feat: add foreign key constraints and metrics for blockchain node

apps/blockchain-node/src/aitbc_chain/rpc/websocket.py

@@ -0,0 +1,34 @@
+from __future__ import annotations
+
+import asyncio
+from typing import AsyncIterator, Dict
+
+from fastapi import APIRouter, WebSocket, WebSocketDisconnect
+
+from ..gossip import gossip_broker
+
+router = APIRouter(prefix="/ws", tags=["ws"])
+
+
+async def _stream_topic(topic: str, websocket: WebSocket) -> None:
+    subscription = await gossip_broker.subscribe(topic)
+    try:
+        while True:
+            message = await subscription.get()
+            await websocket.send_json(message)
+    except WebSocketDisconnect:
+        pass
+    finally:
+        subscription.close()
+
+
+@router.websocket("/blocks")
+async def blocks_stream(websocket: WebSocket) -> None:
+    await websocket.accept()
+    await _stream_topic("blocks", websocket)
+
+
+@router.websocket("/transactions")
+async def transactions_stream(websocket: WebSocket) -> None:
+    await websocket.accept()
+    await _stream_topic("transactions", websocket)