Starlette integration

RequestScope

Bases: RequestScope[Scope, Receive, Send]

ASGI middleware that opens a depin async scope around every Starlette request.

Implemented directly against the ASGI protocol (not Starlette's BaseHTTPMiddleware) so streaming responses, server-sent events, and WebSockets pass through without buffering.

The container is published to the connection's context for the duration of the scope, so depin.hosted_container() reaches it from anywhere inside the request.

A connection scope that is neither http nor websocket — the lifespan scope above all — is forwarded untouched: no scope is opened and nothing is published. A websocket is scoped and hosted exactly like an HTTP request, but it is not seeded, because it has no request-body semantics and starlette.requests.Request is HTTP-shaped.

For HTTP requests it places a metadata-only starlette.requests.Request into the active scope frame so scoped providers can read headers, URL, cookies, and state. That Request carries no receive channel: reading the body through it raises rather than consuming the stream the route handler needs (which would otherwise deadlock against the framework's own body parsing). Treat the body as a typed route parameter, not a provider input.

Parameters:

Name	Type	Description	Default
app	ASGIApp	The downstream ASGI application this middleware wraps.	required
container	FrozenContainer	The frozen container to host for the duration of each request. Keyword-or-positional because the framework helpers that install middleware pass app positionally and container by keyword.	required

Raises:

Type	Description
ExceptionGroup	One or more teardowns failed when the request's scope closed. Every failure is included; one does not hide another.

Example

Install the middleware once, then resolve scoped providers per request::

app = Starlette(routes=routes)
app.add_middleware(RequestScope, container=di)

seed_request

seed_request(scope: Scope) -> ScopeSeed

Build the starlette.requests.Request that RequestScope places into each HTTP frame.

The request is constructed from the connection scope alone, which is what makes it metadata-only: see RequestScope for what that costs and why.

Parameters:

Name	Type	Description	Default
scope	Scope	The ASGI connection scope of the request being opened.	required

Returns:

Type	Description
ScopeSeed	The key to bind the request under, and the request itself.

Example

scope = { ... 'type': 'http', ... 'method': 'POST', ... 'path': '/orders', ... 'headers': [(b'x-tenant', b'acme')], ... } seed = seed_request(scope) seed.key is Request True seed.value.headers['x-tenant'] 'acme'