python-3.x - 如何在 FastAPI 中使用带路由的中间件

Question

我正在关注 FastAPI 文档 here并尝试使用中间件实现路由。 我的主要包含:

app = FastAPI()


app.include_router(
    SomeService.router,
    prefix="/services",
    tags=["services"]
)


@app.middleware("http")
async def add_process_time_header(request: Request, call_next):
    start_time = time.time()
    response = await call_next(request)
    process_time = time.time() - start_time
    response.headers["X-Process-Time"] = str(process_time)
    return response

发送请求时，正确执行并返回正确的值，但不包含通过中间件追加的值。

我尝试在服务路由中定义中间件 并在 app.include_router 之前定义中间件

Answer 1

documentation about middleware提到如果

(...) you want a client in a browser to be able to see [the custom headers], you need to add them to your CORS configurations, using the parameter expose_headers documented in Starlette's CORS docs.