1.4 KiB
1.4 KiB
Usage
To use oslo.db in a project:
* Session Handling
from oslo.db.sqlalchemy import session as db_session = None _FACADE def _create_facade_lazily(): global _FACADE if _FACADE is None: = db_session.EngineFacade.from_config( _FACADE CONF.database.connection, CONF)return _FACADE def get_engine(): = _create_facade_lazily() facade return facade.get_engine() def get_session(**kwargs): = _create_facade_lazily() facade return facade.get_session(**kwargs)
Base class for models usage
from oslo.db import models class ProjectSomething(models.TimestampMixin, models.ModelBase):id = Column(Integer, primary_key=True) ...
DB API backend support
from oslo.config import cfg from oslo.db import api as db_api = cfg.CONF CONF 'backend', 'oslo.db.options', group='database') CONF.import_opt( = {'sqlalchemy': 'project.db.sqlalchemy.api'} _BACKEND_MAPPING = db_api.DBAPI(CONF.database.backend, backend_mapping=_BACKEND_MAPPING) IMPL def get_engine(): return IMPL.get_engine() def get_session(): return IMPL.get_session() # DB-API method def do_something(somethind_id): return IMPL.do_something(somethind_id)