moved

email-worker/smtp/pool.py

@@ -0,0 +1,113 @@
+#!/usr/bin/env python3
+"""
+SMTP Connection Pool with robust connection handling
+"""
+
+import smtplib
+from queue import Queue, Empty
+from typing import Optional
+
+from logger import log
+from config import config
+
+
+class SMTPPool:
+    """Thread-safe SMTP Connection Pool"""
+    
+    def __init__(self, host: str, port: int, pool_size: int = 5):
+        self.host = host
+        self.port = port
+        self.pool_size = pool_size
+        self._pool: Queue = Queue(maxsize=pool_size)
+        self._initialized = False
+    
+    def _create_connection(self) -> Optional[smtplib.SMTP]:
+        """Create new SMTP connection"""
+        try:
+            conn = smtplib.SMTP(self.host, self.port, timeout=30)
+            conn.ehlo()
+            if config.smtp_use_tls:
+                conn.starttls()
+                conn.ehlo()
+            if config.smtp_user and config.smtp_pass:
+                conn.login(config.smtp_user, config.smtp_pass)
+            log(f"  📡 New SMTP connection created to {self.host}:{self.port}")
+            return conn
+        except Exception as e:
+            log(f"Failed to create SMTP connection: {e}", 'ERROR')
+            return None
+    
+    def _test_connection(self, conn: smtplib.SMTP) -> bool:
+        """Test if connection is still alive"""
+        try:
+            status = conn.noop()[0]
+            return status == 250
+        except Exception:
+            return False
+    
+    def initialize(self):
+        """Pre-create connections"""
+        if self._initialized:
+            return
+        
+        # Only 1-2 connections initially, rest on-demand
+        for _ in range(min(2, self.pool_size)):
+            conn = self._create_connection()
+            if conn:
+                self._pool.put(conn)
+        
+        self._initialized = True
+        log(f"SMTP pool initialized with {self._pool.qsize()} connections (max: {self.pool_size})")
+    
+    def get_connection(self, timeout: float = 5.0) -> Optional[smtplib.SMTP]:
+        """Get a valid connection from pool or create new one"""
+        # Try to get from pool
+        try:
+            conn = self._pool.get(block=False)
+            # Test if connection is still alive
+            if self._test_connection(conn):
+                return conn
+            else:
+                # Connection is dead, close and create new one
+                try:
+                    conn.quit()
+                except:
+                    pass
+                log(f"  ♻ Recycled stale SMTP connection")
+                return self._create_connection()
+        except Empty:
+            # Pool empty, create new connection
+            return self._create_connection()
+    
+    def return_connection(self, conn: smtplib.SMTP):
+        """Return connection to pool if still valid"""
+        if conn is None:
+            return
+        
+        # Check if connection is still good
+        if not self._test_connection(conn):
+            try:
+                conn.quit()
+            except:
+                pass
+            log(f"  🗑 Discarded broken SMTP connection")
+            return
+        
+        # Try to return to pool
+        try:
+            self._pool.put_nowait(conn)
+        except:
+            # Pool full, close connection
+            try:
+                conn.quit()
+            except:
+                pass
+    
+    def close_all(self):
+        """Close all connections"""
+        while not self._pool.empty():
+            try:
+                conn = self._pool.get_nowait()
+                conn.quit()
+            except:
+                pass