fix(HLS): Avoid duplicate AES requests (#6399)

Fixes #6407
shaka-project · Apr 5, 2024 · ea740ba · ea740ba
1 parent 0fc5814
commit ea740ba
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Showing 3 changed files with 29 additions and 16 deletions.
diff --git a/lib/hls/hls_parser.js b/lib/hls/hls_parser.js
@@ -219,7 +219,10 @@ shaka.hls.HlsParser = class {
     /** @private {Map.<string, !shaka.extern.aesKey>} */
     this.aesKeyInfoMap_ = new Map();
 
-    /** @private {Map.<string, string>} */
+    /** @private {Map.<string, !Promise.<shaka.extern.Response>>} */
+    this.aesKeyMap_ = new Map();
+
+    /** @private {Map.<string, !Promise.<shaka.extern.Response>>} */
     this.identityKeyMap_ = new Map();
 
     /** @private {Map.<!shaka.media.InitSegmentReference, ?string>} */
@@ -306,6 +309,7 @@ shaka.hls.HlsParser = class {
     this.globalVariables_.clear();
     this.mapTagToInitSegmentRefMap_.clear();
     this.aesKeyInfoMap_.clear();
+    this.aesKeyMap_.clear();
     this.identityKeyMap_.clear();
     this.identityKidMap_.clear();
 
@@ -2926,11 +2930,15 @@ shaka.hls.HlsParser = class {
         const keyUris = shaka.hls.Utils.constructSegmentUris(
             getUris(), drmTag.getRequiredAttrValue('URI'), variables);
 
-        const requestType = shaka.net.NetworkingEngine.RequestType.KEY;
-        const request = shaka.net.NetworkingEngine.makeRequest(
-            keyUris, this.config_.retryParameters);
-        const keyResponse =
-            await this.makeNetworkRequest_(request, requestType);
+        const keyMapKey = keyUris.sort().join('');
+        if (!this.aesKeyMap_.has(keyMapKey)) {
+          const requestType = shaka.net.NetworkingEngine.RequestType.KEY;
+          const request = shaka.net.NetworkingEngine.makeRequest(
+              keyUris, this.config_.retryParameters);
+          const keyResponse = this.makeNetworkRequest_(request, requestType);
+          this.aesKeyMap_.set(keyMapKey, keyResponse);
+        }
+        const keyResponse = await this.aesKeyMap_.get(keyMapKey);
 
         // keyResponse.status is undefined when URI is "data:text/plain;base64,"
         if (!keyResponse.data ||
@@ -4264,20 +4272,16 @@ shaka.hls.HlsParser = class {
     const keyUris = shaka.hls.Utils.constructSegmentUris(
         getUris(), drmTag.getRequiredAttrValue('URI'), variables);
 
-    let key;
     const keyMapKey = keyUris.sort().join('');
-    if (this.identityKeyMap_.has(keyMapKey)) {
-      key = this.identityKeyMap_.get(keyMapKey);
-    } else {
+    if (!this.identityKeyMap_.has(keyMapKey)) {
       const requestType = shaka.net.NetworkingEngine.RequestType.KEY;
       const request = shaka.net.NetworkingEngine.makeRequest(
           keyUris, this.config_.retryParameters);
-      const keyResponse =
-          await this.makeNetworkRequest_(request, requestType);
-
-      key = shaka.util.Uint8ArrayUtils.toHex(keyResponse.data);
-      this.identityKeyMap_.set(keyMapKey, key);
+      const keyResponse = this.makeNetworkRequest_(request, requestType);
+      this.identityKeyMap_.set(keyMapKey, keyResponse);
     }
+    const keyResponse = await this.identityKeyMap_.get(keyMapKey);
+    const key = shaka.util.Uint8ArrayUtils.toHex(keyResponse.data);
 
     // NOTE: The ClearKey CDM requires a key-id to key mapping.  HLS doesn't
     // provide a key ID anywhere.  So although we could use the 'URI' attribute

diff --git a/test/hls/hls_parser_integration.js b/test/hls/hls_parser_integration.js
@@ -70,6 +70,13 @@ describe('HlsParser', () => {
   });
 
   it('supports AES-256 streaming', async () => {
+    let keyRequests = 0;
+    const netEngine = player.getNetworkingEngine();
+    netEngine.registerRequestFilter((type, request, context) => {
+      if (type == shaka.net.NetworkingEngine.RequestType.KEY) {
+        keyRequests++;
+      }
+    });
     await player.load('/base/test/test/assets/hls-aes-256/index.m3u8');
     await video.play();
     expect(player.isLive()).toBe(false);
@@ -83,6 +90,9 @@ describe('HlsParser', () => {
     await waiter.waitUntilPlayheadReachesOrFailOnTimeout(video, 10, 30);
 
     await player.unload();
+
+    // The stream has 6 #EXT-X-KEY but only 5 different keys.
+    expect(keyRequests).toBe(5);
   });
 
   it('supports SAMPLE-AES identity streaming', async () => {

diff --git a/test/test/assets/hls-aes-256/media.m3u8 b/test/test/assets/hls-aes-256/media.m3u8
@@ -4,7 +4,6 @@
 #EXT-X-MEDIA-SEQUENCE:1
 #EXT-X-PLAYLIST-TYPE:VOD
 #EXT-X-INDEPENDENT-SEGMENTS
-#EXT-X-KEY:METHOD=NONE
 #EXT-X-KEY:METHOD=AES-256,URI="init.key",IV=0xF9EBE119F65FCF2E5F3FDEEB4A3EB3D5
 #EXT-X-MAP:URI="init.mp4"