connect_args = {"check_same_thread": False}
engine = create_engine(sqlite_url, echo=True, connect_args=connect_args)
def create_db_and_tables():
SQLModel.metadata.create_all(engine)
def get_session():
with Session(engine) as session:
yield session
app = FastAPI()
@app.on_event("startup")
def on_startup():
create_db_and_tables()
@app.post("/heroes/", response_model=HeroPublic)
def create_hero(*, session: Session = Depends(get_session), hero: HeroCreate):
db_hero = Hero.model_validate(hero)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.get("/heroes/", response_model=list[HeroPublic])
def read_heroes(
*,
session: Session = Depends(get_session),
offset: int = 0,
limit: int = Query(default=100, le=100),
):
heroes = session.exec(select(Hero).offset(offset).limit(limit)).all()
return heroes
@app.get("/heroes/{hero_id}", response_model=HeroPublic)
def read_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
return hero
@app.patch("/heroes/{hero_id}", response_model=HeroPublic)
def update_hero(
*, session: Session = Depends(get_session), hero_id: int, hero: HeroUpdate
):
db_hero = session.get(Hero, hero_id)
if not db_hero:
raise HTTPException(status_code=404, detail="Hero not found")
hero_data = hero.model_dump(exclude_unset=True)
for key, value in hero_data.items():
setattr(db_hero, key, value)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.delete("/heroes/{hero_id}")
def delete_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
session.delete(hero)
session.commit()
return {"ok": True}
from typing import List, Optional
from fastapi import Depends, FastAPI, HTTPException, Query
from sqlmodel import Field, Session, SQLModel, create_engine, select
class HeroBase(SQLModel):
name: str = Field(index=True)
secret_name: str
age: Optional[int] = Field(default=None, index=True)
class Hero(HeroBase, table=True):
id: Optional[int] = Field(default=None, primary_key=True)
class HeroCreate(HeroBase):
pass
class HeroPublic(HeroBase):
id: int
class HeroUpdate(SQLModel):
name: Optional[str] = None
secret_name: Optional[str] = None
age: Optional[int] = None
sqlite_file_name = "database.db"
sqlite_url = f"sqlite:///{sqlite_file_name}"
connect_args = {"check_same_thread": False}
engine = create_engine(sqlite_url, echo=True, connect_args=connect_args)
def create_db_and_tables():
SQLModel.metadata.create_all(engine)
def get_session():
with Session(engine) as session:
yield session
app = FastAPI()
@app.on_event("startup")
def on_startup():
create_db_and_tables()
@app.post("/heroes/", response_model=HeroPublic)
def create_hero(*, session: Session = Depends(get_session), hero: HeroCreate):
db_hero = Hero.model_validate(hero)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.get("/heroes/", response_model=List[HeroPublic])
def read_heroes(
*,
session: Session = Depends(get_session),
offset: int = 0,
limit: int = Query(default=100, le=100),
):
heroes = session.exec(select(Hero).offset(offset).limit(limit)).all()
return heroes
@app.get("/heroes/{hero_id}", response_model=HeroPublic)
def read_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
return hero
@app.patch("/heroes/{hero_id}", response_model=HeroPublic)
def update_hero(
*, session: Session = Depends(get_session), hero_id: int, hero: HeroUpdate
):
db_hero = session.get(Hero, hero_id)
if not db_hero:
raise HTTPException(status_code=404, detail="Hero not found")
hero_data = hero.model_dump(exclude_unset=True)
for key, value in hero_data.items():
setattr(db_hero, key, value)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.delete("/heroes/{hero_id}")
def delete_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
session.delete(hero)
session.commit()
return {"ok": True}
提示
这是一个关于参数中 *, 的提示。
在这里，我们传递了参数 session，它在参数 hero 之前具有 Depends(get_session) 的“默认值”，而 hero 没有任何默认值。
Python 通常会对此抱怨，但我们可以使用初始“参数” *, 将所有剩余的参数标记为“仅关键字”，这解决了问题。
您可以在 FastAPI 文档中阅读更多相关信息 路径参数和数值验证 - 根据需要排列参数，技巧
依赖项的值将仅用于一个请求，FastAPI 将在调用您的代码之前立即调用它，并为您提供来自该依赖项的值。
如果它有 yield，那么它将在您完成发送响应后继续执行其余部分。在 session 的情况下，它将完成 with 代码块中的清理代码，关闭 session 等。
然后 FastAPI 将为下一个请求再次调用它。
因为它每个请求调用一次，我们仍然会得到每个请求一个 session，正如我们应该的那样，所以我们仍然没问题。 ✅
并且由于依赖项可以使用 yield，FastAPI 将确保在完成操作后运行 yield 之后的代码，包括 with 代码块末尾的所有清理代码。所以我们也没问题。 ✅
with 代码块¶
这意味着在路径操作函数的主要代码中，它的工作方式将等同于之前带有显式 with 代码块的版本。
from fastapi import Depends, FastAPI, HTTPException, Query
from sqlmodel import Field, Session, SQLModel, create_engine, select
# Code here omitted 👈
def get_session():
with Session(engine) as session:
yield session
# Code here omitted 👈
@app.post("/heroes/", response_model=HeroPublic)
def create_hero(*, session: Session = Depends(get_session), hero: HeroCreate):
db_hero = Hero.model_validate(hero)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
# Code below omitted 👇
👀 完整文件预览
from fastapi import Depends, FastAPI, HTTPException, Query
from sqlmodel import Field, Session, SQLModel, create_engine, select
class HeroBase(SQLModel):
name: str = Field(index=True)
secret_name: str
age: int | None = Field(default=None, index=True)
class Hero(HeroBase, table=True):
id: int | None = Field(default=None, primary_key=True)
class HeroCreate(HeroBase):
pass
class HeroPublic(HeroBase):
id: int
class HeroUpdate(SQLModel):
name: str | None = None
secret_name: str | None = None
age: int | None = None
sqlite_file_name = "database.db"
sqlite_url = f"sqlite:///{sqlite_file_name}"
connect_args = {"check_same_thread": False}
engine = create_engine(sqlite_url, echo=True, connect_args=connect_args)
def create_db_and_tables():
SQLModel.metadata.create_all(engine)
def get_session():
with Session(engine) as session:
yield session
app = FastAPI()
@app.on_event("startup")
def on_startup():
create_db_and_tables()
@app.post("/heroes/", response_model=HeroPublic)
def create_hero(*, session: Session = Depends(get_session), hero: HeroCreate):
db_hero = Hero.model_validate(hero)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.get("/heroes/", response_model=list[HeroPublic])
def read_heroes(
*,
session: Session = Depends(get_session),
offset: int = 0,
limit: int = Query(default=100, le=100),
):
heroes = session.exec(select(Hero).offset(offset).limit(limit)).all()
return heroes
@app.get("/heroes/{hero_id}", response_model=HeroPublic)
def read_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
return hero
@app.patch("/heroes/{hero_id}", response_model=HeroPublic)
def update_hero(
*, session: Session = Depends(get_session), hero_id: int, hero: HeroUpdate
):
db_hero = session.get(Hero, hero_id)
if not db_hero:
raise HTTPException(status_code=404, detail="Hero not found")
hero_data = hero.model_dump(exclude_unset=True)
for key, value in hero_data.items():
setattr(db_hero, key, value)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.delete("/heroes/{hero_id}")
def delete_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
session.delete(hero)
session.commit()
return {"ok": True}
🤓 其他版本和变体
from typing import Optional
from fastapi import Depends, FastAPI, HTTPException, Query
from sqlmodel import Field, Session, SQLModel, create_engine, select
class HeroBase(SQLModel):
name: str = Field(index=True)
secret_name: str
age: Optional[int] = Field(default=None, index=True)
class Hero(HeroBase, table=True):
id: Optional[int] = Field(default=None, primary_key=True)
class HeroCreate(HeroBase):
pass
class HeroPublic(HeroBase):
id: int
class HeroUpdate(SQLModel):
name: Optional[str] = None
secret_name: Optional[str] = None
age: Optional[int] = None
sqlite_file_name = "database.db"
sqlite_url = f"sqlite:///{sqlite_file_name}"
connect_args = {"check_same_thread": False}
engine = create_engine(sqlite_url, echo=True, connect_args=connect_args)
def create_db_and_tables():
SQLModel.metadata.create_all(engine)
def get_session():
with Session(engine) as session:
yield session
app = FastAPI()
@app.on_event("startup")
def on_startup():
create_db_and_tables()
@app.post("/heroes/", response_model=HeroPublic)
def create_hero(*, session: Session = Depends(get_session), hero: HeroCreate):
db_hero = Hero.model_validate(hero)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.get("/heroes/", response_model=list[HeroPublic])
def read_heroes(
*,
session: Session = Depends(get_session),
offset: int = 0,
limit: int = Query(default=100, le=100),
):
heroes = session.exec(select(Hero).offset(offset).limit(limit)).all()
return heroes
@app.get("/heroes/{hero_id}", response_model=HeroPublic)
def read_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
return hero
@app.patch("/heroes/{hero_id}", response_model=HeroPublic)
def update_hero(
*, session: Session = Depends(get_session), hero_id: int, hero: HeroUpdate
):
db_hero = session.get(Hero, hero_id)
if not db_hero:
raise HTTPException(status_code=404, detail="Hero not found")
hero_data = hero.model_dump(exclude_unset=True)
for key, value in hero_data.items():
setattr(db_hero, key, value)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.delete("/heroes/{hero_id}")
def delete_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
session.delete(hero)
session.commit()
return {"ok": True}
from typing import List, Optional
from fastapi import Depends, FastAPI, HTTPException, Query
from sqlmodel import Field, Session, SQLModel, create_engine, select
class HeroBase(SQLModel):
name: str = Field(index=True)
secret_name: str
age: Optional[int] = Field(default=None, index=True)
class Hero(HeroBase, table=True):
id: Optional[int] = Field(default=None, primary_key=True)
class HeroCreate(HeroBase):
pass
class HeroPublic(HeroBase):
id: int
class HeroUpdate(SQLModel):
name: Optional[str] = None
secret_name: Optional[str] = None
age: Optional[int] = None
sqlite_file_name = "database.db"
sqlite_url = f"sqlite:///{sqlite_file_name}"
connect_args = {"check_same_thread": False}
engine = create_engine(sqlite_url, echo=True, connect_args=connect_args)
def create_db_and_tables():
SQLModel.metadata.create_all(engine)
def get_session():
with Session(engine) as session:
yield session
app = FastAPI()
@app.on_event("startup")
def on_startup():
create_db_and_tables()
@app.post("/heroes/", response_model=HeroPublic)
def create_hero(*, session: Session = Depends(get_session), hero: HeroCreate):
db_hero = Hero.model_validate(hero)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.get("/heroes/", response_model=List[HeroPublic])
def read_heroes(
*,
session: Session = Depends(get_session),
offset: int = 0,
limit: int = Query(default=100, le=100),
):
heroes = session.exec(select(Hero).offset(offset).limit(limit)).all()
return heroes
@app.get("/heroes/{hero_id}", response_model=HeroPublic)
def read_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
return hero
@app.patch("/heroes/{hero_id}", response_model=HeroPublic)
def update_hero(
*, session: Session = Depends(get_session), hero_id: int, hero: HeroUpdate
):
db_hero = session.get(Hero, hero_id)
if not db_hero:
raise HTTPException(status_code=404, detail="Hero not found")
hero_data = hero.model_dump(exclude_unset=True)
for key, value in hero_data.items():
setattr(db_hero, key, value)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.delete("/heroes/{hero_id}")
def delete_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
session.delete(hero)
session.commit()
return {"ok": True}
实际上，您可以认为 create_hero() 函数内部的所有代码块仍然在 session 的 with 代码块内，因为这或多或少是幕后发生的事情。
但现在，with 代码块不再显式地在函数中，而是在上面的依赖项中
from fastapi import Depends, FastAPI, HTTPException, Query
from sqlmodel import Field, Session, SQLModel, create_engine, select
# Code here omitted 👈
def get_session():
with Session(engine) as session:
yield session
# Code here omitted 👈
@app.post("/heroes/", response_model=HeroPublic)
def create_hero(*, session: Session = Depends(get_session), hero: HeroCreate):
db_hero = Hero.model_validate(hero)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
# Code below omitted 👇
👀 完整文件预览
from fastapi import Depends, FastAPI, HTTPException, Query
from sqlmodel import Field, Session, SQLModel, create_engine, select
class HeroBase(SQLModel):
name: str = Field(index=True)
secret_name: str
age: int | None = Field(default=None, index=True)
class Hero(HeroBase, table=True):
id: int | None = Field(default=None, primary_key=True)
class HeroCreate(HeroBase):
pass
class HeroPublic(HeroBase):
id: int
class HeroUpdate(SQLModel):
name: str | None = None
secret_name: str | None = None
age: int | None = None
sqlite_file_name = "database.db"
sqlite_url = f"sqlite:///{sqlite_file_name}"
connect_args = {"check_same_thread": False}
engine = create_engine(sqlite_url, echo=True, connect_args=connect_args)
def create_db_and_tables():
SQLModel.metadata.create_all(engine)
def get_session():
with Session(engine) as session:
yield session
app = FastAPI()
@app.on_event("startup")
def on_startup():
create_db_and_tables()
@app.post("/heroes/", response_model=HeroPublic)
def create_hero(*, session: Session = Depends(get_session), hero: HeroCreate):
db_hero = Hero.model_validate(hero)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.get("/heroes/", response_model=list[HeroPublic])
def read_heroes(
*,
session: Session = Depends(get_session),
offset: int = 0,
limit: int = Query(default=100, le=100),
):
heroes = session.exec(select(Hero).offset(offset).limit(limit)).all()
return heroes
@app.get("/heroes/{hero_id}", response_model=HeroPublic)
def read_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
return hero
@app.patch("/heroes/{hero_id}", response_model=HeroPublic)
def update_hero(
*, session: Session = Depends(get_session), hero_id: int, hero: HeroUpdate
):
db_hero = session.get(Hero, hero_id)
if not db_hero:
raise HTTPException(status_code=404, detail="Hero not found")
hero_data = hero.model_dump(exclude_unset=True)
for key, value in hero_data.items():
setattr(db_hero, key, value)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.delete("/heroes/{hero_id}")
def delete_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
session.delete(hero)
session.commit()
return {"ok": True}
🤓 其他版本和变体
from typing import Optional
from fastapi import Depends, FastAPI, HTTPException, Query
from sqlmodel import Field, Session, SQLModel, create_engine, select
class HeroBase(SQLModel):
name: str = Field(index=True)
secret_name: str
age: Optional[int] = Field(default=None, index=True)
class Hero(HeroBase, table=True):
id: Optional[int] = Field(default=None, primary_key=True)
class HeroCreate(HeroBase):
pass
class HeroPublic(HeroBase):
id: int
class HeroUpdate(SQLModel):
name: Optional[str] = None
secret_name: Optional[str] = None
age: Optional[int] = None
sqlite_file_name = "database.db"
sqlite_url = f"sqlite:///{sqlite_file_name}"
connect_args = {"check_same_thread": False}
engine = create_engine(sqlite_url, echo=True, connect_args=connect_args)
def create_db_and_tables():
SQLModel.metadata.create_all(engine)
def get_session():
with Session(engine) as session:
yield session
app = FastAPI()
@app.on_event("startup")
def on_startup():
create_db_and_tables()
@app.post("/heroes/", response_model=HeroPublic)
def create_hero(*, session: Session = Depends(get_session), hero: HeroCreate):
db_hero = Hero.model_validate(hero)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.get("/heroes/", response_model=list[HeroPublic])
def read_heroes(
*,
session: Session = Depends(get_session),
offset: int = 0,
limit: int = Query(default=100, le=100),
):
heroes = session.exec(select(Hero).offset(offset).limit(limit)).all()
return heroes
@app.get("/heroes/{hero_id}", response_model=HeroPublic)
def read_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
return hero
@app.patch("/heroes/{hero_id}", response_model=HeroPublic)
def update_hero(
*, session: Session = Depends(get_session), hero_id: int, hero: HeroUpdate
):
db_hero = session.get(Hero, hero_id)
if not db_hero:
raise HTTPException(status_code=404, detail="Hero not found")
hero_data = hero.model_dump(exclude_unset=True)
for key, value in hero_data.items():
setattr(db_hero, key, value)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.delete("/heroes/{hero_id}")
def delete_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
session.delete(hero)
session.commit()
return {"ok": True}
from typing import List, Optional
from fastapi import Depends, FastAPI, HTTPException, Query
from sqlmodel import Field, Session, SQLModel, create_engine, select
class HeroBase(SQLModel):
name: str = Field(index=True)
secret_name: str
age: Optional[int] = Field(default=None, index=True)
class Hero(HeroBase, table=True):
id: Optional[int] = Field(default=None, primary_key=True)
class HeroCreate(HeroBase):
pass
class HeroPublic(HeroBase):
id: int
class HeroUpdate(SQLModel):
name: Optional[str] = None
secret_name: Optional[str] = None
age: Optional[int] = None
sqlite_file_name = "database.db"
sqlite_url = f"sqlite:///{sqlite_file_name}"
connect_args = {"check_same_thread": False}
engine = create_engine(sqlite_url, echo=True, connect_args=connect_args)
def create_db_and_tables():
SQLModel.metadata.create_all(engine)
def get_session():
with Session(engine) as session:
yield session
app = FastAPI()
@app.on_event("startup")
def on_startup():
create_db_and_tables()
@app.post("/heroes/", response_model=HeroPublic)
def create_hero(*, session: Session = Depends(get_session), hero: HeroCreate):
db_hero = Hero.model_validate(hero)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.get("/heroes/", response_model=List[HeroPublic])
def read_heroes(
*,
session: Session = Depends(get_session),
offset: int = 0,
limit: int = Query(default=100, le=100),
):
heroes = session.exec(select(Hero).offset(offset).limit(limit)).all()
return heroes
@app.get("/heroes/{hero_id}", response_model=HeroPublic)
def read_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
return hero
@app.patch("/heroes/{hero_id}", response_model=HeroPublic)
def update_hero(
*, session: Session = Depends(get_session), hero_id: int, hero: HeroUpdate
):
db_hero = session.get(Hero, hero_id)
if not db_hero:
raise HTTPException(status_code=404, detail="Hero not found")
hero_data = hero.model_dump(exclude_unset=True)
for key, value in hero_data.items():
setattr(db_hero, key, value)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.delete("/heroes/{hero_id}")
def delete_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
session.delete(hero)
session.commit()
return {"ok": True}
我们将看到这在稍后测试代码时非常有用。 ✅
更新路径操作以使用依赖项¶
现在我们可以更新其余的路径操作以使用新的依赖项。
我们只需在函数的参数中声明依赖项，使用
session: Session = Depends(get_session)
然后我们移除之前带有旧 session 的 with 代码块。
from fastapi import Depends, FastAPI, HTTPException, Query
from sqlmodel import Field, Session, SQLModel, create_engine, select
# Code here omitted 👈
def get_session():
with Session(engine) as session:
yield session
# Code here omitted 👈
@app.post("/heroes/", response_model=HeroPublic)
def create_hero(*, session: Session = Depends(get_session), hero: HeroCreate):
db_hero = Hero.model_validate(hero)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.get("/heroes/", response_model=list[HeroPublic])
def read_heroes(
*,
session: Session = Depends(get_session),
offset: int = 0,
limit: int = Query(default=100, le=100),
):
heroes = session.exec(select(Hero).offset(offset).limit(limit)).all()
return heroes
@app.get("/heroes/{hero_id}", response_model=HeroPublic)
def read_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
return hero
@app.patch("/heroes/{hero_id}", response_model=HeroPublic)
def update_hero(
*, session: Session = Depends(get_session), hero_id: int, hero: HeroUpdate
):
db_hero = session.get(Hero, hero_id)
if not db_hero:
raise HTTPException(status_code=404, detail="Hero not found")
hero_data = hero.model_dump(exclude_unset=True)
for key, value in hero_data.items():
setattr(db_hero, key, value)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.delete("/heroes/{hero_id}")
def delete_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
session.delete(hero)
session.commit()
return {"ok": True}
👀 完整文件预览
from fastapi import Depends, FastAPI, HTTPException, Query
from sqlmodel import Field, Session, SQLModel, create_engine, select
class HeroBase(SQLModel):
name: str = Field(index=True)
secret_name: str
age: int | None = Field(default=None, index=True)
class Hero(HeroBase, table=True):
id: int | None = Field(default=None, primary_key=True)
class HeroCreate(HeroBase):
pass
class HeroPublic(HeroBase):
id: int
class HeroUpdate(SQLModel):
name: str | None = None
secret_name: str | None = None
age: int | None = None
sqlite_file_name = "database.db"
sqlite_url = f"sqlite:///{sqlite_file_name}"
connect_args = {"check_same_thread": False}
engine = create_engine(sqlite_url, echo=True, connect_args=connect_args)
def create_db_and_tables():
SQLModel.metadata.create_all(engine)
def get_session():
with Session(engine) as session:
yield session
app = FastAPI()
@app.on_event("startup")
def on_startup():
create_db_and_tables()
@app.post("/heroes/", response_model=HeroPublic)
def create_hero(*, session: Session = Depends(get_session), hero: HeroCreate):
db_hero = Hero.model_validate(hero)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.get("/heroes/", response_model=list[HeroPublic])
def read_heroes(
*,
session: Session = Depends(get_session),
offset: int = 0,
limit: int = Query(default=100, le=100),
):
heroes = session.exec(select(Hero).offset(offset).limit(limit)).all()
return heroes
@app.get("/heroes/{hero_id}", response_model=HeroPublic)
def read_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
return hero
@app.patch("/heroes/{hero_id}", response_model=HeroPublic)
def update_hero(
*, session: Session = Depends(get_session), hero_id: int, hero: HeroUpdate
):
db_hero = session.get(Hero, hero_id)
if not db_hero:
raise HTTPException(status_code=404, detail="Hero not found")
hero_data = hero.model_dump(exclude_unset=True)
for key, value in hero_data.items():
setattr(db_hero, key, value)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.delete("/heroes/{hero_id}")
def delete_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
session.delete(hero)
session.commit()
return {"ok": True}
🤓 其他版本和变体
from typing import Optional
from fastapi import Depends, FastAPI, HTTPException, Query
from sqlmodel import Field, Session, SQLModel, create_engine, select
class HeroBase(SQLModel):
name: str = Field(index=True)
secret_name: str
age: Optional[int] = Field(default=None, index=True)
class Hero(HeroBase, table=True):
id: Optional[int] = Field(default=None, primary_key=True)
class HeroCreate(HeroBase):
pass
class HeroPublic(HeroBase):
id: int
class HeroUpdate(SQLModel):
name: Optional[str] = None
secret_name: Optional[str] = None
age: Optional[int] = None
sqlite_file_name = "database.db"
sqlite_url = f"sqlite:///{sqlite_file_name}"
connect_args = {"check_same_thread": False}
engine = create_engine(sqlite_url, echo=True, connect_args=connect_args)
def create_db_and_tables():
SQLModel.metadata.create_all(engine)
def get_session():
with Session(engine) as session:
yield session
app = FastAPI()
@app.on_event("startup")
def on_startup():
create_db_and_tables()
@app.post("/heroes/", response_model=HeroPublic)
def create_hero(*, session: Session = Depends(get_session), hero: HeroCreate):
db_hero = Hero.model_validate(hero)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.get("/heroes/", response_model=list[HeroPublic])
def read_heroes(
*,
session: Session = Depends(get_session),
offset: int = 0,
limit: int = Query(default=100, le=100),
):
heroes = session.exec(select(Hero).offset(offset).limit(limit)).all()
return heroes
@app.get("/heroes/{hero_id}", response_model=HeroPublic)
def read_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
return hero
@app.patch("/heroes/{hero_id}", response_model=HeroPublic)
def update_hero(
*, session: Session = Depends(get_session), hero_id: int, hero: HeroUpdate
):
db_hero = session.get(Hero, hero_id)
if not db_hero:
raise HTTPException(status_code=404, detail="Hero not found")
hero_data = hero.model_dump(exclude_unset=True)
for key, value in hero_data.items():
setattr(db_hero, key, value)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.delete("/heroes/{hero_id}")
def delete_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
session.delete(hero)
session.commit()
return {"ok": True}
from typing import List, Optional
from fastapi import Depends, FastAPI, HTTPException, Query
from sqlmodel import Field, Session, SQLModel, create_engine, select
class HeroBase(SQLModel):
name: str = Field(index=True)
secret_name: str
age: Optional[int] = Field(default=None, index=True)
class Hero(HeroBase, table=True):
id: Optional[int] = Field(default=None, primary_key=True)
class HeroCreate(HeroBase):
pass
class HeroPublic(HeroBase):
id: int
class HeroUpdate(SQLModel):
name: Optional[str] = None
secret_name: Optional[str] = None
age: Optional[int] = None
sqlite_file_name = "database.db"
sqlite_url = f"sqlite:///{sqlite_file_name}"
connect_args = {"check_same_thread": False}
engine = create_engine(sqlite_url, echo=True, connect_args=connect_args)
def create_db_and_tables():
SQLModel.metadata.create_all(engine)
def get_session():
with Session(engine) as session:
yield session
app = FastAPI()
@app.on_event("startup")
def on_startup():
create_db_and_tables()
@app.post("/heroes/", response_model=HeroPublic)
def create_hero(*, session: Session = Depends(get_session), hero: HeroCreate):
db_hero = Hero.model_validate(hero)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.get("/heroes/", response_model=List[HeroPublic])
def read_heroes(
*,
session: Session = Depends(get_session),
offset: int = 0,
limit: int = Query(default=100, le=100),
):
heroes = session.exec(select(Hero).offset(offset).limit(limit)).all()
return heroes
@app.get("/heroes/{hero_id}", response_model=HeroPublic)
def read_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
return hero
@app.patch("/heroes/{hero_id}", response_model=HeroPublic)
def update_hero(
*, session: Session = Depends(get_session), hero_id: int, hero: HeroUpdate
):
db_hero = session.get(Hero, hero_id)
if not db_hero:
raise HTTPException(status_code=404, detail="Hero not found")
hero_data = hero.model_dump(exclude_unset=True)
for key, value in hero_data.items():
setattr(db_hero, key, value)
session.add(db_hero)
session.commit()
session.refresh(db_hero)
return db_hero
@app.delete("/heroes/{hero_id}")
def delete_hero(*, session: Session = Depends(get_session), hero_id: int):
hero = session.get(Hero, hero_id)
if not hero:
raise HTTPException(status_code=404, detail="Hero not found")
session.delete(hero)
session.commit()
return {"ok": True}
回顾¶
您刚刚学习了如何使用 FastAPI 依赖项来处理数据库 session。这将在稍后测试代码时派上用场。
您将看到，当您更多地使用 FastAPI 时，这些依赖项可以为您提供多大的帮助，以处理权限、身份验证、数据库 sessions 等资源。 🚀
如果您想了解更多关于依赖项的信息，请查看 关于依赖项的 FastAPI 文档。