deploy: 2026-03-20 07:49

core/event_bus.py

@@ -0,0 +1,39 @@
+"""Simple async event bus for inter-module communication."""
+
+from __future__ import annotations
+
+import asyncio
+from collections import defaultdict
+from typing import Any, Callable, Coroutine, Dict, List
+
+from loguru import logger
+
+
+class EventBus:
+    """Publish-subscribe event bus using asyncio."""
+
+    def __init__(self):
+        self._subscribers: Dict[str, List[Callable]] = defaultdict(list)
+
+    def subscribe(self, event_type: str, handler: Callable[..., Coroutine]) -> None:
+        """Register an async handler for an event type."""
+        self._subscribers[event_type].append(handler)
+        logger.debug("Subscribed to '{}': {}", event_type, handler.__name__)
+
+    def unsubscribe(self, event_type: str, handler: Callable) -> None:
+        """Remove a handler from an event type."""
+        self._subscribers[event_type] = [
+            h for h in self._subscribers[event_type] if h != handler
+        ]
+
+    async def publish(self, event_type: str, data: Any = None) -> None:
+        """Publish an event, calling all registered handlers concurrently."""
+        handlers = self._subscribers.get(event_type, [])
+        if not handlers:
+            return
+        logger.debug("Publishing '{}' to {} handler(s)", event_type, len(handlers))
+        await asyncio.gather(*(h(data) for h in handlers), return_exceptions=True)
+
+
+# Module-level singleton
+event_bus = EventBus()