import os
from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker, DeclarativeBase

DATABASE_URL = os.environ["DATABASE_URL"]

engine = create_engine(DATABASE_URL, pool_pre_ping=True)
SessionLocal = sessionmaker(bind=engine, autoflush=False, autocommit=False)

class Base(DeclarativeBase):
    pass

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