第六章 安全、认证和授权

Author: liaogx

run.py

@@ -9,7 +9,7 @@
 from starlette.exceptions import HTTPException as StarletteHTTPException
 
 from coronavirus import application
-from tutorial import app03, app04, app05
+from tutorial import app03, app04, app05, app06
 
 app = FastAPI(
     title='FastAPI Tutorial and Coronavirus Tracker API Docs',
@@ -43,6 +43,7 @@
 app.include_router(app03, prefix="/chapter03", tags=['第三章 请求参数和验证'])
 app.include_router(app04, prefix="/chapter04", tags=['第四章 响应处理和FastAPI配置'])
 app.include_router(app05, prefix="/chapter05", tags=['第五章 FastAPI的依赖注入系统'])
+app.include_router(app06, prefix="/chapter06", tags=['第六章 安全、认证和授权'])
 app.include_router(application, prefix="/coronavirus", tags=['新冠病毒疫情跟踪器API'])
 
 if __name__ == '__main__':

tutorial/__init__.py

@@ -5,3 +5,4 @@
 from .chapter03 import app03
 from .chapter04 import app04
 from .chapter05 import app05
+from .chapter06 import app06

tutorial/chapter06.py

@@ -0,0 +1,221 @@
+#!/usr/bin/python3
+# -*- coding:utf-8 -*-
+# __author__ = '__Jack__'
+
+from datetime import datetime, timedelta
+from typing import Optional
+
+from fastapi import APIRouter
+from fastapi import Depends, HTTPException, status
+from fastapi.security import OAuth2PasswordBearer, OAuth2PasswordRequestForm
+from jose import JWTError, jwt
+from passlib.context import CryptContext
+from pydantic import BaseModel
+
+app06 = APIRouter()
+
+"""OAuth2 密码模式和 FastAPI 的 OAuth2PasswordBearer"""
+oauth2_scheme = OAuth2PasswordBearer(tokenUrl="chapter06/token")  # 请求Token的URL地址 http://127.0.0.1:8000/chapter06/token
+
+
+@app06.get("/oauth2_password_bearer")
+async def oauth2_password_bearer(token: str = Depends(oauth2_scheme)):
+    return {"token": token}
+
+
+"""基于 Password 和 Bearer token 的 OAuth2 认证	"""
+
+fake_users_db = {
+    "john snow": {
+        "username": "john snow",
+        "full_name": "John Snow",
+        "email": "[email protected]",
+        "hashed_password": "fakehashedsecret",
+        "disabled": False,
+    },
+    "alice": {
+        "username": "alice",
+        "full_name": "Alice Wonderson",
+        "email": "[email protected]",
+        "hashed_password": "fakehashedsecret2",
+        "disabled": True,
+    },
+}
+
+
+def fake_hash_password(password: str):
+    return "fakehashed" + 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_db, token)
+    return user
+
+
+async def get_current_user(token: str = Depends(oauth2_scheme)):
+    user = fake_decode_token(token)
+    if not user:
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Invalid authentication credentials",
+            headers={"WWW-Authenticate": "Bearer"},  # OAuth2的规范，如果认证失败，请求头中返回“WWW-Authenticate”
+        )
+    return user
+
+
+async def get_current_active_user(current_user: User = Depends(get_current_user)):
+    if current_user.disabled:
+        raise HTTPException(status_code=400, detail="Inactive user")
+    return current_user
+
+
+@app06.post("/token")
+async def login(form_data: OAuth2PasswordRequestForm = Depends()):
+    user_dict = fake_users_db.get(form_data.username)
+    if not user_dict:
+        raise HTTPException(status_code=400, detail="Incorrect username or password")
+    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="Incorrect username or password")
+
+    return {"access_token": user.username, "token_type": "bearer"}
+
+
+@app06.get("/users/me")
+async def read_users_me(current_user: User = Depends(get_current_active_user)):
+    return current_user
+
+
+"""OAuth2 with Password (and hashing), Bearer with JWT tokens 开发基于JSON Web Tokens的认证"""
+
+fake_users_db.update({
+    "john snow": {
+        "username": "john snow",
+        "full_name": "John Snow",
+        "email": "[email protected]",
+        "hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
+        "disabled": False,
+    }
+})
+
+SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
+ALGORITHM = "HS256"
+ACCESS_TOKEN_EXPIRE_MINUTES = 30
+
+
+class Token(BaseModel):
+    access_token: str
+    token_type: str
+
+
+class TokenData(BaseModel):
+    username: Optional[str] = None
+
+
+pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
+
+oauth2_scheme = OAuth2PasswordBearer(tokenUrl="chapter06/jwt/token")
+
+
+def verify_password(plain_password, hashed_password):
+    return pwd_context.verify(plain_password, hashed_password)
+
+
+def get_password_hash(password):
+    return pwd_context.hash(password)
+
+
+def jwt_get_user(db, username: str):
+    if username in db:
+        user_dict = db[username]
+        return UserInDB(**user_dict)
+
+
+def authenticate_user(fake_db, username: str, password: str):
+    user = get_user(fake_db, username)
+    if not user:
+        return False
+    if not verify_password(password, user.hashed_password):
+        return False
+    return user
+
+
+def create_access_token(data: dict, expires_delta: Optional[timedelta] = None):
+    to_encode = data.copy()
+    if expires_delta:
+        expire = datetime.utcnow() + expires_delta
+    else:
+        expire = datetime.utcnow() + timedelta(minutes=15)
+    to_encode.update({"exp": expire})
+    encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
+    return encoded_jwt
+
+
+async def jwt_get_current_user(token: str = Depends(oauth2_scheme)):
+    credentials_exception = HTTPException(
+        status_code=status.HTTP_401_UNAUTHORIZED,
+        detail="Could not validate credentials",
+        headers={"WWW-Authenticate": "Bearer"},
+    )
+    try:
+        payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
+        username: str = payload.get("sub")
+        if username is None:
+            raise credentials_exception
+        token_data = TokenData(username=username)
+    except JWTError:
+        raise credentials_exception
+    user = get_user(fake_users_db, username=token_data.username)
+    if user is None:
+        raise credentials_exception
+    return user
+
+
+async def jwt_get_current_active_user(current_user: User = Depends(jwt_get_current_user)):
+    if current_user.disabled:
+        raise HTTPException(status_code=400, detail="Inactive user")
+    return current_user
+
+
+@app06.post("/jwt/token", response_model=Token)
+async def login_for_access_token(form_data: OAuth2PasswordRequestForm = Depends()):
+    user = authenticate_user(fake_users_db, form_data.username, form_data.password)
+    if not user:
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Incorrect username or password",
+            headers={"WWW-Authenticate": "Bearer"},
+        )
+    access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
+    access_token = create_access_token(
+        data={"sub": user.username}, expires_delta=access_token_expires
+    )
+    return {"access_token": access_token, "token_type": "bearer"}
+
+
+@app06.get("/jwt/users/me/", response_model=User)
+async def read_users_me(current_user: User = Depends(jwt_get_current_active_user)):
+    return current_user
+
+
+@app06.get("/jwt/users/me/items/")
+async def read_own_items(current_user: User = Depends(jwt_get_current_active_user)):
+    return [{"item_id": "Foo", "owner": current_user.username}]