def setUp(self):
        super(RootReadWriteVolumeGatewayTestCase, self).setUp()
        self.gw = SystemGateway()
        user = self.factory.make_user()
        self.user = self.gw.get_user(user.id, session_id='QWERTY')
        # make a test file
        vgw = self.user._gateway.get_root_gateway()
        root = StorageObject.objects.get(id=vgw.get_root().id)
        self.file = root.make_file(
            'TheName', content_blob=self.factory.make_content_blob(),
            mimetype='fakemime')