python-dependency-injector/examples/miniapps/fastapi-sqlalchemy/webapp/database.py
2021-09-30 19:05:57 -04:00

42 lines
1.1 KiB
Python

"""Database module."""
from contextlib import contextmanager, AbstractContextManager
from typing import Callable
import logging
from sqlalchemy import create_engine, orm
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import Session
logger = logging.getLogger(__name__)
Base = declarative_base()
class Database:
def __init__(self, db_url: str) -> None:
self._engine = create_engine(db_url, echo=True)
self._session_factory = orm.scoped_session(
orm.sessionmaker(
autocommit=False,
autoflush=False,
bind=self._engine,
),
)
def create_database(self) -> None:
Base.metadata.create_all(self._engine)
@contextmanager
def session(self) -> Callable[..., AbstractContextManager[Session]]:
session: Session = self._session_factory()
try:
yield session
except Exception:
logger.exception("Session rollback because of exception")
session.rollback()
raise
finally:
session.close()