Method modified_send

tests/test_routing.py:949–952

(msg: Message)

        async def __call__(self, scope: Scope, receive: Receive, send: Send) -> None:
            async def modified_send(msg: Message) -> None:
                if msg["type"] == "http.response.start":
                    msg["headers"].append((f"X-{self.name}".encode(), b"true"))
                await send(msg)

            await self.app(scope, receive, modified_send)