Pass HTTP DataSource's response headers to HlsExtractorFactory

Issue:#2025

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=200212344

RELEASENOTES.md

@@ -15,6 +15,7 @@
   bandwidth estimates in the future. Always null at the moment.
 * HLS:
   * Allow injection of custom playlist trackers.
+  * Pass HTTP response headers to `HlsExtractorFactory.createExtractor`.
 * DRM:
   * Allow DrmInitData to carry a license server URL
     ([#3393](https://github.com/google/ExoPlayer/issues/3393)).

library/hls/src/main/java/com/google/android/exoplayer2/source/hls/DefaultHlsExtractorFactory.java

@@ -31,6 +31,7 @@ import com.google.android.exoplayer2.util.MimeTypes;
 import com.google.android.exoplayer2.util.TimestampAdjuster;
 import java.util.Collections;
 import java.util.List;
+import java.util.Map;
 
 /**
  * Default {@link HlsExtractorFactory} implementation.
@@ -48,9 +49,14 @@ public final class DefaultHlsExtractorFactory implements HlsExtractorFactory {
   public static final String WEBVTT_FILE_EXTENSION = ".webvtt";
 
   @Override
-  public Pair<Extractor, Boolean> createExtractor(Extractor previousExtractor, Uri uri,
-      Format format, List<Format> muxedCaptionFormats, DrmInitData drmInitData,
-      TimestampAdjuster timestampAdjuster) {
+  public Pair<Extractor, Boolean> createExtractor(
+      Extractor previousExtractor,
+      Uri uri,
+      Format format,
+      List<Format> muxedCaptionFormats,
+      DrmInitData drmInitData,
+      TimestampAdjuster timestampAdjuster,
+      Map<String, List<String>> responseHeaders) {
     String lastPathSegment = uri.getLastPathSegment();
     if (lastPathSegment == null) {
       lastPathSegment = "";

library/hls/src/main/java/com/google/android/exoplayer2/source/hls/HlsExtractorFactory.java

@@ -22,6 +22,7 @@ import com.google.android.exoplayer2.drm.DrmInitData;
 import com.google.android.exoplayer2.extractor.Extractor;
 import com.google.android.exoplayer2.util.TimestampAdjuster;
 import java.util.List;
+import java.util.Map;
 
 /**
  * Factory for HLS media chunk extractors.
@@ -42,12 +43,18 @@ public interface HlsExtractorFactory {
    *     information is available in the master playlist.
    * @param drmInitData {@link DrmInitData} associated with the chunk.
    * @param timestampAdjuster Adjuster corresponding to the provided discontinuity sequence number.
+   * @param responseHeaders The HTTP response headers associated with the media segment or
+   *     initialization section to extract.
    * @return A pair containing the {@link Extractor} and a boolean that indicates whether it is a
    *     packed audio extractor. The first element may be {@code previousExtractor} if the factory
    *     has determined it can be re-used.
    */
-  Pair<Extractor, Boolean> createExtractor(Extractor previousExtractor, Uri uri, Format format,
-      List<Format> muxedCaptionFormats, DrmInitData drmInitData,
-      TimestampAdjuster timestampAdjuster);
-
+  Pair<Extractor, Boolean> createExtractor(
+      Extractor previousExtractor,
+      Uri uri,
+      Format format,
+      List<Format> muxedCaptionFormats,
+      DrmInitData drmInitData,
+      TimestampAdjuster timestampAdjuster,
+      Map<String, List<String>> responseHeaders);
 }

library/hls/src/main/java/com/google/android/exoplayer2/source/hls/HlsMediaChunk.java

@@ -69,12 +69,15 @@ import java.util.concurrent.atomic.AtomicInteger;
   private final boolean hasGapTag;
   private final TimestampAdjuster timestampAdjuster;
   private final boolean shouldSpliceIn;
-  private final Extractor extractor;
-  private final boolean isPackedAudioExtractor;
-  private final boolean reusingExtractor;
-  private final Id3Decoder id3Decoder;
-  private final ParsableByteArray id3Data;
+  private final HlsExtractorFactory extractorFactory;
+  private final List<Format> muxedCaptionFormats;
+  private final DrmInitData drmInitData;
+  private final Extractor previousExtractor;
 
+  private Extractor extractor;
+  private boolean isPackedAudioExtractor;
+  private Id3Decoder id3Decoder;
+  private ParsableByteArray id3Data;
   private HlsSampleStreamWrapper output;
   private int initSegmentBytesLoaded;
   private int bytesLoaded;
@@ -145,32 +148,20 @@ import java.util.concurrent.atomic.AtomicInteger;
     // Note: this.dataSource and dataSource may be different.
     this.isEncrypted = this.dataSource instanceof Aes128DataSource;
     this.hasGapTag = hasGapTag;
+    this.extractorFactory = extractorFactory;
+    this.muxedCaptionFormats = muxedCaptionFormats;
+    this.drmInitData = drmInitData;
     Extractor previousExtractor = null;
     if (previousChunk != null) {
+      id3Decoder = previousChunk.id3Decoder;
+      id3Data = previousChunk.id3Data;
       shouldSpliceIn = previousChunk.hlsUrl != hlsUrl;
       previousExtractor = previousChunk.discontinuitySequenceNumber != discontinuitySequenceNumber
           || shouldSpliceIn ? null : previousChunk.extractor;
     } else {
       shouldSpliceIn = false;
     }
-    Pair<Extractor, Boolean> extractorData = extractorFactory.createExtractor(previousExtractor,
-        dataSpec.uri, trackFormat, muxedCaptionFormats, drmInitData, timestampAdjuster);
-    extractor = extractorData.first;
-    isPackedAudioExtractor = extractorData.second;
-    reusingExtractor = extractor == previousExtractor;
-    initLoadCompleted = reusingExtractor && initDataSpec != null;
-    if (isPackedAudioExtractor) {
-      if (previousChunk != null && previousChunk.id3Data != null) {
-        id3Decoder = previousChunk.id3Decoder;
-        id3Data = previousChunk.id3Data;
-      } else {
-        id3Decoder = new Id3Decoder();
-        id3Data = new ParsableByteArray(Id3Decoder.ID3_HEADER_LENGTH);
-      }
-    } else {
-      id3Decoder = null;
-      id3Data = null;
-    }
+    this.previousExtractor = previousExtractor;
     initDataSource = dataSource;
     uid = uidSource.getAndIncrement();
   }
@@ -183,10 +174,6 @@ import java.util.concurrent.atomic.AtomicInteger;
    */
   public void init(HlsSampleStreamWrapper output) {
     this.output = output;
-    output.init(uid, shouldSpliceIn, reusingExtractor);
-    if (!reusingExtractor) {
-      extractor.init(output);
-    }
   }
 
   @Override
@@ -217,7 +204,7 @@ import java.util.concurrent.atomic.AtomicInteger;
     }
   }
 
-  // Internal loading methods.
+  // Internal methods.
 
   private void maybeLoadInitData() throws IOException, InterruptedException {
     if (initLoadCompleted || initDataSpec == null) {
@@ -226,8 +213,7 @@ import java.util.concurrent.atomic.AtomicInteger;
     }
     DataSpec initSegmentDataSpec = initDataSpec.subrange(initSegmentBytesLoaded);
     try {
-      ExtractorInput input = new DefaultExtractorInput(initDataSource,
-          initSegmentDataSpec.absoluteStreamPosition, initDataSource.open(initSegmentDataSpec));
+      DefaultExtractorInput input = prepareExtraction(initDataSource, initSegmentDataSpec);
       try {
         int result = Extractor.RESULT_CONTINUE;
         while (result == Extractor.RESULT_CONTINUE && !loadCanceled) {
@@ -263,8 +249,7 @@ import java.util.concurrent.atomic.AtomicInteger;
       timestampAdjuster.setFirstSampleTimestampUs(startTimeUs);
     }
     try {
-      ExtractorInput input = new DefaultExtractorInput(dataSource,
-          loadDataSpec.absoluteStreamPosition, dataSource.open(loadDataSpec));
+      ExtractorInput input = prepareExtraction(dataSource, loadDataSpec);
       if (isPackedAudioExtractor && !id3TimestampPeeked) {
         long id3Timestamp = peekId3PrivTimestamp(input);
         id3TimestampPeeked = true;
@@ -287,6 +272,37 @@ import java.util.concurrent.atomic.AtomicInteger;
     }
   }
 
+  private DefaultExtractorInput prepareExtraction(DataSource dataSource, DataSpec dataSpec)
+      throws IOException {
+    long bytesToRead = dataSource.open(dataSpec);
+
+    if (extractor == null) {
+      Pair<Extractor, Boolean> extractorData =
+          extractorFactory.createExtractor(
+              previousExtractor,
+              dataSpec.uri,
+              trackFormat,
+              muxedCaptionFormats,
+              drmInitData,
+              timestampAdjuster,
+              dataSource.getResponseHeaders());
+      extractor = extractorData.first;
+      isPackedAudioExtractor = extractorData.second;
+      boolean reusingExtractor = extractor == previousExtractor;
+      initLoadCompleted = reusingExtractor && initDataSpec != null;
+      if (isPackedAudioExtractor && id3Data == null) {
+        id3Decoder = new Id3Decoder();
+        id3Data = new ParsableByteArray(Id3Decoder.ID3_HEADER_LENGTH);
+      }
+      output.init(uid, shouldSpliceIn, reusingExtractor);
+      if (!reusingExtractor) {
+        extractor.init(output);
+      }
+    }
+
+    return new DefaultExtractorInput(dataSource, dataSpec.absoluteStreamPosition, bytesToRead);
+  }
+
   /**
    * Peek the presentation timestamp of the first sample in the chunk from an ID3 PRIV as defined
    * in the HLS spec, version 20, Section 3.4. Returns {@link C#TIME_UNSET} if the frame is not