chrome/test/data/webrtc/getusermedia.js

   1 /**
   2  * Copyright (c) 2012 The Chromium Authors. All rights reserved.
   3  * Use of this source code is governed by a BSD-style license that can be
   4  * found in the LICENSE file.
   5  */
   6
   7 /**
   8  * See http://dev.w3.org/2011/webrtc/editor/getusermedia.html for more
   9  * information on getUserMedia.
  10  */
  11
  12 /**
  13  * Keeps track of our local stream (e.g. what our local webcam is streaming).
  14  * @private
  15  */
  16 var gLocalStream = null;
  17
  18 /**
  19  * The MediaConstraints to use when connecting the local stream with a peer
  20  * connection.
  21  * @private
  22  */
  23 var gAddStreamConstraints = {};
  24
  25 /**
  26  * String which keeps track of what happened when we requested user media.
  27  * @private
  28  */
  29 var gRequestWebcamAndMicrophoneResult = 'not-called-yet';
  30
  31 /**
  32  * Used as a shortcut. Moved to the top of the page due to race conditions.
  33  * @param {string} id is a case-sensitive string representing the unique ID of
  34  *     the element being sought.
  35  * @return {string} id returns the element object specified as a parameter
  36  */
  37 $ = function(id) {
  38   return document.getElementById(id);
  39 };
  40
  41 /**
  42  * This function asks permission to use the webcam and mic from the browser. It
  43  * will return ok-requested to the test. This does not mean the request was
  44  * approved though. The test will then have to click past the dialog that
  45  * appears in Chrome, which will run either the OK or failed callback as a
  46  * a result. To see which callback was called, use obtainGetUserMediaResult().
  47  *
  48  * @param {!object} constraints Defines what to be requested, with mandatory
  49  *     and optional constraints defined. The contents of this parameter depends
  50  *     on the WebRTC version.
  51  */
  52 function doGetUserMedia(constraints) {
  53   if (!getUserMedia) {
  54     returnToTest('Browser does not support WebRTC.');
  55     return;
  56   }
  57   debug('Requesting doGetUserMedia: constraints: ' + constraints);
  58   getUserMedia(constraints,
  59                function(stream) {
  60                  ensureGotAllExpectedStreams_(stream, constraints);
  61                  getUserMediaOkCallback_(stream);
  62                },
  63                getUserMediaFailedCallback_);
  64   returnToTest('ok-requested');
  65 }
  66
  67 /**
  68  * Must be called after calling doGetUserMedia.
  69  * @return {string} Returns not-called-yet if we have not yet been called back
  70  *     by WebRTC. Otherwise it returns either ok-got-stream or
  71  *     failed-with-error-x (where x is the error code from the error
  72  *     callback) depending on which callback got called by WebRTC.
  73  */
  74 function obtainGetUserMediaResult() {
  75   returnToTest(gRequestWebcamAndMicrophoneResult);
  76   return gRequestWebcamAndMicrophoneResult;
  77 }
  78
  79 /**
  80  * Stops all tracks of the last acquired local stream.
  81  */
  82 function stopLocalStream() {
  83   if (gLocalStream == null)
  84     throw failTest('Tried to stop local stream, ' +
  85                    'but media access is not granted.');
  86
  87   gLocalStream.getVideoTracks().forEach(function(track) {
  88     track.stop();
  89   });
  90   gLocalStream.getAudioTracks().forEach(function(track) {
  91     track.stop();
  92   });
  93   gLocalStream = null;
  94   gRequestWebcamAndMicrophoneResult = 'not-called-yet';
  95   returnToTest('ok-stopped');
  96 }
  97
  98 // Functions callable from other JavaScript modules.
  99
 100 /**
 101  * Adds the current local media stream to a peer connection.
 102  * @param {RTCPeerConnection} peerConnection
 103  */
 104 function addLocalStreamToPeerConnection(peerConnection) {
 105   if (gLocalStream == null)
 106     throw failTest('Tried to add local stream to peer connection, ' +
 107                    'but there is no stream yet.');
 108   try {
 109     peerConnection.addStream(gLocalStream, gAddStreamConstraints);
 110   } catch (exception) {
 111     throw failTest('Failed to add stream with constraints ' +
 112                    gAddStreamConstraints + ': ' + exception);
 113   }
 114   debug('Added local stream.');
 115 }
 116
 117 /**
 118  * @return {string} Returns the current local stream - |gLocalStream|.
 119  */
 120 function getLocalStream() {
 121   return gLocalStream;
 122 }
 123
 124 // Internals.
 125
 126 /**
 127  * @private
 128  * @param {!MediaStream} stream Media stream from getUserMedia.
 129  * @param {!object} constraints The getUserMedia constraints object.
 130  */
 131 function ensureGotAllExpectedStreams_(stream, constraints) {
 132   if (constraints['video'] && stream.getVideoTracks().length == 0) {
 133     gRequestWebcamAndMicrophoneResult = 'failed-to-get-video';
 134     throw ('Requested video, but did not receive a video stream from ' +
 135            'getUserMedia. Perhaps the machine you are running on ' +
 136            'does not have a webcam.');
 137   }
 138   if (constraints['audio'] && stream.getAudioTracks().length == 0) {
 139     gRequestWebcamAndMicrophoneResult = 'failed-to-get-audio';
 140     throw ('Requested audio, but did not receive an audio stream ' +
 141            'from getUserMedia. Perhaps the machine you are running ' +
 142            'on does not have audio devices.');
 143   }
 144 }
 145
 146 /**
 147  * @private
 148  * @param {MediaStream} stream Media stream.
 149  */
 150 function getUserMediaOkCallback_(stream) {
 151   gLocalStream = stream;
 152   gRequestWebcamAndMicrophoneResult = 'ok-got-stream';
 153
 154   attachMediaStream($('local-view'), stream);
 155 }
 156
 157 /**
 158  * @private
 159  * @param {NavigatorUserMediaError} error Error containing details.
 160  */
 161 function getUserMediaFailedCallback_(error) {
 162   // Translate from the old error to the new. Remove when rename fully deployed.
 163   var errorName = error.name;
 164
 165   debug('GetUserMedia FAILED: Maybe the camera is in use by another process?');
 166   gRequestWebcamAndMicrophoneResult = 'failed-with-error-' + errorName;
 167   debug(gRequestWebcamAndMicrophoneResult);
 168 }