Integrate playlist loader

Remove old playlist download code and use the playlist loader. Update test cases.

Integrate playlist loader
Remove old playlist download code and use the playlist loader. Update test cases.
David LaPalomento
Showing 4 changed files with 126 additions and 189 deletions
src/playlist-loader.js
src/videojs-hls.js
test/playlist-loader_test.js
test/videojs-hls_test.js
--- a/src/playlist-loader.js
View file @d8cf74c
+++ b/src/playlist-loader.js
View file @d8cf74c
@@ -47,7 +47,7 @@
      return changed ? result : null;
    },
-    PlaylistLoader = function(srcUrl) {
+    PlaylistLoader = function(srcUrl, withCredentials) {
      var
        loader = this,
        media,
@@ -92,6 +92,8 @@
              loader.trigger('mediaupdatetimeout');
            }, refreshDelay);
          }
+          loader.trigger('loadedplaylist');
        };
      PlaylistLoader.prototype.init.call(this);
@@ -122,13 +124,6 @@
        if (loader.state === 'HAVE_NOTHING' || loader.state === 'HAVE_MASTER') {
          throw new Error('Cannot switch media playlist from ' + loader.state);
        }
-        loader.state = 'SWITCHING_MEDIA';
-        // abort any outstanding playlist refreshes
-        if (request) {
-          request.abort();
-          request = null;
-        }
        // find the playlist object if the target playlist has been
        // specified by URI
@@ -139,8 +134,24 @@
          playlist = loader.master.playlists[playlist];
        }
+        if (playlist.uri === media.uri) {
+          // switching to the currently active playlist is a no-op
+          return;
+        }
+        loader.state = 'SWITCHING_MEDIA';
+        // abort any outstanding playlist refreshes
+        if (request) {
+          request.abort();
+          request = null;
+        }
        // request the new playlist
-        request = xhr(resolveUrl(loader.master.uri, playlist.uri), function(error) {
+        request = xhr({
+          url: resolveUrl(loader.master.uri, playlist.uri),
+          withCredentials: withCredentials
+        }, function(error) {
          haveMetadata(error, this, playlist.uri);
        });
      };
@@ -153,21 +164,26 @@
        }
        loader.state = 'HAVE_CURRENT_METADATA';
-        request = xhr(resolveUrl(loader.master.uri, loader.media().uri),
+        request = xhr({
-                      function(error) {
+          url: resolveUrl(loader.master.uri, loader.media().uri),
-                        haveMetadata(error, this, loader.media().uri);
+          withCredentials: withCredentials
-                      });
+        }, function(error) {
+          haveMetadata(error, this, loader.media().uri);
+        });
      });
      // request the specified URL
-      xhr(srcUrl, function(error) {
+      xhr({
+        url: srcUrl,
+        withCredentials: withCredentials
+      }, function(error) {
        var parser, i;
        if (error) {
          loader.error = {
            status: this.status,
            message: 'HLS playlist request error at URL: ' + srcUrl,
-            code: (this.status >= 500) ? 4 : 2
+            code: 2 // MEDIA_ERR_NETWORK
          };
          return loader.trigger('error');
        }
@@ -189,13 +205,16 @@
            loader.master.playlists[loader.master.playlists[i].uri] = loader.master.playlists[i];
          }
-          request = xhr(resolveUrl(srcUrl, parser.manifest.playlists[0].uri),
+          request = xhr({
-                        function(error) {
+            url: resolveUrl(srcUrl, parser.manifest.playlists[0].uri),
-                          // pass along the URL specified in the master playlist
+            withCredentials: withCredentials
-                          haveMetadata(error,
+          }, function(error) {
-                                       this,
+            // pass along the URL specified in the master playlist
-                                       parser.manifest.playlists[0].uri);
+            haveMetadata(error,
-                        });
+                         this,
+                         parser.manifest.playlists[0].uri);
+            loader.trigger('loadedmetadata');
+          });
          return loader.trigger('loadedplaylist');
        }
@@ -208,7 +227,8 @@
          }]
        };
        loader.master.playlists[srcUrl] = loader.master.playlists[0];
-        return haveMetadata(null, this, srcUrl);
+        haveMetadata(null, this, srcUrl);
+        return loader.trigger('loadedmetadata');
      });
    };
  PlaylistLoader.prototype = new videojs.hls.Stream();
--- a/src/videojs-hls.js
View file @d8cf74c
+++ b/src/videojs-hls.js
View file @d8cf74c
@@ -194,15 +194,20 @@ var
   */
  translateMediaIndex = function(mediaIndex, original, update) {
    var
-      i = update.segments.length,
+      i,
      originalSegment;
    // no segments have been loaded from the original playlist
    if (mediaIndex === 0) {
      return 0;
    }
+    if (!(update && update.segments)) {
+      // let the media index be zero when there are no segments defined
+      return 0;
+    }
    // try to sync based on URI
+    i = update.segments.length;
    originalSegment = original.segments[mediaIndex - 1];
    while (i--) {
      if (originalSegment.uri === update.segments[i].uri) {
@@ -292,12 +297,9 @@ var
      player = this,
      srcUrl,
-      playlistXhr,
      segmentXhr,
      settings,
-      loadedPlaylist,
      fillBuffer,
-      updateCurrentPlaylist,
      updateDuration;
    // if the video element supports HLS natively, do nothing
@@ -376,7 +378,8 @@ var
    player.on('seeking', function() {
      var currentTime = player.currentTime();
-      player.hls.mediaIndex = getMediaIndexByTime(player.hls.media, currentTime);
+      player.hls.mediaIndex = getMediaIndexByTime(player.hls.playlists.media(),
+                                                  currentTime);
      // abort any segments still being decoded
      player.hls.sourceBuffer.abort();
@@ -407,39 +410,6 @@ var
    };
    /**
-     * Determine whether the current media playlist should be changed
-     * and trigger a switch if necessary. If a sufficiently fresh
-     * version of the target playlist is available, the switch will take
-     * effect immediately. Otherwise, the target playlist will be
-     * refreshed.
-     */
-    updateCurrentPlaylist = function() {
-      var playlist, mediaSequence;
-      playlist = player.hls.selectPlaylist();
-      mediaSequence = player.hls.mediaIndex + (player.hls.media.mediaSequence || 0);
-      if (!playlist.segments ||
-          mediaSequence < (playlist.mediaSequence || 0) ||
-          mediaSequence > (playlist.mediaSequence || 0) + playlist.segments.length) {
-        if (playlistXhr) {
-          playlistXhr.abort();
-        }
-        playlistXhr = xhr({
-          url: resolveUrl(srcUrl, playlist.uri),
-          withCredentials: settings.withCredentials
-        }, loadedPlaylist);
-      } else {
-        player.hls.mediaIndex =
-          translateMediaIndex(player.hls.mediaIndex,
-                              player.hls.media,
-                              playlist);
-        player.hls.media = playlist;
-        updateDuration(player.hls.media);
-      }
-    };
-    /**
     * Chooses the appropriate media playlist based on the current
     * bandwidth estimate and the player size.
     * @return the highest bitrate playlist less than the currently detected
@@ -448,7 +418,7 @@ var
    player.hls.selectPlaylist = function () {
      var
        effectiveBitrate,
-        sortedPlaylists = player.hls.master.playlists.slice(),
+        sortedPlaylists = player.hls.playlists.master.playlists.slice(),
        bandwidthPlaylists = [],
        i = sortedPlaylists.length,
        variant,
@@ -513,97 +483,6 @@ var
    };
    /**
-     * Callback that is invoked when a media playlist finishes
-     * downloading. Triggers `loadedmanifest` once for each playlist
-     * that is downloaded and `loadedmetadata` after at least one
-     * media playlist has been parsed.
-     *
-     * @param error {*} truthy if the request was not successful
-     * @param url {string} a URL to the M3U8 file to process
-     */
-    loadedPlaylist = function(error, url) {
-      var i, parser, playlist, playlistUri, refreshDelay;
-      // clear the current playlist XHR
-      playlistXhr = null;
-      if (error) {
-        player.hls.error = {
-          status: this.status,
-          message: 'HLS playlist request error at URL: ' + url,
-          code: (this.status >= 500) ? 4 : 2
-        };
-        return player.trigger('error');
-      }
-      parser = new videojs.m3u8.Parser();
-      parser.push(this.responseText);
-      // merge this playlist into the master
-      i = player.hls.master.playlists.length;
-      refreshDelay = (parser.manifest.targetDuration || 10) * 1000;
-      while (i--) {
-        playlist = player.hls.master.playlists[i];
-        playlistUri = resolveUrl(srcUrl, playlist.uri);
-        if (playlistUri === url) {
-          // if the playlist is unchanged since the last reload,
-          // try again after half the target duration
-          // http://tools.ietf.org/html/draft-pantos-http-live-streaming-12#section-6.3.4
-          if (playlist.segments &&
-              playlist.segments.length === parser.manifest.segments.length) {
-            refreshDelay /= 2;
-          }
-          player.hls.master.playlists[i] =
-            videojs.util.mergeOptions(playlist, parser.manifest);
-          if (playlist !== player.hls.media) {
-            continue;
-          }
-          // determine the new mediaIndex if we're updating the
-          // current media playlist
-          player.hls.mediaIndex =
-            translateMediaIndex(player.hls.mediaIndex,
-                                playlist,
-                                parser.manifest);
-          player.hls.media = parser.manifest;
-        }
-      }
-      // check the playlist for updates if EXT-X-ENDLIST isn't present
-      if (!parser.manifest.endList) {
-        window.setTimeout(function() {
-          if (!playlistXhr &&
-              resolveUrl(srcUrl, player.hls.media.uri) === url) {
-            playlistXhr = xhr(url, loadedPlaylist);
-          }
-        }, refreshDelay);
-      }
-      // always start playback with the default rendition
-      if (!player.hls.media) {
-        player.hls.media = player.hls.master.playlists[0];
-        // update the duration
-        updateDuration(parser.manifest);
-        // periodicaly check if the buffer needs to be refilled
-        player.on('timeupdate', fillBuffer);
-        player.trigger('loadedmanifest');
-        player.trigger('loadedmetadata');
-        fillBuffer();
-        return;
-      }
-      // select a playlist and download its metadata if necessary
-      updateCurrentPlaylist();
-      player.trigger('loadedmanifest');
-    };
-    /**
     * Determines whether there is enough video data currently in the buffer
     * and downloads a new segment if the buffered time is less than the goal.
     * @param offset (optional) {number} the offset into the downloaded segment
@@ -623,12 +502,12 @@ var
      }
      // if no segments are available, do nothing
-      if (!player.hls.media.segments) {
+      if (!player.hls.playlists.media().segments) {
        return;
      }
      // if the video has finished downloading, stop trying to buffer
-      segment = player.hls.media.segments[player.hls.mediaIndex];
+      segment = player.hls.playlists.media().segments[player.hls.mediaIndex];
      if (!segment) {
        return;
      }
@@ -644,10 +523,10 @@ var
      }
      // resolve the segment URL relative to the playlist
-      if (player.hls.media.uri === srcUrl) {
+      if (player.hls.playlists.media().uri === srcUrl) {
        segmentUri = resolveUrl(srcUrl, segment.uri);
      } else {
-        segmentUri = resolveUrl(resolveUrl(srcUrl, player.hls.media.uri || ''),
+        segmentUri = resolveUrl(resolveUrl(srcUrl, player.hls.playlists.media().uri || ''),
                                segment.uri);
      }
@@ -708,49 +587,55 @@ var
        player.hls.mediaIndex++;
-        if (player.hls.mediaIndex === player.hls.media.segments.length) {
+        if (player.hls.mediaIndex === player.hls.playlists.media().segments.length) {
          mediaSource.endOfStream();
        }
        // figure out what stream the next segment should be downloaded from
        // with the updated bandwidth information
-        updateCurrentPlaylist();
+        player.hls.playlists.media(player.hls.selectPlaylist());
      });
    };
    // load the MediaSource into the player
    mediaSource.addEventListener('sourceopen', function() {
      // construct the video data buffer and set the appropriate MIME type
-      var sourceBuffer = mediaSource.addSourceBuffer('video/flv; codecs="vp6,aac"');
+      var
+        sourceBuffer = mediaSource.addSourceBuffer('video/flv; codecs="vp6,aac"'),
+        oldMediaPlaylist;
      player.hls.sourceBuffer = sourceBuffer;
      sourceBuffer.appendBuffer(segmentParser.getFlvHeader());
      player.hls.mediaIndex = 0;
-      xhr({
+      player.hls.playlists =
-        url: srcUrl,
+        new videojs.hls.PlaylistLoader(srcUrl, settings.withCredentials);
-        withCredentials: settings.withCredentials
+      player.hls.playlists.on('loadedmetadata', function() {
-      }, function(error, url) {
+        oldMediaPlaylist = player.hls.playlists.media();
-        var uri, parser = new videojs.m3u8.Parser();
-        parser.push(this.responseText);
+        // periodicaly check if the buffer needs to be refilled
+        fillBuffer();
-        // master playlists
+        player.on('timeupdate', fillBuffer);
-        if (parser.manifest.playlists) {
-          player.hls.master = parser.manifest;
+        player.trigger('loadedmetadata');
-          playlistXhr = xhr({
+      });
-            url: resolveUrl(url, parser.manifest.playlists[0].uri),
+      player.hls.playlists.on('error', function() {
-            withCredentials: settings.withCredentials
+        player.hls.error = player.hls.playlists.error;
-          }, loadedPlaylist);
+        player.trigger('error');
-          return player.trigger('loadedmanifest');
+      });
-        } else {
+      player.hls.playlists.on('loadedplaylist', function() {
-          // infer a master playlist if a media playlist is loaded directly
+        var updatedPlaylist = player.hls.playlists.media();
-          uri = resolveUrl(window.location.href, url);
-          player.hls.master = {
+        if (!updatedPlaylist) {
-            playlists: [{
+          // do nothing before an initial media playlist has been activated
-              uri: uri
+          return;
-            }]
-          };
-          loadedPlaylist.call(this, error, uri);
        }
+        updateDuration(player.hls.playlists.media());
+        player.hls.mediaIndex = translateMediaIndex(player.hls.mediaIndex,
+                                                    oldMediaPlaylist,
+                                                    updatedPlaylist);
+        oldMediaPlaylist = updatedPlaylist;
      });
    });
    player.src([{
--- a/test/playlist-loader_test.js
View file @d8cf74c
+++ b/test/playlist-loader_test.js
View file @d8cf74c
@@ -65,7 +65,12 @@
  });
  test('jumps to HAVE_METADATA when initialized with a media playlist', function() {
-    var loader = new videojs.hls.PlaylistLoader('media.m3u8');
+    var
+      loadedmetadatas = 0,
+      loader = new videojs.hls.PlaylistLoader('media.m3u8');
+    loader.on('loadedmetadata', function() {
+      loadedmetadatas++;
+    });
    requests.pop().respond(200, null,
                           '#EXTM3U\n' +
                           '#EXTINF:10,\n' +
@@ -75,7 +80,8 @@
    ok(loader.media(), 'sets the media playlist');
    ok(loader.media().uri, 'sets the media playlist URI');
    strictEqual(loader.state, 'HAVE_METADATA', 'the state is correct');
-    strictEqual(0, requests.length, 'no more requests are made');
+    strictEqual(requests.length, 0, 'no more requests are made');
+    strictEqual(loadedmetadatas, 1, 'fired one loadedmetadata');
  });
  test('jumps to HAVE_METADATA when initialized with a live media playlist', function() {
@@ -91,17 +97,22 @@
  test('moves to HAVE_METADATA after loading a media playlist', function() {
    var
-      loadedPlaylist = false,
+      loadedPlaylist = 0,
+      loadedMetadata = 0,
      loader = new videojs.hls.PlaylistLoader('master.m3u8');
    loader.on('loadedplaylist', function() {
-      loadedPlaylist = true;
+      loadedPlaylist++;
+    });
+    loader.on('loadedmetadata', function() {
+      loadedMetadata++;
    });
    requests.pop().respond(200, null,
                           '#EXTM3U\n' +
                           '#EXT-X-STREAM-INF:\n' +
                           'media.m3u8\n' +
                           'alt.m3u8\n');
-    ok(loadedPlaylist, 'loadedplaylist fired');
+    strictEqual(loadedPlaylist, 1, 'fired loadedplaylist once');
+    strictEqual(loadedMetadata, 0, 'did not fire loadedmetadata');
    strictEqual(requests.length, 1, 'requests the media playlist');
    strictEqual(requests[0].method, 'GET', 'GETs the media playlist');
    strictEqual(requests[0].url,
@@ -114,6 +125,8 @@
                           '0.ts\n');
    ok(loader.master, 'sets the master playlist');
    ok(loader.media(), 'sets the media playlist');
+    strictEqual(loadedPlaylist, 2, 'fired loadedplaylist twice');
+    strictEqual(loadedMetadata, 1, 'fired loadedmetadata once');
    strictEqual(loader.state, 'HAVE_METADATA', 'the state is correct');
  });
@@ -317,6 +330,25 @@
    strictEqual(loader.state, 'SWITCHING_MEDIA', 'updated the state');
  });
+  test('switching to the active playlist is a no-op', function() {
+    var loader = new videojs.hls.PlaylistLoader('master.m3u8');
+    requests.pop().respond(200, null,
+                           '#EXTM3U\n' +
+                           '#EXT-X-STREAM-INF:BANDWIDTH=1\n' +
+                           'low.m3u8\n' +
+                           '#EXT-X-STREAM-INF:BANDWIDTH=2\n' +
+                           'high.m3u8\n');
+    requests.pop().respond(200, null,
+                           '#EXTM3U\n' +
+                           '#EXT-X-MEDIA-SEQUENCE:0\n' +
+                           '#EXTINF:10,\n' +
+                           'low-0.ts\n' +
+                           '#EXT-X-ENDLIST\n');
+    loader.media('low.m3u8');
+    strictEqual(requests.length, 0, 'no requests is sent');
+  });
  test('throws an error if a media switch is initiated too early', function() {
    var loader = new videojs.hls.PlaylistLoader('master.m3u8');
--- a/test/videojs-hls_test.js
View file @d8cf74c
+++ b/test/videojs-hls_test.js
View file @d8cf74c