Chat room

Multi-room chat with SQLite. The larger-app step after Realtime tiles. Source: examples/chat-room.

You should already know the tiles loop (Relay, c.alive, CQRS-shaped routes). Hello world is optional — it is only bootstrap and one HTML page. This page is the behaviour of the chat-room tree. File roles live in Structuring apps.

1. Run it

bash

git clone https://github.com/bobowski/stario.git

cd stario/examples/chat-room

uv sync

uv run stario watch app.main:bootstrap

Open http://127.0.0.1:8000 (set STARIO_PORT if the default is busy). Tests: uv run pytest.

2. What this example adds

Concern	Tiles	Chat room
Layout	One file	Features under `app/features/`
State	In-memory `Game`	SQLite via `app/db.py`
Config	Constants in file	`Config.from_env()`
Tests	None in example	`tests/test_lobby.py`, `tests/test_room.py`

The HTTP pattern is the same as tiles: GET paints HTML once, GET /subscribe stays open with SSE(w).patch_elements, and POST commands reply 204, then work, then publish through Relay. Lobby create / delete redirect.

3. Start at `bootstrap`

app/main.py reads config, opens Database and Relay, registers static assets, then calls each register_*.

python

async def bootstrap(app: App, span: Span):

    config = Config.from_env()

    db = Database(config.db_path)

    db.apply_schema(room_data.SCHEMA)

    relay = Relay()

    await ASSETS.attach(app)

    register_lobby(app, db, relay)

    register_room(app, db, relay)

    yield

Nothing in app/features/ imports bootstrap.

4. Routes and jobs

Route	Job
`GET /`	Lobby — list rooms and online counts
`GET /subscribe`	Lobby SSE — patch the room list on relay events
`POST /rooms`	Create room from dialog signals
`DELETE /rooms/{id}`	Delete room and related rows
`GET /rooms/{id}`	First paint; mint demo user identity
`GET /rooms/{id}/subscribe`	Long-lived SSE; patch HTML on relay events
`POST /rooms/{id}/send`	204 first, then store and publish
`POST /rooms/{id}/typing`	204 first, then typing flag and publish

Commands read signals via read_*_signals and validate in plain Python. Subscribe handlers open async with relay.subscribe(...) as live: and loop with async for subject, _ in c.alive(live):. When a room is deleted under open tabs, the handler calls SSE(w).navigate(LOBBY.href()).

Room endpoints are Route constants in app/features/room/urls.py. Handlers register app.add(ROOM, …). Views call SEND.href(room_id=room.id) or at.post(SEND.href(room.id)).

5. Configuration and tests

CHAT_DB_PATH defaults to :memory:. Stario does not load dotenv files. Server listen address and tracers use STARIO_* (Configuration).

Tests use async with TestClient(app.main.bootstrap) — the same bootstrap the CLI loads. Testing with TestClient.

Structuring apps. Injecting dependencies.