init

backend/ws.py

@@ -0,0 +1,46 @@
+"""WS-Hub (R1): EINE Queue + EIN Sender-Task — Broadcasts bleiben geordnet.
+Payload ist nur ein dirty-Signal {typ, topic, bereich}; der Client lädt selbst."""
+import asyncio
+import json
+
+
+class Hub:
+    def __init__(self) -> None:
+        self._clients: set = set()
+        self._queue: asyncio.Queue | None = None
+        self._loop: asyncio.AbstractEventLoop | None = None
+
+    def bind_loop(self, loop: asyncio.AbstractEventLoop) -> None:
+        self._loop = loop
+        self._queue = asyncio.Queue()
+        loop.create_task(self._sende_schleife())
+
+    def push(self, tabelle: str, row: dict) -> None:
+        """Thread-sicher aus der DB-Schicht aufrufbar."""
+        if self._loop is None or self._queue is None:
+            return
+        bereich = {"tasks": "graph", "gate_laeufe": "graph", "befunde": "graph",
+                   "runs": "run", "topics": "run"}.get(tabelle, "graph")
+        msg = json.dumps({"typ": "dirty", "bereich": bereich}, ensure_ascii=False)
+        self._loop.call_soon_threadsafe(self._queue.put_nowait, msg)
+
+    async def _sende_schleife(self) -> None:
+        while True:
+            msg = await self._queue.get()
+            tot = []
+            for ws in list(self._clients):
+                try:
+                    await ws.send_text(msg)
+                except Exception:
+                    tot.append(ws)
+            for ws in tot:
+                self._clients.discard(ws)
+
+    def connect(self, ws) -> None:
+        self._clients.add(ws)
+
+    def disconnect(self, ws) -> None:
+        self._clients.discard(ws)
+
+
+hub = Hub()