Websockets instead of polling

src/pirats/main.py

@@ -1,15 +1,17 @@
 from contextlib import asynccontextmanager
 from typing import Optional
-from fastapi import FastAPI, Form, Depends, HTTPException, APIRouter
+from fastapi import FastAPI, Form, Depends, HTTPException, APIRouter, WebSocket, WebSocketDisconnect
 from fastapi.responses import FileResponse
 from fastapi.staticfiles import StaticFiles
 from sqlmodel import Session
+import re
 import uvicorn
 import os
 from pathlib import Path
 
 from . import crud
 from .database import create_db_and_tables, get_session
+from .ws import manager
 
 EVENT_PAGE_SIZE = 50
 
@@ -23,6 +25,31 @@ async def lifespan(app: FastAPI):
 app = FastAPI(title="Rats with Gats Remote Play API", lifespan=lifespan)
 api = APIRouter()
 
+# Every state mutation is a POST under /api/game/{game_id}/..., so one
+# middleware can notify a game's websocket clients after any successful write.
+GAME_PATH_RE = re.compile(r"^/api/game/([^/]+)/")
+
+@app.middleware("http")
+async def broadcast_state_changes(request, call_next):
+    response = await call_next(request)
+    if request.method == "POST" and response.status_code < 400:
+        match = GAME_PATH_RE.match(request.url.path)
+        if match:
+            await manager.broadcast(match.group(1), {"type": "state_changed"})
+    return response
+
+@app.websocket("/api/game/{game_id}/ws")
+async def game_websocket(websocket: WebSocket, game_id: str):
+    await manager.connect(game_id, websocket)
+    try:
+        while True:
+            # Clients don't send anything meaningful; this just detects disconnects.
+            await websocket.receive_text()
+    except WebSocketDisconnect:
+        pass
+    finally:
+        manager.disconnect(game_id, websocket)
+
 # --- API Core Route Handlers ---
 
 @api.post("/game")