Frist commit

backend/db/pool.py

@@ -0,0 +1,56 @@
+"""PostgreSQL connection pool."""
+
+from __future__ import annotations
+
+import logging
+
+from psycopg_pool import AsyncConnectionPool
+
+from config import DATABASE_URL
+
+logger = logging.getLogger("mail_summary")
+
+_pool: AsyncConnectionPool | None = None
+_pool_enabled = False
+
+
+async def init_pool() -> None:
+    global _pool, _pool_enabled
+    if _pool is not None:
+        return
+
+    try:
+        pool = AsyncConnectionPool(
+            conninfo=DATABASE_URL,
+            min_size=1,
+            max_size=10,
+            open=False,
+        )
+        await pool.open()
+        _pool = pool
+        _pool_enabled = True
+        logger.info("PostgreSQL connection pool initialized")
+    except Exception:
+        _pool = None
+        _pool_enabled = False
+        logger.exception("PostgreSQL unavailable")
+
+
+async def close_pool() -> None:
+    global _pool, _pool_enabled
+    if _pool is None:
+        return
+    await _pool.close()
+    _pool = None
+    _pool_enabled = False
+    logger.info("PostgreSQL connection pool closed")
+
+
+def pool_enabled() -> bool:
+    return _pool_enabled and _pool is not None
+
+
+def get_pool() -> AsyncConnectionPool:
+    if _pool is None:
+        raise RuntimeError("Database pool is not initialized")
+    return _pool