initializer service deployed and tested

api_services/api_controllers/postgres/engine.py

@@ -0,0 +1,63 @@
+from contextlib import contextmanager
+from functools import lru_cache
+from typing import Generator
+from api_controllers.postgres.config import postgres_configs
+
+from sqlalchemy import create_engine
+from sqlalchemy.orm import declarative_base, sessionmaker, scoped_session, Session
+
+
+# Configure the database engine with proper pooling
+engine = create_engine(
+    postgres_configs.url,
+    pool_pre_ping=True,
+    pool_size=10,  # Reduced from 20 to better match your CPU cores
+    max_overflow=5,  # Reduced from 10 to prevent too many connections
+    pool_recycle=600,  # Keep as is
+    pool_timeout=30,  # Keep as is
+    echo=False,  # Consider setting to False in production
+)
+
+
+Base = declarative_base()
+
+
+# Create a cached session factory
+@lru_cache()
+def get_session_factory() -> scoped_session:
+    """Create a thread-safe session factory."""
+    session_local = sessionmaker(
+        bind=engine,
+        autocommit=False,
+        autoflush=False,
+        expire_on_commit=True,  # Prevent expired object issues
+    )
+    return scoped_session(session_local)
+
+
+# Get database session with proper connection management
+@contextmanager
+def get_db() -> Generator[Session, None, None]:
+    """Get database session with proper connection management.
+
+    This context manager ensures:
+    - Proper connection pooling
+    - Session cleanup
+    - Connection return to pool
+    - Thread safety
+
+    Yields:
+        Session: SQLAlchemy session object
+    """
+
+    session_factory = get_session_factory()
+    session = session_factory()
+    try:
+        yield session
+        session.commit()
+    except Exception:
+        session.rollback()
+        raise
+    finally:
+        session.close()
+        session_factory.remove()  # Clean up the session from the registry