The two lanes

Not every endpoint is a resource. asgimachine has two first-class lanes that share the same Starlette substrate:

• The resource lane — walks the decision graph. For anything with a URL that names a thing you GET/PUT/DELETE, where conditional requests, negotiation, and method handling are genuinely useful.
• The command lane — a plain request→response handler that skips the graph. For genuinely command-shaped endpoints: a credential exchange, a webhook receiver, an RPC-ish action.

No cosplay

The tell that an endpoint belongs in the command lane: you find yourself inventing an unaddressable noun and faking resource_exists / represent to satisfy the graph model. Don't. Let commands be commands.

A command

A Command implements one method:

from asgimachine.command import Command, json_response
from asgimachine.substrate.starlette import build_app, command_route


class Token(Command):
    def __init__(self, store):
        self._store = store

    async def handle(self, request):
        body = json.loads(await request.body())
        if not self._store.verify(body["username"], body["password"]):
            return json_response({"error": "invalid credentials"}, status=401)
        return json_response({"token": self._store.issue(body["username"])}, status=201)


app = build_app([command_route("/token", Token(store))])

Because a command doesn't walk the graph, the router owns method restriction (a 405 for an unlisted method) — which is fine for a command-shaped endpoint. The request-body cap still applies: command_route(..., max_body_bytes=…) bounds the read, and an over-cap body is a 413.

Mixing them

A single app freely composes both:

app = build_app([
    resource_route("/notes", NotesCollection(store)),
    resource_route("/notes/{id}", NoteMember(store, policy)),
    command_route("/token", Token(store)),
])

See the notes_app example for the full gradient — public resource, simple-auth collection, policy-governed member, plus the command lane — coexisting without cosplay.