FastAPI 学习之路（二十八）使用密码和 Bearer 的简单 OAuth2

   OAuth2 规定在使用（我们打算用的）「password 流程」时，客户端/用户必须将 username 和 password 字段作为表单数据发送。我们看下在我们应该去如何实现呢。

        我们写一个登录接口，默认返回token和token_type

from fastapi import FastAPI, Depends,status,HTTPException
from pydantic import BaseModel
from typing import Optional
from fastapi.security import OAuth2PasswordBearer, OAuth2PasswordRequestForm

oauth2_scheme = OAuth2PasswordBearer(tokenUrl="token")
fake_users = {
    "leizi": {
        "username": "leizi",
        "full_name": "leizishuoceshikaifa",
        "email": "leizi@leizi.com",
        "hashed_password": "leizi",
        "disabled": False
    }
}
app = FastAPI()


def fake_hash_password(password: str):
    return password


class User(BaseModel):
    username: str
    email: Optional[str] = None
    full_name: Optional[str] = None
    disabled: Optional[bool] = None
class UserInDB(User):
    hashed_password: str

def get_user(db, username: str):
    if username in db:
        user_dict = db[username]
        return UserInDB(**user_dict)
def fake_decode_token(token):
    user = get_user(fake_users, token)
    return user


def get_current_user(token: str = Depends(oauth2_scheme)):
    user = fake_decode_token(token)
    print(user)
    if not user:
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail="Invalid authentication",
            headers={"WWW-Authenticate": "Bearer"},
        )
    return user
@app.post("/login")
def login(form_data: OAuth2PasswordRequestForm = Depends()):
#校验密码¶
# 目前我们已经从数据库中获取了用户数据，但尚未校验密码。

# 让我们首先将这些数据放入 Pydantic UserInDB 模型中。
# 永远不要保存明文密码，因此，我们将使用（伪）哈希密码系统。

# 如果密码不匹配，我们将返回同一个错误。


    user_dict = fake_users.get(form_data.username)
    print(user_dict)
    if not user_dict:
        raise HTTPException(status_code=400, detail="用户名错误")
    user = UserInDB(**user_dict)
    hashed_password = fake_hash_password(form_data.password)
    if not hashed_password == user.hashed_password:
        raise HTTPException(status_code=400, detail="密码错误 ")

    return {"access_token": user.username, "token_type": "bearer"}

@app.get("/users/me")
async def read_users_me(current_user: User = Depends(get_current_user)):
    print(current_user)
    return current_user