base.py 文件源码

def create_session(self):
        """
        Create a session context that communicates with the database.

        Commits all changes to the database before closing the session, and if an exception is raised,
        rollback the session.
        """
        session = Session(self.connection)
        logger.info("Create session {0} with {1}".format(
            id(session), self._public_db_uri(str(self.engine.url))))
        try:
            yield session
            session.commit()
            logger.info("Commit transactions to database")
        except Exception:
            session.rollback()
            logger.exception("Database transactions rolled back")
        finally:
            logger.info("Session {0} with {1} closed".format(
                id(session), self._public_db_uri(str(self.engine.url))))
            session.close()