| import os | |
| from dotenv import load_dotenv | |
| from sqlalchemy import create_engine | |
| from sqlalchemy.orm import DeclarativeBase, sessionmaker | |
| load_dotenv() | |
| DATABASE_URL = os.getenv("DATABASE_URL", "sqlite:///./atom.db") | |
| # Optimization: Connection Pooling | |
| # For SQLite, we use StaticPool for in-memory or simple file-based access | |
| # For PostgreSQL (production), we would use QueuePool with specific settings | |
| connect_args = {"check_same_thread": False} if "sqlite" in DATABASE_URL else {} | |
| engine = create_engine( | |
| DATABASE_URL, | |
| connect_args=connect_args, | |
| pool_pre_ping=True, # Verify connection before usage | |
| pool_recycle=3600, # Recycle connections every hour | |
| echo=False # Disable SQL logging for performance | |
| ) | |
| SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine) | |
| class Base(DeclarativeBase): | |
| pass | |
| def get_db(): | |
| with get_db_session() as db: | |
| try: | |
| yield db | |
| finally: | |
| db.close() | |