Refactoring code for modular approach

app/core/lifespan.py

@@ -0,0 +1,48 @@
+from contextlib import asynccontextmanager
+from fastapi import FastAPI
+from sqlalchemy import text
+from .logging import setup_logging
+from .database import engine
+from models.database_models import Base
+import logging
+
+logger = logging.getLogger(__name__)
+
+@asynccontextmanager
+async def lifespan(app: FastAPI):
+    """Application lifespan events"""
+    # Startup
+    logger = setup_logging()  # Configure logging first
+    logger.info("Starting up ecommerce API")
+
+    # Create tables
+    Base.metadata.create_all(bind=engine)
+
+    # Create indexes
+    create_indexes()
+
+    yield
+
+    # Shutdown
+    logger.info("Shutting down ecommerce API")
+
+
+def create_indexes():
+    """Create database indexes"""
+    with engine.connect() as conn:
+        try:
+            # User indexes
+            conn.execute(text("CREATE INDEX IF NOT EXISTS idx_user_email ON users(email)"))
+            conn.execute(text("CREATE INDEX IF NOT EXISTS idx_user_username ON users(username)"))
+
+            # Product indexes
+            conn.execute(text("CREATE INDEX IF NOT EXISTS idx_product_gtin ON products(gtin)"))
+            conn.execute(text("CREATE INDEX IF NOT EXISTS idx_product_marketplace ON products(marketplace)"))
+
+            # Stock indexes
+            conn.execute(text("CREATE INDEX IF NOT EXISTS idx_stock_gtin_location ON stock(gtin, location)"))
+
+            conn.commit()
+            logger.info("Database indexes created successfully")
+        except Exception as e:
+            logger.warning(f"Index creation warning: {e}")