'Stop managing a snapshot.
This action is very much like a delete, except that a different
method (unmanage) is called on the Cinder driver.  This has the effect
of removing the snapshot from Cinder management without actually
removing the backend storage object associated with it.
There are no required parameters.
A Not Found error is returned if the specified snapshot does not exist.'

@wsgi.response(http_client.ACCEPTED)
@wsgi.action('os-unmanage')
def unmanage(self, req, id, body):

    context = req.environ['cinder.context']
    authorize(context)
    LOG.info('Unmanage    snapshot    with    id:    %s', id)
    try:
        snapshot = self.volume_api.get_snapshot(context, id)
        self.volume_api.delete_snapshot(context, snapshot, unmanage_only=True)
    except exception.InvalidSnapshot as ex:
        raise exc.HTTPBadRequest(explanation=ex.msg)
    return webob.Response(status_int=http_client.ACCEPTED)
