sqlalchemydb.py 文件源码

def getEngine(uri, **kwargs):
    """
    Get a sqlalchemy engine from a pool in case we use the same parameters for
    multiple connections.
    """
    key = (uri, frozenset(six.viewitems(kwargs)))
    engine = _enginePool.get(key)
    if engine is None:
        engine = sqlalchemy.create_engine(uri, **kwargs)
        if len(_enginePool) >= _enginePoolMaxSize:
            _enginePoolMaxSize.clear()
        _enginePool[key] = engine
    return engine