third_party/WebKit/LayoutTests/http/tests/media/progress-events-generated-correctly.html

   1 <video controls></video>
   2 <p>Test that progress events are generated during loading of media resource.</p>
   3 <script src=../../media-resources/video-test.js></script>
   4 <script src=../../media-resources/media-file.js></script>
   5 <script>
   6     waitForEventAndFail('error');
   7
   8     // Given long enough duration, We should not reach ended playback state.
   9     waitForEventAndFail('ended');
  10
  11     // Tuned throttling should not induce player stall or suspended load.
  12     waitForEventAndFail('stalled');
  13     waitForEventAndFail('suspend');
  14     waitForEventAndFail('waiting');
  15
  16     var progressCount = 0;
  17     var lastProgressEventTime = 0;
  18     function progressListener(event)
  19     {
  20         // Implementations can vary the frequency within tolerance, so we must protect against flaky logs.
  21         // Remain silent here unless failure detected.
  22         if (video.networkState != HTMLMediaElement.NETWORK_LOADING) {
  23             failTest('Unexpected networkState ' + video.networkState +
  24                      ' when handling \'progress\' event. Is fetch completed or suspending?');
  25             return;
  26         }
  27
  28         progressCount++;
  29         lastProgressEventTime = window.performance.now();
  30     };
  31     video.addEventListener('progress', progressListener);
  32
  33     function canplayListener(event)
  34     {
  35         // Begin video playback to mitigate flakiness due to implementations suspending loads
  36         // on limited buffer capacity.
  37         video.play();
  38         video.removeEventListener('canplay', canplayListener);
  39     }
  40     video.addEventListener('canplay', canplayListener);
  41
  42     var progressCountAtLastCheck = 0;
  43     var checkCount = 0;
  44     // Spec requires 350ms +/- 200ms minimum 'progress' event interval when loading.
  45     var maxProgressFiringIntervalInMS = 550;
  46     // Multiple 'progress' events may fire within spec's tolerance window.
  47     var maxProgressCountIncrease = 3;
  48     function checkProgressCount()
  49     {
  50         checkCount++;
  51
  52         // Implementations can vary the frequency within tolerance, so we must protect against flakiness.
  53         // Keep progressCount values involved in checks here out of report unless failure detected.
  54         consoleWrite('Interval ' + checkCount + ' has elapsed. Checking progress event count delta.');
  55         var progressCountDelta = progressCount - progressCountAtLastCheck;
  56         if (progressCountDelta <= 0) {
  57             failTest('progressCount (' + progressCount + ') did not increase since the last check.');
  58             return;
  59         }
  60
  61         var surplusProgress = progressCountDelta - maxProgressCountIncrease;
  62         if (surplusProgress > 0) {
  63             failTest('Received at least ' + surplusProgress + ' too many progress event(s) since the last check.');
  64             return;
  65         }
  66
  67         if (checkCount == 3) {
  68             endTest();
  69             return;
  70         }
  71
  72         progressCountAtLastCheck = progressCount;
  73         var msSinceLastProgressEvent = window.performance.now() - lastProgressEventTime;
  74         var msUntilNextCheck = maxProgressFiringIntervalInMS - msSinceLastProgressEvent;
  75
  76         if (msUntilNextCheck <= 0) {
  77             failTest('ProgressCheck scheduling error: msUntilNextCheck is ' + msUntilNextCheck);
  78             return;
  79         }
  80
  81         setTimeout(checkProgressCount, msUntilNextCheck);
  82     }
  83
  84     waitForEvent('loadstart', function()
  85     {
  86         // No 'progress' event should fire prior to 'loadstart'.
  87         testExpected('progressCount', 0, '==');
  88         setTimeout(checkProgressCount, maxProgressFiringIntervalInMS);
  89     });
  90
  91     var mediaFile = findMediaFile('video', 'resources/test');
  92     var mimeType = mimeTypeForFile(mediaFile);
  93     // Assumes minimum file size selected is > 100 kB.
  94     // At least 4*maxProgressFiringIntervalInMS is how long we want to stretch the full
  95     // loading, because we perform checks after 3 of these intervals while still
  96     // loading. 100 kB over 2.2 seconds is 45 kBps.
  97     var kBps = 45;
  98
  99     video.src = 'video-throttled-load.cgi' + '?name=' + mediaFile + '&throttle=' + kBps + '&type=' + mimeType;
 100 </script>