如何使用FastAPI/Starlette获取路由名称？

Question

如何使用FastAPI/Starlette获得路由/端点的name？我可以访问Request对象，我需要在我的一个中间件中提供这些信息。例如，如果我点击services/1，那么我应该能够获得abc名称。这在FastAPI中是可能的吗？

@app.get("/services/{service}", name="abc")
async def list_services() -> dict:
    do something

更新1: request.scope的输出

{'type': 'http', 'asgi': {'version': '3.0', 'spec_version': '2.3'}, 'http_version': '1.1', 'server': ('127.0.0.1', 8001), 'client': ('127.0.0.1', 56670), 'scheme': 'http', 'root_path': '', 'headers': [(b'user-agent', b'PostmanRuntime/7.29.2'), (b'accept', b'*/*'), (b'postman-token', b'f2da2d0f-e721-44c8-b14f-e19750ea8a68'), (b'host', b'localhost:8001'), (b'accept-encoding', b'gzip, deflate, br'), (b'connection', b'keep-alive')], 'method': 'GET', 'path': '/health', 'raw_path': b'/health', 'query_string': b'', 'app': <fastapi.applications.FastAPI object at 0x1036d5790>}

更新2:在request.scope“路由”中断的地方提供中间件代码。

from fastapi import FastAPI,Request
    
app = FastAPI()


@app.middleware("http")
async def logging_middleware(request: Request, call_next):
    print(request.scope['route'].name)
    response = await call_next(request)
    return response

@app.get('/', name='abc')
def get_name(request: Request):
    return request.scope['route'].name

Answer 1

您可以获得如下的name值：

from fastapi import FastAPI,Request
    
app = FastAPI()

@app.get('/', name='abc')
def get_name(request: Request):
    return request.scope['route'].name

在中间件中，确保在调用name后获得路由的call_next(request)，否则将面临KeyError: 'route'，因为scope字典中还不存在route密钥/对象。示例：

@app.middleware("http")
async def some_middleware(request: Request, call_next):
    response = await call_next(request)
    print(request.scope['route'].name)
    return response

与中间件不同，您可以创建一个custom APIRoute class in a router，它允许您在处理request和获取response之前获得路由的name (如果这是应用程序的要求)。您可以添加希望由APIRoute类使用@<name_of_router_instance>而不是@app (例如，@router.get('/', name='abc'))处理的端点。可以以相同的方式添加多个端点。示例：

from fastapi import APIRouter, FastAPI, Request, Response
from typing import Callable
from fastapi.routing import APIRoute

class CheckNameRoute(APIRoute):
    def get_route_handler(self) -> Callable:
        original_route_handler = super().get_route_handler()

        async def custom_route_handler(request: Request) -> Response:
            print(request.scope['route'].name)
            response = await original_route_handler(request)
            return response

        return custom_route_handler


app = FastAPI()
router = APIRouter(route_class=CheckNameRoute)
    
@router.get('/', name='abc')
def get_name(request: Request):
    return request.scope['route'].name
 
app.include_router(router)