Implement prune_all_connections

edb/server/connpool/pool2.py

@@ -107,15 +107,7 @@ def __init__(self, *, connect: Connector[C],
         self._successful_disconnects = 0
 
         if stats_collector:
-            stats_collector(Snapshot(
-                timestamp=0,
-                capacity=10,
-                blocks=[],
-                log=[],
-                failed_connects=0,
-                failed_disconnects=0,
-                successful_connects=0,
-                successful_disconnects=0))
+            stats_collector(self._build_snapshot(now=0))
         pass
 
     def __del__(self) -> None:
@@ -214,7 +206,11 @@ async def prune_inactive_connections(self, dbname: str) -> None:
         del self._prunes[id]
 
     async def prune_all_connections(self) -> None:
-        pass
+        # Brutally close all connections. This is used by HA failover.
+        coros = []
+        for conn in self._conns.values():
+            coros.append(self._disconnect(conn))
+        await asyncio.gather(*coros, return_exceptions=True)
 
     def get_pending_conns(self) -> int:
         return 0