docs: function(params, cb) {
      cb = cb || _noop;
      assert(params.topic);
  
      _metaBroker.metadata([params.topic], function(err, cluster) {
        cluster.topics.forEach(function(topic) {
          _partitions[topic.topicName] = topic.partitions;
        });
  
        cb(err, cluster);
      });
    }