Starlette (and other ASGI frameworks)¶

There is no Starlette-specific integration in diwire (by design), but the pattern is the same as FastAPI:

Build a container at startup and make it globally accessible (often via diwire.container_context).
Create a request scope per incoming request.
Put request-bound objects (Request, user, trace id, etc.) into a ContextVar and register them via factories.

Minimal sketch¶

from contextvars import ContextVar
from typing import Annotated

from starlette.applications import Starlette
from starlette.requests import Request
from starlette.responses import JSONResponse

from diwire import Container, Injected, container_context

request_var: ContextVar[Request] = ContextVar("request_var")
app = Starlette()


async def middleware(request: Request, call_next):
    token = request_var.set(request)
    try:
        return await call_next(request)
    finally:
        request_var.reset(token)


app.middleware("http")(middleware)

container = Container()
container_context.set_current(container)

container.register(Request, factory=request_var.get, scope="request")


@container_context.resolve(scope="request")
async def handler(
    request: Request,
    service: Annotated["Service", Injected()],
) -> JSONResponse:
    return JSONResponse({"ok": True})

The exact routing API differs between frameworks, but the DI pieces stay the same.