feat(HLS): Add the update period for HLS manifest (#7498)

Create the update period for hls parse

Close #7505

demo/config.js

@@ -268,7 +268,9 @@ shakaDemo.Config = class {
         .addBoolInput_('Disable closed caption detection',
             'manifest.hls.disableClosedCaptionsDetection')
         .addBoolInput_('Allow LL-HLS byterange optimization',
-            'manifest.hls.allowLowLatencyByteRangeOptimization');
+            'manifest.hls.allowLowLatencyByteRangeOptimization')
+        .addNumberInput_('override the Update time of the manifest',
+            'manifest.hls.updatePeriod');
   }
 
   /** @private */

externs/shaka/player.js

@@ -1179,10 +1179,10 @@ shaka.extern.xml.Node;
  *   <br>
  *   Defaults to <code>false</code>.
  * @property {number} updatePeriod
- *   Override the minimumUpdatePeriod of the manifest. The value is in second
- *   if the value is greater than the minimumUpdatePeriod, it will update the
- *   manifest less frequently. if you update the value during for a dynamic
- *   manifest, it will directly trigger a new download of the manifest
+ *   Override the minimumUpdatePeriod of the manifest. The value is in seconds.
+ *   If the value is greater than the minimumUpdatePeriod, it will update the
+ *   manifest less frequently. If you update the value during for a dynamic
+ *   manifest, it will directly trigger a new download of the manifest.
  *   <br>
  *   Defaults to <code>-1</code>.
  * @property {boolean} enableFastSwitching
@@ -1208,7 +1208,8 @@ shaka.extern.DashManifestConfiguration;
  *   ignoreManifestTimestampsInSegmentsMode: boolean,
  *   disableCodecGuessing: boolean,
  *   disableClosedCaptionsDetection: boolean,
- *   allowLowLatencyByteRangeOptimization: boolean
+ *   allowLowLatencyByteRangeOptimization: boolean,
+ *   updatePeriod: number
  * }}
  *
  * @property {boolean} ignoreTextStreamFailures
@@ -1294,6 +1295,14 @@ shaka.extern.DashManifestConfiguration;
  *   https://www.akamai.com/blog/performance/-using-ll-hls-with-byte-range-addressing-to-achieve-interoperabi
  *   <br>
  *   Defaults to <code>true</code>.
+ * @property {number} updatePeriod
+ *   Override the update period of the playlist. The value is in seconds.
+ *   If the value is less than 0, the period will be determined based on the
+ *   segment length.  If the value is greater than 0, it will update the target
+ *   duration.  If you update the value during the live, it will directly
+ *   trigger a new download of the manifest.
+ *   <br>
+ *   Defaults to <code>-1</code>.
  * @exportDoc
  */
 shaka.extern.HlsManifestConfiguration;

lib/hls/hls_parser.js

@@ -293,6 +293,9 @@ shaka.hls.HlsParser = class {
    * @exportInterface
    */
   configure(config, isPreloadFn) {
+    const needFireUpdate = this.playerInterface_ &&
+      config.hls.updatePeriod != this.config_.hls.updatePeriod &&
+      config.hls.updatePeriod >= 0;
     this.config_ = config;
     if (isPreloadFn) {
       this.isPreloadFn_ = isPreloadFn;
@@ -301,6 +304,11 @@ shaka.hls.HlsParser = class {
     if (this.contentSteeringManager_) {
       this.contentSteeringManager_.configure(this.config_);
     }
+
+    if (needFireUpdate && this.manifest_ &&
+      this.manifest_.presentationTimeline.isLive()) {
+      this.updatePlaylistTimer_.tickNow();
+    }
   }
 
   /**
@@ -4587,7 +4595,8 @@ shaka.hls.HlsParser = class {
       if (this.isLive_()) {
         const updateDuration = (endTime - startTime) / 1000.0;
         this.averageUpdateDuration_.sample(1, updateDuration);
-        const delay = this.getUpdatePlaylistDelay_();
+        const delay = this.config_.hls.updatePeriod > 0 ?
+            this.config_.hls.updatePeriod : this.getUpdatePlaylistDelay_();
         const finalDelay = Math.max(0,
             delay - this.averageUpdateDuration_.getEstimate());
         this.updatePlaylistTimer_.tickAfter(/* seconds= */ finalDelay);

lib/util/player_configuration.js

@@ -173,6 +173,7 @@ shaka.util.PlayerConfiguration = class {
         ignoreManifestTimestampsInSegmentsMode: false,
         disableCodecGuessing: false,
         disableClosedCaptionsDetection: false,
+        updatePeriod: -1,
         allowLowLatencyByteRangeOptimization: true,
       },
       mss: {