OAuth2 作用域¶
FastAPI 无缝集成 OAuth2 作用域(Scopes
),可以直接使用。
作用域是更精密的权限系统,遵循 OAuth2 标准,与 OpenAPI 应用(和 API 自动文档)集成。
OAuth2 也是脸书、谷歌、GitHub、微软、推特等第三方身份验证应用使用的机制。这些身份验证应用在用户登录应用时使用 OAuth2 提供指定权限。
脸书、谷歌、GitHub、微软、推特就是 OAuth2 作用域登录。
本章介绍如何在 FastAPI 应用中使用 OAuth2 作用域管理验证与授权。
警告
本章内容较难,刚接触 FastAPI 的新手可以跳过。
OAuth2 作用域不是必需的,没有它,您也可以处理身份验证与授权。
但 OAuth2 作用域与 API(通过 OpenAPI)及 API 文档集成地更好。
不管怎么说,FastAPI 支持在代码中使用作用域或其它安全/授权需求项。
很多情况下,OAuth2 作用域就像一把牛刀。
但如果您确定要使用作用域,或对它有兴趣,请继续阅读。
OAuth2 作用域与 OpenAPI¶
OAuth2 规范的作用域是由空格分割的字符串组成的列表。
这些字符串支持任何格式,但不能包含空格。
作用域表示的是权限。
OpenAPI 中(例如 API 文档)可以定义安全方案。
这些安全方案在使用 OAuth2 时,还可以声明和使用作用域。
作用域只是(不带空格的)字符串。
常用于声明特定安全权限,例如:
- 常见用例为,
users:read
或users:write
- 脸书和 Instagram 使用
instagram_basic
- 谷歌使用
https://www.googleapis.com/auth/drive
说明
OAuth2 中,作用域只是声明特定权限的字符串。
是否使用冒号 :
等符号,或是不是 URL 并不重要。
这些细节只是特定的实现方式。
对 OAuth2 来说,它们都只是字符串而已。
全局纵览¶
首先,快速浏览一下以下代码与用户指南中 OAuth2 实现密码哈希与 Bearer JWT 令牌验证一章中代码的区别。以下代码使用 OAuth2 作用域:
from datetime import datetime, timedelta, timezone
from typing import List, Union
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: Union[str, None] = None
scopes: List[str] = []
class User(BaseModel):
username: str
email: Union[str, None] = None
full_name: Union[str, None] = None
disabled: Union[bool, None] = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: Union[timedelta, None] = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: str = Depends(oauth2_scheme)
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: User = Security(get_current_user, scopes=["me"]),
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: OAuth2PasswordRequestForm = Depends(),
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(current_user: User = Depends(get_current_active_user)):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: User = Security(get_current_active_user, scopes=["items"]),
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: User = Depends(get_current_user)):
return {"status": "ok"}
🤓 Other versions and variants
from datetime import datetime, timedelta, timezone
from typing import Annotated
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: str | None = None
scopes: list[str] = []
class User(BaseModel):
username: str
email: str | None = None
full_name: str | None = None
disabled: bool | None = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: timedelta | None = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: Annotated[str, Depends(oauth2_scheme)]
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: Annotated[User, Security(get_current_user, scopes=["me"])],
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: Annotated[OAuth2PasswordRequestForm, Depends()],
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(
current_user: Annotated[User, Depends(get_current_active_user)],
):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: Annotated[User, Security(get_current_active_user, scopes=["items"])],
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: Annotated[User, Depends(get_current_user)]):
return {"status": "ok"}
from datetime import datetime, timedelta, timezone
from typing import Annotated, List, Union
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: Union[str, None] = None
scopes: List[str] = []
class User(BaseModel):
username: str
email: Union[str, None] = None
full_name: Union[str, None] = None
disabled: Union[bool, None] = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: Union[timedelta, None] = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: Annotated[str, Depends(oauth2_scheme)]
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: Annotated[User, Security(get_current_user, scopes=["me"])],
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: Annotated[OAuth2PasswordRequestForm, Depends()],
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(
current_user: Annotated[User, Depends(get_current_active_user)],
):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: Annotated[User, Security(get_current_active_user, scopes=["items"])],
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: Annotated[User, Depends(get_current_user)]):
return {"status": "ok"}
from datetime import datetime, timedelta, timezone
from typing import List, Union
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
from typing_extensions import Annotated
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: Union[str, None] = None
scopes: List[str] = []
class User(BaseModel):
username: str
email: Union[str, None] = None
full_name: Union[str, None] = None
disabled: Union[bool, None] = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: Union[timedelta, None] = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: Annotated[str, Depends(oauth2_scheme)]
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: Annotated[User, Security(get_current_user, scopes=["me"])],
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: Annotated[OAuth2PasswordRequestForm, Depends()],
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(
current_user: Annotated[User, Depends(get_current_active_user)],
):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: Annotated[User, Security(get_current_active_user, scopes=["items"])],
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: Annotated[User, Depends(get_current_user)]):
return {"status": "ok"}
Tip
Prefer to use the Annotated
version if possible.
from datetime import datetime, timedelta, timezone
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: str | None = None
scopes: list[str] = []
class User(BaseModel):
username: str
email: str | None = None
full_name: str | None = None
disabled: bool | None = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: timedelta | None = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: str = Depends(oauth2_scheme)
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: User = Security(get_current_user, scopes=["me"]),
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: OAuth2PasswordRequestForm = Depends(),
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(current_user: User = Depends(get_current_active_user)):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: User = Security(get_current_active_user, scopes=["items"]),
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: User = Depends(get_current_user)):
return {"status": "ok"}
Tip
Prefer to use the Annotated
version if possible.
from datetime import datetime, timedelta, timezone
from typing import Union
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: Union[str, None] = None
scopes: list[str] = []
class User(BaseModel):
username: str
email: Union[str, None] = None
full_name: Union[str, None] = None
disabled: Union[bool, None] = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: Union[timedelta, None] = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: str = Depends(oauth2_scheme)
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: User = Security(get_current_user, scopes=["me"]),
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: OAuth2PasswordRequestForm = Depends(),
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(current_user: User = Depends(get_current_active_user)):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: User = Security(get_current_active_user, scopes=["items"]),
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: User = Depends(get_current_user)):
return {"status": "ok"}
下面,我们逐步说明修改的代码内容。
OAuth2 安全方案¶
第一个修改的地方是,使用两个作用域 me
和 items
声明 OAuth2 安全方案。
scopes
参数接收字典,键是作用域、值是作用域的描述:
from datetime import datetime, timedelta, timezone
from typing import List, Union
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: Union[str, None] = None
scopes: List[str] = []
class User(BaseModel):
username: str
email: Union[str, None] = None
full_name: Union[str, None] = None
disabled: Union[bool, None] = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: Union[timedelta, None] = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: str = Depends(oauth2_scheme)
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: User = Security(get_current_user, scopes=["me"]),
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: OAuth2PasswordRequestForm = Depends(),
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(current_user: User = Depends(get_current_active_user)):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: User = Security(get_current_active_user, scopes=["items"]),
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: User = Depends(get_current_user)):
return {"status": "ok"}
🤓 Other versions and variants
from datetime import datetime, timedelta, timezone
from typing import Annotated
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: str | None = None
scopes: list[str] = []
class User(BaseModel):
username: str
email: str | None = None
full_name: str | None = None
disabled: bool | None = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: timedelta | None = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: Annotated[str, Depends(oauth2_scheme)]
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: Annotated[User, Security(get_current_user, scopes=["me"])],
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: Annotated[OAuth2PasswordRequestForm, Depends()],
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(
current_user: Annotated[User, Depends(get_current_active_user)],
):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: Annotated[User, Security(get_current_active_user, scopes=["items"])],
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: Annotated[User, Depends(get_current_user)]):
return {"status": "ok"}
from datetime import datetime, timedelta, timezone
from typing import Annotated, List, Union
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: Union[str, None] = None
scopes: List[str] = []
class User(BaseModel):
username: str
email: Union[str, None] = None
full_name: Union[str, None] = None
disabled: Union[bool, None] = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: Union[timedelta, None] = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: Annotated[str, Depends(oauth2_scheme)]
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: Annotated[User, Security(get_current_user, scopes=["me"])],
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: Annotated[OAuth2PasswordRequestForm, Depends()],
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(
current_user: Annotated[User, Depends(get_current_active_user)],
):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: Annotated[User, Security(get_current_active_user, scopes=["items"])],
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: Annotated[User, Depends(get_current_user)]):
return {"status": "ok"}
from datetime import datetime, timedelta, timezone
from typing import List, Union
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
from typing_extensions import Annotated
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: Union[str, None] = None
scopes: List[str] = []
class User(BaseModel):
username: str
email: Union[str, None] = None
full_name: Union[str, None] = None
disabled: Union[bool, None] = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: Union[timedelta, None] = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: Annotated[str, Depends(oauth2_scheme)]
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: Annotated[User, Security(get_current_user, scopes=["me"])],
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: Annotated[OAuth2PasswordRequestForm, Depends()],
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(
current_user: Annotated[User, Depends(get_current_active_user)],
):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: Annotated[User, Security(get_current_active_user, scopes=["items"])],
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: Annotated[User, Depends(get_current_user)]):
return {"status": "ok"}
Tip
Prefer to use the Annotated
version if possible.
from datetime import datetime, timedelta, timezone
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: str | None = None
scopes: list[str] = []
class User(BaseModel):
username: str
email: str | None = None
full_name: str | None = None
disabled: bool | None = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: timedelta | None = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: str = Depends(oauth2_scheme)
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: User = Security(get_current_user, scopes=["me"]),
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: OAuth2PasswordRequestForm = Depends(),
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(current_user: User = Depends(get_current_active_user)):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: User = Security(get_current_active_user, scopes=["items"]),
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: User = Depends(get_current_user)):
return {"status": "ok"}
Tip
Prefer to use the Annotated
version if possible.
from datetime import datetime, timedelta, timezone
from typing import Union
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: Union[str, None] = None
scopes: list[str] = []
class User(BaseModel):
username: str
email: Union[str, None] = None
full_name: Union[str, None] = None
disabled: Union[bool, None] = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: Union[timedelta, None] = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: str = Depends(oauth2_scheme)
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: User = Security(get_current_user, scopes=["me"]),
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: OAuth2PasswordRequestForm = Depends(),
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(current_user: User = Depends(get_current_active_user)):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: User = Security(get_current_active_user, scopes=["items"]),
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: User = Depends(get_current_user)):
return {"status": "ok"}
因为声明了作用域,所以登录或授权时会在 API 文档中显示。
此处,选择给予访问权限的作用域: me
和 items
。
这也是使用脸书、谷歌、GitHub 登录时的授权机制。
JWT 令牌作用域¶
现在,修改令牌路径操作,返回请求的作用域。
此处仍然使用 OAuth2PasswordRequestForm
。它包含类型为字符串列表的 scopes
属性,且scopes
属性中包含要在请求里接收的每个作用域。
这样,返回的 JWT 令牌中就包含了作用域。
危险
为了简明起见,本例把接收的作用域直接添加到了令牌里。
但在您的应用中,为了安全,应该只把作用域添加到确实需要作用域的用户,或预定义的用户。
from datetime import datetime, timedelta, timezone
from typing import List, Union
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: Union[str, None] = None
scopes: List[str] = []
class User(BaseModel):
username: str
email: Union[str, None] = None
full_name: Union[str, None] = None
disabled: Union[bool, None] = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: Union[timedelta, None] = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: str = Depends(oauth2_scheme)
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: User = Security(get_current_user, scopes=["me"]),
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: OAuth2PasswordRequestForm = Depends(),
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(current_user: User = Depends(get_current_active_user)):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: User = Security(get_current_active_user, scopes=["items"]),
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: User = Depends(get_current_user)):
return {"status": "ok"}
🤓 Other versions and variants
from datetime import datetime, timedelta, timezone
from typing import Annotated
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: str | None = None
scopes: list[str] = []
class User(BaseModel):
username: str
email: str | None = None
full_name: str | None = None
disabled: bool | None = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: timedelta | None = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: Annotated[str, Depends(oauth2_scheme)]
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: Annotated[User, Security(get_current_user, scopes=["me"])],
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: Annotated[OAuth2PasswordRequestForm, Depends()],
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(
current_user: Annotated[User, Depends(get_current_active_user)],
):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: Annotated[User, Security(get_current_active_user, scopes=["items"])],
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: Annotated[User, Depends(get_current_user)]):
return {"status": "ok"}
from datetime import datetime, timedelta, timezone
from typing import Annotated, List, Union
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: Union[str, None] = None
scopes: List[str] = []
class User(BaseModel):
username: str
email: Union[str, None] = None
full_name: Union[str, None] = None
disabled: Union[bool, None] = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: Union[timedelta, None] = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: Annotated[str, Depends(oauth2_scheme)]
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: Annotated[User, Security(get_current_user, scopes=["me"])],
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: Annotated[OAuth2PasswordRequestForm, Depends()],
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(
current_user: Annotated[User, Depends(get_current_active_user)],
):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: Annotated[User, Security(get_current_active_user, scopes=["items"])],
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: Annotated[User, Depends(get_current_user)]):
return {"status": "ok"}
from datetime import datetime, timedelta, timezone
from typing import List, Union
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
from typing_extensions import Annotated
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: Union[str, None] = None
scopes: List[str] = []
class User(BaseModel):
username: str
email: Union[str, None] = None
full_name: Union[str, None] = None
disabled: Union[bool, None] = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: Union[timedelta, None] = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: Annotated[str, Depends(oauth2_scheme)]
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: Annotated[User, Security(get_current_user, scopes=["me"])],
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: Annotated[OAuth2PasswordRequestForm, Depends()],
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(
current_user: Annotated[User, Depends(get_current_active_user)],
):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: Annotated[User, Security(get_current_active_user, scopes=["items"])],
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: Annotated[User, Depends(get_current_user)]):
return {"status": "ok"}
Tip
Prefer to use the Annotated
version if possible.
from datetime import datetime, timedelta, timezone
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: str | None = None
scopes: list[str] = []
class User(BaseModel):
username: str
email: str | None = None
full_name: str | None = None
disabled: bool | None = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: timedelta | None = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: str = Depends(oauth2_scheme)
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: User = Security(get_current_user, scopes=["me"]),
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: OAuth2PasswordRequestForm = Depends(),
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(current_user: User = Depends(get_current_active_user)):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: User = Security(get_current_active_user, scopes=["items"]),
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: User = Depends(get_current_user)):
return {"status": "ok"}
Tip
Prefer to use the Annotated
version if possible.
from datetime import datetime, timedelta, timezone
from typing import Union
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: Union[str, None] = None
scopes: list[str] = []
class User(BaseModel):
username: str
email: Union[str, None] = None
full_name: Union[str, None] = None
disabled: Union[bool, None] = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: Union[timedelta, None] = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: str = Depends(oauth2_scheme)
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: User = Security(get_current_user, scopes=["me"]),
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: OAuth2PasswordRequestForm = Depends(),
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(current_user: User = Depends(get_current_active_user)):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: User = Security(get_current_active_user, scopes=["items"]),
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: User = Depends(get_current_user)):
return {"status": "ok"}
在路径操作与依赖项中声明作用域¶
接下来,为路径操作 /users/me/items/
声明作用域 items
。
为此,要从 fastapi
中导入并使用 Security
。
Security
声明依赖项的方式和 Depends
一样,但 Security
还能接收作用域(字符串)列表类型的参数 scopes
。
此处使用与 Depends
相同的方式,把依赖项函数 get_current_active_user
传递给 Security
。
同时,还传递了作用域列表,本例中只传递了一个作用域:items
(此处支持传递更多作用域)。
依赖项函数 get_current_active_user
还能声明子依赖项,不仅可以使用 Depends
,也可以使用 Security
。声明子依赖项函数(get_current_user
)及更多作用域。
本例要求使用作用域 me
(还可以使用更多作用域)。
笔记
不必在不同位置添加不同的作用域。
本例使用的这种方式只是为了展示 FastAPI 如何处理在不同层级声明的作用域。
from datetime import datetime, timedelta, timezone
from typing import List, Union
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: Union[str, None] = None
scopes: List[str] = []
class User(BaseModel):
username: str
email: Union[str, None] = None
full_name: Union[str, None] = None
disabled: Union[bool, None] = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: Union[timedelta, None] = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: str = Depends(oauth2_scheme)
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: User = Security(get_current_user, scopes=["me"]),
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: OAuth2PasswordRequestForm = Depends(),
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(current_user: User = Depends(get_current_active_user)):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: User = Security(get_current_active_user, scopes=["items"]),
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: User = Depends(get_current_user)):
return {"status": "ok"}
🤓 Other versions and variants
from datetime import datetime, timedelta, timezone
from typing import Annotated
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: str | None = None
scopes: list[str] = []
class User(BaseModel):
username: str
email: str | None = None
full_name: str | None = None
disabled: bool | None = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: timedelta | None = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: Annotated[str, Depends(oauth2_scheme)]
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: Annotated[User, Security(get_current_user, scopes=["me"])],
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: Annotated[OAuth2PasswordRequestForm, Depends()],
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(
current_user: Annotated[User, Depends(get_current_active_user)],
):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: Annotated[User, Security(get_current_active_user, scopes=["items"])],
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: Annotated[User, Depends(get_current_user)]):
return {"status": "ok"}
from datetime import datetime, timedelta, timezone
from typing import Annotated, List, Union
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: Union[str, None] = None
scopes: List[str] = []
class User(BaseModel):
username: str
email: Union[str, None] = None
full_name: Union[str, None] = None
disabled: Union[bool, None] = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: Union[timedelta, None] = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: Annotated[str, Depends(oauth2_scheme)]
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: Annotated[User, Security(get_current_user, scopes=["me"])],
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: Annotated[OAuth2PasswordRequestForm, Depends()],
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(
current_user: Annotated[User, Depends(get_current_active_user)],
):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: Annotated[User, Security(get_current_active_user, scopes=["items"])],
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: Annotated[User, Depends(get_current_user)]):
return {"status": "ok"}
from datetime import datetime, timedelta, timezone
from typing import List, Union
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
from typing_extensions import Annotated
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: Union[str, None] = None
scopes: List[str] = []
class User(BaseModel):
username: str
email: Union[str, None] = None
full_name: Union[str, None] = None
disabled: Union[bool, None] = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: Union[timedelta, None] = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: Annotated[str, Depends(oauth2_scheme)]
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: Annotated[User, Security(get_current_user, scopes=["me"])],
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: Annotated[OAuth2PasswordRequestForm, Depends()],
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(
current_user: Annotated[User, Depends(get_current_active_user)],
):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: Annotated[User, Security(get_current_active_user, scopes=["items"])],
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: Annotated[User, Depends(get_current_user)]):
return {"status": "ok"}
Tip
Prefer to use the Annotated
version if possible.
from datetime import datetime, timedelta, timezone
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: str | None = None
scopes: list[str] = []
class User(BaseModel):
username: str
email: str | None = None
full_name: str | None = None
disabled: bool | None = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: timedelta | None = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: str = Depends(oauth2_scheme)
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: User = Security(get_current_user, scopes=["me"]),
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: OAuth2PasswordRequestForm = Depends(),
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(current_user: User = Depends(get_current_active_user)):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: User = Security(get_current_active_user, scopes=["items"]),
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: User = Depends(get_current_user)):
return {"status": "ok"}
Tip
Prefer to use the Annotated
version if possible.
from datetime import datetime, timedelta, timezone
from typing import Union
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: Union[str, None] = None
scopes: list[str] = []
class User(BaseModel):
username: str
email: Union[str, None] = None
full_name: Union[str, None] = None
disabled: Union[bool, None] = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: Union[timedelta, None] = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: str = Depends(oauth2_scheme)
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: User = Security(get_current_user, scopes=["me"]),
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: OAuth2PasswordRequestForm = Depends(),
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(current_user: User = Depends(get_current_active_user)):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: User = Security(get_current_active_user, scopes=["items"]),
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: User = Depends(get_current_user)):
return {"status": "ok"}
技术细节
Security
实际上是 Depends
的子类,而且只比 Depends
多一个参数。
但使用 Security
代替 Depends
,FastAPI 可以声明安全作用域,并在内部使用这些作用域,同时,使用 OpenAPI 存档 API。
但实际上,从 fastapi
导入的 Query
、Path
、Depends
、Security
等对象,只是返回特殊类的函数。
使用 SecurityScopes
¶
修改依赖项 get_current_user
。
这是上面的依赖项使用的依赖项。
这里使用的也是之前创建的 OAuth2 方案,并把它声明为依赖项:oauth2_scheme
。
该依赖项函数本身不需要作用域,因此,可以使用 Depends
和 oauth2_scheme
。不需要指定安全作用域时,不必使用 Security
。
此处还声明了从 fastapin.security
导入的 SecurityScopes
类型的特殊参数。
SecuriScopes
类与 Request
类似(Request
用于直接提取请求对象)。
from datetime import datetime, timedelta, timezone
from typing import List, Union
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: Union[str, None] = None
scopes: List[str] = []
class User(BaseModel):
username: str
email: Union[str, None] = None
full_name: Union[str, None] = None
disabled: Union[bool, None] = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: Union[timedelta, None] = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: str = Depends(oauth2_scheme)
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: User = Security(get_current_user, scopes=["me"]),
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: OAuth2PasswordRequestForm = Depends(),
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(current_user: User = Depends(get_current_active_user)):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: User = Security(get_current_active_user, scopes=["items"]),
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: User = Depends(get_current_user)):
return {"status": "ok"}
🤓 Other versions and variants
from datetime import datetime, timedelta, timezone
from typing import Annotated
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: str | None = None
scopes: list[str] = []
class User(BaseModel):
username: str
email: str | None = None
full_name: str | None = None
disabled: bool | None = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: timedelta | None = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: Annotated[str, Depends(oauth2_scheme)]
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: Annotated[User, Security(get_current_user, scopes=["me"])],
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: Annotated[OAuth2PasswordRequestForm, Depends()],
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(
current_user: Annotated[User, Depends(get_current_active_user)],
):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: Annotated[User, Security(get_current_active_user, scopes=["items"])],
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: Annotated[User, Depends(get_current_user)]):
return {"status": "ok"}
from datetime import datetime, timedelta, timezone
from typing import Annotated, List, Union
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: Union[str, None] = None
scopes: List[str] = []
class User(BaseModel):
username: str
email: Union[str, None] = None
full_name: Union[str, None] = None
disabled: Union[bool, None] = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: Union[timedelta, None] = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: Annotated[str, Depends(oauth2_scheme)]
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: Annotated[User, Security(get_current_user, scopes=["me"])],
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: Annotated[OAuth2PasswordRequestForm, Depends()],
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(
current_user: Annotated[User, Depends(get_current_active_user)],
):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: Annotated[User, Security(get_current_active_user, scopes=["items"])],
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: Annotated[User, Depends(get_current_user)]):
return {"status": "ok"}
from datetime import datetime, timedelta, timezone
from typing import List, Union
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
from typing_extensions import Annotated
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: Union[str, None] = None
scopes: List[str] = []
class User(BaseModel):
username: str
email: Union[str, None] = None
full_name: Union[str, None] = None
disabled: Union[bool, None] = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: Union[timedelta, None] = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: Annotated[str, Depends(oauth2_scheme)]
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: Annotated[User, Security(get_current_user, scopes=["me"])],
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: Annotated[OAuth2PasswordRequestForm, Depends()],
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(
current_user: Annotated[User, Depends(get_current_active_user)],
):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: Annotated[User, Security(get_current_active_user, scopes=["items"])],
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: Annotated[User, Depends(get_current_user)]):
return {"status": "ok"}
Tip
Prefer to use the Annotated
version if possible.
from datetime import datetime, timedelta, timezone
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: str | None = None
scopes: list[str] = []
class User(BaseModel):
username: str
email: str | None = None
full_name: str | None = None
disabled: bool | None = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: timedelta | None = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: str = Depends(oauth2_scheme)
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: User = Security(get_current_user, scopes=["me"]),
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: OAuth2PasswordRequestForm = Depends(),
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(current_user: User = Depends(get_current_active_user)):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: User = Security(get_current_active_user, scopes=["items"]),
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: User = Depends(get_current_user)):
return {"status": "ok"}
Tip
Prefer to use the Annotated
version if possible.
from datetime import datetime, timedelta, timezone
from typing import Union
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: Union[str, None] = None
scopes: list[str] = []
class User(BaseModel):
username: str
email: Union[str, None] = None
full_name: Union[str, None] = None
disabled: Union[bool, None] = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: Union[timedelta, None] = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: str = Depends(oauth2_scheme)
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: User = Security(get_current_user, scopes=["me"]),
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: OAuth2PasswordRequestForm = Depends(),
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(current_user: User = Depends(get_current_active_user)):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: User = Security(get_current_active_user, scopes=["items"]),
):
return [{"item_id": "Foo", "owner": current_user.username}]
@app.get("/status/")
async def read_system_status(current_user: User = Depends(get_current_user)):
return {"status": "ok"}
使用 scopes
¶
参数 security_scopes
的类型是 SecurityScopes
。
它的属性 scopes
是作用域列表,所有依赖项都把它作为子依赖项。也就是说所有依赖……这听起来有些绕,后文会有解释。
(类 SecurityScopes
的)security_scopes
对象还提供了单字符串类型的属性 scope_str
,该属性是(要在本例中使用的)用空格分割的作用域。
此处还创建了后续代码中要复用(raise
)的 HTTPException
。
该异常包含了作用域所需的(如有),以空格分割的字符串(使用 scope_str
)。该字符串要放到包含作用域的 WWW-Authenticate
请求头中(这也是规范的要求)。
from datetime import datetime, timedelta, timezone
from typing import List, Union
import jwt
from fastapi import Depends, FastAPI, HTTPException, Security, status
from fastapi.security import (
OAuth2PasswordBearer,
OAuth2PasswordRequestForm,
SecurityScopes,
)
from jwt.exceptions import InvalidTokenError
from passlib.context import CryptContext
from pydantic import BaseModel, ValidationError
# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
fake_users_db = {
"johndoe": {
"username": "johndoe",
"full_name": "John Doe",
"email": "johndoe@example.com",
"hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
"disabled": False,
},
"alice": {
"username": "alice",
"full_name": "Alice Chains",
"email": "alicechains@example.com",
"hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",
"disabled": True,
},
}
class Token(BaseModel):
access_token: str
token_type: str
class TokenData(BaseModel):
username: Union[str, None] = None
scopes: List[str] = []
class User(BaseModel):
username: str
email: Union[str, None] = None
full_name: Union[str, None] = None
disabled: Union[bool, None] = None
class UserInDB(User):
hashed_password: str
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(
tokenUrl="token",
scopes={"me": "Read information about the current user.", "items": "Read items."},
)
app = FastAPI()
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 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: Union[timedelta, None] = None):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(timezone.utc) + expires_delta
else:
expire = datetime.now(timezone.utc) + timedelta(minutes=15)
to_encode.update({"exp": expire})
encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
return encoded_jwt
async def get_current_user(
security_scopes: SecurityScopes, token: str = Depends(oauth2_scheme)
):
if security_scopes.scopes:
authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
else:
authenticate_value = "Bearer"
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": authenticate_value},
)
try:
payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
token_scopes = payload.get("scopes", [])
token_data = TokenData(scopes=token_scopes, username=username)
except (InvalidTokenError, ValidationError):
raise credentials_exception
user = get_user(fake_users_db, username=token_data.username)
if user is None:
raise credentials_exception
for scope in security_scopes.scopes:
if scope not in token_data.scopes:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Not enough permissions",
headers={"WWW-Authenticate": authenticate_value},
)
return user
async def get_current_active_user(
current_user: User = Security(get_current_user, scopes=["me"]),
):
if current_user.disabled:
raise HTTPException(status_code=400, detail="Inactive user")
return current_user
@app.post("/token")
async def login_for_access_token(
form_data: OAuth2PasswordRequestForm = Depends(),
) -> Token:
user = authenticate_user(fake_users_db, form_data.username, form_data.password)
if not user:
raise HTTPException(status_code=400, detail="Incorrect username or password")
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user.username, "scopes": form_data.scopes},
expires_delta=access_token_expires,
)
return Token(access_token=access_token, token_type="bearer")
@app.get("/users/me/", response_model=User)
async def read_users_me(current_user: User = Depends(get_current_active_user)):
return current_user
@app.get("/users/me/items/")
async def read_own_items(
current_user: User = Security(get_current_active_user, scopes=[