add utility for database

backend/src/network_sniffer.py

@@ -9,6 +9,7 @@ import struct
 from typing import Dict, List, Optional, Any
 
 import asyncpg
+from backend.src.utilities.database import DB
 from scapy.all import (
     Ether,
     ARP,
@@ -59,72 +60,11 @@ threading.Thread(target=_start_async_loop, args=(async_loop,), daemon=True).star
 
 
 # -------------------------
-# Database helper (pool)
+# Database init (pool)
 # -------------------------
-class DB:
-    _pool: Optional[asyncpg.pool.Pool] = None
-
-    @classmethod
-    async def init_pool(cls) -> None:
-        if cls._pool is None:
-            cls._pool = await asyncpg.create_pool(dsn=DB_DSN, min_size=1, max_size=5)
-            logger.info("DB pool initialized")
-
-    @classmethod
-    async def close_pool(cls) -> None:
-        if cls._pool:
-            await cls._pool.close()
-            cls._pool = None
-            logger.info("DB pool closed")
-
-    @classmethod
-    async def insert_packet(cls, pkt_info: Dict[str, Any]) -> None:
-        """
-        Insert packet metadata into DB. This preserves the exact columns/values in the original code.
-        """
-        if cls._pool is None:
-            # defensive: try to initialize if not ready
-            await cls.init_pool()
-
-        try:
-            async with cls._pool.acquire() as conn:
-                await conn.execute(
-                    """
-                    INSERT INTO packets(
-                        iface,
-                        src_mac,
-                        dst_mac,
-                        eth_type,
-                        vlan_id,
-                        src_ip,
-                        dst_ip,
-                        ip_proto,
-                        src_port,
-                        dst_port,
-                        length,
-                        raw
-                    ) VALUES($1,$2,$3,$4,$5,$6,$7,$8,$9,$10,$11,$12)
-                    """,
-                    pkt_info["iface"],
-                    pkt_info.get("src_mac"),
-                    pkt_info.get("dst_mac"),
-                    pkt_info.get("eth_type"),
-                    pkt_info.get("vlan_id"),
-                    pkt_info.get("src_ip"),
-                    pkt_info.get("dst_ip"),
-                    pkt_info.get("protocol"),
-                    pkt_info.get("src_port"),
-                    pkt_info.get("dst_port"),
-                    pkt_info["length"],
-                    pkt_info["raw"],
-                )
-        except Exception:
-            # keep sniffer alive: log and continue
-            logger.exception("DB insert failed")
-
-
+db = DB(DB_DSN)
 # schedule pool init on background loop (fire-and-forget)
-asyncio.run_coroutine_threadsafe(DB.init_pool(), async_loop)
+asyncio.run_coroutine_threadsafe(db.init_pool(), async_loop)
 
 
 # -------------------------
@@ -278,7 +218,7 @@ def parse_packet(pkt, bridge: str) -> None:
 
     # Submit DB insert to background loop (non-blocking)
     try:
-        asyncio.run_coroutine_threadsafe(DB.insert_packet(pkt_info), async_loop)
+        asyncio.run_coroutine_threadsafe(db.insert_packet(pkt_info), async_loop)
     except Exception:
         logger.exception("Failed to schedule DB insert")
 
@@ -481,7 +421,7 @@ def stop_afpacket_sniffer() -> None:
 
     # close db pool (schedule on async loop)
     try:
-        asyncio.run_coroutine_threadsafe(DB.close_pool(), async_loop)
+        asyncio.run_coroutine_threadsafe(db.close_pool(), async_loop)
     except Exception:
         logger.exception("Failed to schedule DB pool close")
 

backend/src/utilities/database.py

@@ -0,0 +1,79 @@
+
+import logging
+from typing import Dict, List, Optional, Any
+
+import asyncpg
+
+# ---- Logging ----------------------------------------------------------
+logging.basicConfig(level=logging.INFO)
+logger = logging.getLogger("af_packet_sniffer")
+
+class DB:
+    def __init__(self, dsn: str, min_size: int = 1, max_size: int = 5):
+        """
+        Create a DB helper bound to the given DSN.
+        Pool is created lazily on first use unless init_pool() is explicitly called.
+        """
+        self._dsn = dsn
+        self._pool: Optional[asyncpg.pool.Pool] = None
+        self._min_size = min_size
+        self._max_size = max_size
+
+    async def init_pool(self) -> None:
+        """Create connection pool if not already created."""
+        if self._pool is None:
+            self._pool = await asyncpg.create_pool(
+                dsn=self._dsn,
+                min_size=self._min_size,
+                max_size=self._max_size,
+            )
+            logger.info("DB pool initialized")
+
+    async def close_pool(self) -> None:
+        """Gracefully close connection pool."""
+        if self._pool:
+            await self._pool.close()
+            self._pool = None
+            logger.info("DB pool closed")
+
+    async def insert_packet(self, pkt_info: Dict[str, Any]) -> None:
+        """
+        Insert packet metadata. Same fields + same SQL statement as before.
+        """
+        if self._pool is None:
+            await self.init_pool()  # lazy init
+
+        try:
+            async with self._pool.acquire() as conn:
+                await conn.execute(
+                    """
+                    INSERT INTO packets(
+                        iface,
+                        src_mac,
+                        dst_mac,
+                        eth_type,
+                        vlan_id,
+                        src_ip,
+                        dst_ip,
+                        ip_proto,
+                        src_port,
+                        dst_port,
+                        length,
+                        raw
+                    ) VALUES($1,$2,$3,$4,$5,$6,$7,$8,$9,$10,$11,$12)
+                    """,
+                    pkt_info["iface"],
+                    pkt_info.get("src_mac"),
+                    pkt_info.get("dst_mac"),
+                    pkt_info.get("eth_type"),
+                    pkt_info.get("vlan_id"),
+                    pkt_info.get("src_ip"),
+                    pkt_info.get("dst_ip"),
+                    pkt_info.get("protocol"),
+                    pkt_info.get("src_port"),
+                    pkt_info.get("dst_port"),
+                    pkt_info["length"],
+                    pkt_info["raw"],
+                )
+        except Exception:
+            logger.exception("DB insert failed")