'Get all snapshot given some search_opts (filters).
Special filters accepted are host and cluster_name, that refer to the
volume\'s fields.'

@classmethod
def get_all(cls, context, filters, marker=None, limit=None, sort_keys=None, sort_dirs=None, offset=None):

    snapshots = db.snapshot_get_all(context, filters, marker, limit, sort_keys, sort_dirs, offset)
    expected_attrs = Snapshot._get_expected_attrs(context)
    return base.obj_make_list(context, cls(context), objects.Snapshot, snapshots, expected_attrs=expected_attrs)
