Kurento pipeline which only one audio records.

gistfile1.js

exports.createCompositePipeline = function(hostSdpOffer, guestSdpOffer, callback) {
  if (callback == null) {
    callback = function() {};
  }
  console.log("Creating call pipeline");
  return client.create('MediaPipeline', function(err, pipeline) {
    return pipeline.create('WebRtcEndpoint', function(err, hostWebRtcEndpoint) {
      return pipeline.create('WebRtcEndpoint', function(err, guestWebRtcEndpoint) {
        return pipeline.create('Composite', function(err, composite) {
          return composite.createHubPort(function(err, guestHubPort) {
            return composite.createHubPort(function(err, hostHubPort) {
              return hostWebRtcEndpoint.connect(hostHubPort, function() {
                return guestWebRtcEndpoint.connect(guestHubPort, function() {
                  return hostHubPort.connect(hostWebRtcEndpoint, function() {
                    return guestHubPort.connect(guestWebRtcEndpoint, function() {
                      return hostWebRtcEndpoint.processOffer(hostSdpOffer, function(err, hostAnswer) {
                        return guestWebRtcEndpoint.processOffer(guestSdpOffer, function(err, guestAnswer) {
                          console.log("Sending host answer back.");
                          callback(err, hostAnswer, guestAnswer);
                          return pipeline.create('RecorderEndpoint', {
                            uri: "file:///tmp/movie_recordings/composite_sample_clip_" + (getFilename()) + ".webm"
                          }, function(err, _recorder) {
                            return hostHubPort.connect(_recorder, function() {
                              console.log("probably connected everything correctly?");
                              return _recorder.record(function() {
                                return console.log("probably recording??");
                              });
                            });
                          });
                        });
                      });
                    });
                  });
                });
              });
            });
          });
        });
      });
    });
  });
};

https://s3.amazonaws.com/media.vidpresso.com/uploads/1437146359546-mj1t0fk78v1b57b9-f1e211178edfcd42cb13b4e9c1e0324a/composite_sample_clip_980.webm