How to record a video using webrtc

I need to record a video using the laptop camera on my website built using nodejs. For this I am using webRTC. So far I could take a photo using the laptop camera but I need to record a video. Could some one help as to how the code would go? My current code is as follows:

<video id="video"></video>
<button id="startbutton">Take photo</button>
<button id="pausebutton">Pause</button>
<button id="resumebutton">Resume</button>
<canvas id="canvas"></canvas>

<script type="text/javascript">
(function() {

  var streaming = false,
      video        = document.querySelector('#video'),
      canvas       = document.querySelector('#canvas'),
      //photo        = document.querySelector('#photo'),
      startbutton  = document.querySelector('#startbutton'),
      width = 620,
      height = 50;

  navigator.getMedia = ( navigator.getUserMedia ||
                         navigator.webkitGetUserMedia ||
                         navigator.mozGetUserMedia ||
                         navigator.msGetUserMedia);

  navigator.getMedia(
    {
      video: true,
      audio: false
    },
    function(stream) {
      if (navigator.mozGetUserMedia) {
        video.mozSrcObject = stream;
      } else {
        var vendorURL = window.URL || window.webkitURL;
        video.src = vendorURL.createObjectURL(stream);
      }
      video.play();
    },
    function(err) {
      console.log("An error occured! " + err);
    }
  );

  video.addEventListener('canplay', function(ev){
    if (!streaming) {
      height = video.videoHeight / (video.videoWidth/width);
      video.setAttribute('width', width);
      video.setAttribute('height', height);
      canvas.setAttribute('width', width);
      canvas.setAttribute('height', height);
      streaming = true;
    }
  }, false);

  function takepicture() {
    canvas.width = width;
    canvas.height = height;
    canvas.getContext('2d').drawImage(video, 0, 0, width, height);
    var data = canvas.toDataURL('image/png');
   // photo.setAttribute('src', data);
  }


  function pausevideo() {
    canvas.width = width;
    canvas.height = height;
    video.pause();
  }
  function resumevideo() {
    canvas.width = width;
    canvas.height = height;
    video.play();
  }


  startbutton.addEventListener('click', function(ev){
      takepicture();
    ev.preventDefault();
  }, false);

  pausebutton.addEventListener('click', function(ev){
      pausevideo();
    ev.preventDefault();
  }, false);

  resumebutton.addEventListener('click', function(ev){
      resumevideo();
    ev.preventDefault();
  }, false);


})();
</script>

I am not going to write code for you(you seem pretty capable if you have gotten this far) but here are some pointers to get you in the right direction.

Assign a global variable the value of the stream when you grab it(this way you can reuse the same stream in numerous functions
Once you have the stream you can easily follow the tutorials at RTC-Recording, there is a write to disk method that should help you out in downloading the recording

If you have a stream, this is how to start using RecordRTC.

   var options = {
      type: 'video'
    };
    var recordRTC = RecordRTC(mediaStream, options);
    recordRTC.startRecording();
    recordRTC.stopRecording(function(videoURL) {
        mediaElement.src = videoURL; //plays the recorded blob url on that src
    });