app/db/session.py

from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker

from app.config import settings

engine = create_engine(
    settings.database_url,
    pool_pre_ping=True,
    pool_recycle=300,
)
SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)


def get_db():
    db = SessionLocal()
    try:
        yield db
    finally:
        db.close()