tag.py 文件源码

def delete(self, paths):
        """Delete L{Tag}s matching C{paths}.

        L{TagValue}s and permissions associated with the deleted L{Tag}s are
        removed by cascading deletes in the database schema.

        @param paths: A sequence of L{Tag.path}s.
        @return: A C{list} of C{(objectID, Tag.path)} 2-tuples representing the
            L{Tag}s that were removed.
        """
        if isgenerator(paths):
            paths = list(paths)
        result = getTags(paths=paths)
        deletedTagPaths = list(result.values(Tag.objectID, Tag.path))
        # Delete the fluiddb/tags/description tag values stored for removed
        # tags.  Associated TagValue's are removed by an ON DELETE CASCADE
        # trigger.
        self._factory.tagValues(self._user).delete(
            [(objectID, path) for objectID, _ in deletedTagPaths
             for path in [u'fluiddb/tags/description', u'fluiddb/tags/path']])

        # Touch all the objects for the given tag paths.
        objectIDs = list(getObjectIDs(paths))
        touchObjects(objectIDs)

        result.remove()
        return deletedTagPaths