update

Backend/src/config/database.py

@@ -1,38 +1,63 @@
-from sqlalchemy import create_engine
+from sqlalchemy import create_engine, event
 from sqlalchemy.ext.declarative import declarative_base
 from sqlalchemy.orm import sessionmaker
-import os
-from dotenv import load_dotenv
+from sqlalchemy.pool import QueuePool
+from .settings import settings
+from .logging_config import get_logger
 
-load_dotenv()
+logger = get_logger(__name__)
 
-# Database configuration
-DB_USER = os.getenv("DB_USER", "root")
-DB_PASS = os.getenv("DB_PASS", "")
-DB_NAME = os.getenv("DB_NAME", "hotel_db")
-DB_HOST = os.getenv("DB_HOST", "localhost")
-DB_PORT = os.getenv("DB_PORT", "3306")
-
-DATABASE_URL = f"mysql+pymysql://{DB_USER}:{DB_PASS}@{DB_HOST}:{DB_PORT}/{DB_NAME}"
+# Database configuration using settings
+DATABASE_URL = settings.database_url
 
+# Enhanced engine configuration for enterprise use
 engine = create_engine(
     DATABASE_URL,
-    pool_pre_ping=True,
-    pool_recycle=300,
-    pool_size=5,
-    max_overflow=10,
-    echo=os.getenv("NODE_ENV") == "development"
+    poolclass=QueuePool,
+    pool_pre_ping=True,  # Verify connections before using
+    pool_recycle=3600,  # Recycle connections after 1 hour
+    pool_size=10,  # Number of connections to maintain
+    max_overflow=20,  # Additional connections beyond pool_size
+    echo=settings.is_development,  # Log SQL queries in development
+    future=True,  # Use SQLAlchemy 2.0 style
+    connect_args={
+        "charset": "utf8mb4",
+        "connect_timeout": 10
+    }
 )
 
+# Event listeners for connection pool monitoring
+@event.listens_for(engine, "connect")
+def set_sqlite_pragma(dbapi_conn, connection_record):
+    """Set connection-level settings"""
+    logger.debug("New database connection established")
+
+@event.listens_for(engine, "checkout")
+def receive_checkout(dbapi_conn, connection_record, connection_proxy):
+    """Log connection checkout"""
+    logger.debug("Connection checked out from pool")
+
+@event.listens_for(engine, "checkin")
+def receive_checkin(dbapi_conn, connection_record):
+    """Log connection checkin"""
+    logger.debug("Connection returned to pool")
+
 SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
 
 Base = declarative_base()
 
 # Dependency to get DB session
 def get_db():
+    """
+    Dependency for getting database session.
+    Automatically handles session lifecycle.
+    """
     db = SessionLocal()
     try:
         yield db
+    except Exception:
+        db.rollback()
+        raise
     finally:
         db.close()