Initial commit

app/websocket.py

@@ -0,0 +1,92 @@
+"""WebSocket manager for real-time updates."""
+
+import asyncio
+import json
+import logging
+from typing import Any
+
+from fastapi import WebSocket
+
+logger = logging.getLogger(__name__)
+
+
+class WebSocketManager:
+    """Manages WebSocket connections and broadcasts events."""
+
+    def __init__(self):
+        self.active_connections: list[WebSocket] = []
+        self._lock = asyncio.Lock()
+
+    async def connect(self, websocket: WebSocket) -> None:
+        await websocket.accept()
+        async with self._lock:
+            self.active_connections.append(websocket)
+        logger.info("WebSocket client connected (%d total)", len(self.active_connections))
+
+    async def disconnect(self, websocket: WebSocket) -> None:
+        async with self._lock:
+            if websocket in self.active_connections:
+                self.active_connections.remove(websocket)
+        logger.info("WebSocket client disconnected (%d remaining)", len(self.active_connections))
+
+    async def broadcast(self, event_type: str, data: Any) -> None:
+        """Broadcast an event to all connected clients."""
+        if not self.active_connections:
+            return
+
+        message = json.dumps({"type": event_type, "data": data})
+
+        async with self._lock:
+            disconnected = []
+            for connection in self.active_connections:
+                try:
+                    await connection.send_text(message)
+                except Exception as e:
+                    logger.debug("Failed to send to client: %s", e)
+                    disconnected.append(connection)
+
+            # Clean up disconnected clients
+            for conn in disconnected:
+                if conn in self.active_connections:
+                    self.active_connections.remove(conn)
+
+    async def send_personal(self, websocket: WebSocket, event_type: str, data: Any) -> None:
+        """Send an event to a specific client."""
+        message = json.dumps({"type": event_type, "data": data})
+        try:
+            await websocket.send_text(message)
+        except Exception as e:
+            logger.debug("Failed to send to client: %s", e)
+
+
+# Global instance
+ws_manager = WebSocketManager()
+
+
+def broadcast_event(event_type: str, data: dict) -> None:
+    """Schedule a broadcast without blocking.
+
+    Convenience function that creates an asyncio task to broadcast
+    an event to all connected WebSocket clients.
+    """
+    asyncio.create_task(ws_manager.broadcast(event_type, data))
+
+
+def broadcast_error(message: str, details: str | None = None) -> None:
+    """Broadcast an error notification to all connected clients.
+
+    This appears as a toast notification in the frontend.
+    """
+    data = {"message": message}
+    if details:
+        data["details"] = details
+    asyncio.create_task(ws_manager.broadcast("error", data))
+
+
+def broadcast_health(radio_connected: bool, serial_port: str | None = None) -> None:
+    """Broadcast health status change to all connected clients."""
+    asyncio.create_task(ws_manager.broadcast("health", {
+        "status": "ok" if radio_connected else "degraded",
+        "radio_connected": radio_connected,
+        "serial_port": serial_port,
+    }))