Merge pull request #6 from jwplayer/develop

merge to main

reader.go

@@ -532,6 +532,12 @@ func decodeLineOfMediaPlaylist(p *MediaPlaylist, wv *WV, state *decodingState, l
 				return err
 			}
 		}
+		if state.tagGap {
+			state.tagGap = false
+			if err = p.SetGap(); strict && err != nil {
+				return err
+			}
+		}
 		if state.tagProgramDateTime && p.Count() > 0 {
 			state.tagProgramDateTime = false
 			if err = p.SetProgramDateTime(state.programDateTime); strict && err != nil {
@@ -768,6 +774,9 @@ func decodeLineOfMediaPlaylist(p *MediaPlaylist, wv *WV, state *decodingState, l
 	case !state.tagDiscontinuity && strings.HasPrefix(line, "#EXT-X-DISCONTINUITY"):
 		state.tagDiscontinuity = true
 		state.listType = MEDIA
+	case !state.tagGap && strings.HasPrefix(line, "#EXT-X-GAP"):
+		state.tagGap = true
+		state.listType = MEDIA
 	case strings.HasPrefix(line, "#EXT-X-I-FRAMES-ONLY"):
 		state.listType = MEDIA
 		p.Iframe = true

reader_test.go

@@ -897,6 +897,30 @@ func TestDecodeMediaPlaylistWithCustomTags(t *testing.T) {
 	}
 }
 
+func TestDecodeMediaPlaylistWithGap(t *testing.T) {
+	f, err := os.Open("sample-playlists/media-playlist-with-gap.m3u8")
+	if err != nil {
+		t.Fatal(err)
+	}
+	p, listType, err := DecodeFrom(bufio.NewReader(f), true)
+	if err != nil {
+		t.Fatal(err)
+	}
+	pp := p.(*MediaPlaylist)
+	CheckType(t, pp)
+	if listType != MEDIA {
+		t.Error("Sample not recognized as media playlist.")
+	}
+	var seqId, idx uint
+	for seqId, idx = 0, 0; idx < pp.Count(); seqId, idx = seqId+1, idx+1 {
+		if pp.Segments[idx].Duration == 0 {
+			if !pp.Segments[idx].Gap {
+				t.Error("Expected Gap set to true on segment with duration 0.")
+			}
+		}
+	}
+}
+
 /***************************
  *  Code parsing examples  *
  ***************************/

sample-playlists/media-playlist-with-gap.m3u8

@@ -0,0 +1,18 @@
+#EXTM3U
+#EXT-X-TARGETDURATION:10
+#EXT-X-VERSION:4
+#EXT-X-MEDIA-SEQUENCE:0
+#EXTINF:10.0,
+1.ts
+#EXTINF:8.0,
+2.ts
+#EXT-X-GAP
+#EXTINF:0.0, no desc
+3.ts
+#EXT-X-DISCONTINUITY
+#EXTINF:10.0,
+4.ts
+#EXTINF:10.0,
+5.ts
+#EXTINF:10.0,
+6.ts

structure.go

@@ -214,6 +214,7 @@ type MediaSegment struct {
 	Key             *Key         // EXT-X-KEY displayed before the segment and means changing of encryption key (in theory each segment may have own key)
 	Map             *Map         // EXT-X-MAP displayed before the segment
 	Discontinuity   bool         // EXT-X-DISCONTINUITY indicates an encoding discontinuity between the media segment that follows it and the one that preceded it (i.e. file format, number and type of tracks, encoding parameters, encoding sequence, timestamp sequence)
+	Gap             bool         // EXT-X-GAP indicates that the segment URI to which it applies does not contain media data and SHOULD NOT be loaded by clients
 	DateRange       []*DateRange // EXT-X-DATERANGE tags
 	SCTE            *SCTE        // SCTE-35 used for Ad signaling in HLS
 	ProgramDateTime time.Time    // EXT-X-PROGRAM-DATE-TIME tag associates the first sample of a media segment with an absolute date and/or time
@@ -335,6 +336,7 @@ type decodingState struct {
 	tagSCTE35          bool
 	tagRange           bool
 	tagDiscontinuity   bool
+	tagGap             bool
 	tagProgramDateTime bool
 	tagKey             bool
 	tagMap             bool

writer.go

@@ -710,6 +710,9 @@ func (p *MediaPlaylist) Encode() *bytes.Buffer {
 		if seg.Discontinuity {
 			p.buf.WriteString("#EXT-X-DISCONTINUITY\n")
 		}
+		if seg.Gap {
+			p.buf.WriteString("#EXT-X-GAP\n")
+		}
 		// ignore segment Map if default playlist Map is present
 		if p.Map == nil && seg.Map != nil {
 			p.buf.WriteString("#EXT-X-MAP:")
@@ -932,6 +935,17 @@ func (p *MediaPlaylist) SetDiscontinuity() error {
 	return nil
 }
 
+// SetGap sets gap flag for the current media
+// segment. EXT-X-GAP indicates that the segment URI to which it applies
+// does not contain media data and SHOULD NOT be loaded by clients/
+func (p *MediaPlaylist) SetGap() error {
+	if p.count == 0 {
+		return errors.New("playlist is empty")
+	}
+	p.Segments[p.last()].Gap = true
+	return nil
+}
+
 // SetProgramDateTime sets program date and time for the current media
 // segment. EXT-X-PROGRAM-DATE-TIME tag associates the first sample of
 // a media segment with an absolute date and/or time. It applies only

writer_test.go

@@ -1013,6 +1013,40 @@ func TestEncodeMediaPlaylistDateRangeTags(t *testing.T) {
 	}
 }
 
+// Create new media playlist
+// Add three segments to media playlist
+// Set gap tag for the 2nd segment.
+func TestGapForMediaPlaylist(t *testing.T) {
+	var e error
+	p, e := NewMediaPlaylist(3, 4)
+	if e != nil {
+		t.Fatalf("Create media playlist failed: %s", e)
+	}
+	p.Close()
+	if e = p.Append("test01.ts", 5.0, ""); e != nil {
+		t.Errorf("Add 1st segment to a media playlist failed: %s", e)
+	}
+	if e = p.Append("test02.ts", 0.0, ""); e != nil {
+		t.Errorf("Add 2nd segment to a media playlist failed: %s", e)
+	}
+	if e = p.SetGap(); e != nil {
+		t.Error("Can't set gap tag")
+	}
+	if e = p.Append("test03.ts", 6.0, ""); e != nil {
+		t.Errorf("Add 3nd segment to a media playlist failed: %s", e)
+	}
+	if e = p.SetDiscontinuity(); e != nil {
+		t.Error("Can't set discontinuity tag")
+	}
+	encoded := p.Encode().String()
+	expectedStrings := []string{"#EXT-X-GAP"}
+	for _, expected := range expectedStrings {
+		if !strings.Contains(encoded, expected) {
+			t.Fatalf("Media playlist does not contain tag: %s\nMedia Playlist:\n%v", expected, encoded)
+		}
+	}
+}
+
 /******************************
  *  Code generation examples  *
  ******************************/