Starlette代码仅支持GET请求，需改为POST请求的技术咨询

你只需要对现有代码做两处关键修改，就能适配POST请求场景，完全不需要重写：

1. 给路由指定允许的HTTP方法 #

Starlette的Route默认仅接受GET请求，必须显式声明支持POST方法：

routes = [
    Route("/testpath", endpoint=homepage, methods=["POST"])
]

2. 修复响应构造的错误 #

原代码中JSONResponse的参数顺序错误，你把请求体body放在了第二个参数位置（该位置应为状态码等可选参数），需要调整响应数据的构造方式：

async def homepage(request):
    if request.user.is_authenticated:
        body = await request.json()
        # 将请求体整合到响应数据中，或根据业务需求处理
        return JSONResponse({
            "user": my_user, 
            "password": my_pass, 
            "header": request.headers.get('client_id'),
            "request_body": body
        })
    return PlainTextResponse('Hello, you')

额外优化建议：避免使用全局变量 #

原代码用my_user和my_pass全局变量存储用户信息是线程不安全的，并发请求下会出现数据混乱。建议将用户信息存入request.state：

# 在BasicAuthBackend的authenticate方法中修改
async def authenticate(self, conn):
    # ... 原有代码 ...
    username, _, password = decoded.partition(":")
    # 存入request.state而非全局变量
    conn.state.username = username
    conn.state.password = password
    return AuthCredentials(["authenticated"]), SimpleUser(username)

然后在视图函数中从request.state读取：

async def homepage(request):
    if request.user.is_authenticated:
        body = await request.json()
        return JSONResponse({
            "user": request.state.username, 
            "password": request.state.password, 
            "header": request.headers.get('client_id'),
            "request_body": body
        })
    return PlainTextResponse('Hello, you')

修改后的完整代码 #

from starlette.applications import Starlette
from starlette.authentication import (
    AuthCredentials, AuthenticationBackend, AuthenticationError, SimpleUser
)
from starlette.middleware import Middleware
from starlette.middleware.authentication import AuthenticationMiddleware
from starlette.responses import (PlainTextResponse, JSONResponse)
from starlette.routing import Route
import base64
import binascii

class BasicAuthBackend(AuthenticationBackend):
    async def authenticate(self, conn):
        if "Authorization" not in conn.headers:
            return

        auth = conn.headers["Authorization"]
        try:
            scheme, credentials = auth.split()
            if scheme.lower() != 'basic':
                return
            decoded = base64.b64decode(credentials).decode("ascii")
        except (ValueError, UnicodeDecodeError, binascii.Error) as exc:
            raise AuthenticationError('Invalid basic auth credentials')
        username, _, password = decoded.partition(":")
        conn.state.username = username
        conn.state.password = password
        # TODO: 此处需添加用户名密码的实际验证逻辑
        return AuthCredentials(["authenticated"]), SimpleUser(username)


async def homepage(request):
    if request.user.is_authenticated:
        body = await request.json()
        return JSONResponse({
            "user": request.state.username,
            "password": request.state.password,
            "header": request.headers.get('client_id'),
            "request_body": body
        })
    return PlainTextResponse('Hello, you')

routes = [
    Route("/testpath", endpoint=homepage, methods=["POST"])
]

middleware = [
    Middleware(AuthenticationMiddleware, backend=BasicAuthBackend())
]

app = Starlette(debug=True, routes=routes, middleware=middleware)

内容的提问来源于stack exchange，提问作者Nick Ellson