[Release] Merge develop into main (#16)

* [SSAI-500] Allow Segment Insertion into MediaPlaylist (#11) * Allow Segment Insertion into MediaPlaylist * [SSAI-702] Support EXT-X-SESSION-DATA (#15) * [SSAI-702] Support EXT-X-SESSION-DATA * add comment * SessionData struct uses pointer instead * enforce spec on strict read + test * spec compliant write * remove comments --------- Co-authored-by: Patrick Su <[email protected]>
jwplayer · Jan 24, 2025 · 72380e0 · 72380e0
1 parent 054b353
commit 72380e0
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Showing 8 changed files with 238 additions and 16 deletions.
diff --git a/reader.go b/reader.go
@@ -195,7 +195,7 @@ func decode(buf *bytes.Buffer, strict bool, customDecoders []CustomDecoder) (Pla
 	master = NewMasterPlaylist()
 	media, err = NewMediaPlaylist(8, 1024) // Winsize for VoD will become 0, capacity auto extends
 	if err != nil {
-		return nil, 0, fmt.Errorf("Create media playlist failed: %s", err)
+		return nil, 0, fmt.Errorf("create media playlist failed: %s", err)
 	}
 
 	// If we have custom tags to parse
@@ -248,7 +248,7 @@ func decode(buf *bytes.Buffer, strict bool, customDecoders []CustomDecoder) (Pla
 		}
 		return media, MEDIA, nil
 	}
-	return nil, state.listType, errors.New("Can't detect playlist type")
+	return nil, state.listType, errors.New("can't detect playlist type")
 }
 
 // DecodeAttributeList turns an attribute list into a key, value map. You should trim
@@ -290,6 +290,37 @@ func decodeLineOfMasterPlaylist(p *MasterPlaylist, state *decodingState, line st
 	switch {
 	case line == "#EXTM3U": // start tag first
 		state.m3u = true
+	case strings.HasPrefix(line, "#EXT-X-SESSION-DATA:"): // session data tag
+		state.listType = MASTER
+		sessionData := new(SessionData)
+		for k, v := range decodeParamsLine(line[20:]) {
+			switch k {
+			case "DATA-ID":
+				sessionData.DataID = v
+			case "VALUE":
+				sessionData.Value = v
+			case "URI":
+				sessionData.URI = v
+			case "LANGUAGE":
+				sessionData.Language = v
+			}
+		}
+		// EXT-X-SESSION-DATA tag MUST contain either a VALUE or URI attribute, but not both.
+		if (sessionData.Value == "" && sessionData.URI == "") || (sessionData.Value != "" && sessionData.URI != "") {
+			if strict {
+				return errors.New("either VALUE or URI must be present, but not both")
+			}
+		}
+		// A Playlist MUST NOT contain more than one EXT-X-SESSION-DATA tag with the
+		// same DATA-ID attribute and the same LANGUAGE attribute.
+		for _, sd := range p.SessionData {
+			if sd.DataID == sessionData.DataID && sd.Language == sessionData.Language {
+				if strict {
+					return errors.New("duplicate EXT-X-SESSION-DATA tag with the same DATA-ID and LANGUAGE")
+				}
+			}
+		}
+		p.SessionData = append(p.SessionData, sessionData)
 	case strings.HasPrefix(line, "#EXT-X-VERSION:"): // version tag
 		state.listType = MASTER
 		_, err = fmt.Sscanf(line, "#EXT-X-VERSION:%d", &p.ver)
@@ -443,8 +474,6 @@ func decodeLineOfMasterPlaylist(p *MasterPlaylist, state *decodingState, line st
 				state.variant.HDCPLevel = v
 			}
 		}
-	case strings.HasPrefix(line, "#"):
-		// comments are ignored
 	}
 	return err
 }
@@ -489,7 +518,7 @@ func decodeLineOfMediaPlaylist(p *MediaPlaylist, wv *WV, state *decodingState, l
 		duration := line[8:sepIndex]
 		if len(duration) > 0 {
 			if state.duration, err = strconv.ParseFloat(duration, 64); strict && err != nil {
-				return fmt.Errorf("Duration parsing error: %s", err)
+				return fmt.Errorf("duration parsing error: %s", err)
 			}
 		}
 		if len(line) > sepIndex {
@@ -626,7 +655,7 @@ func decodeLineOfMediaPlaylist(p *MediaPlaylist, wv *WV, state *decodingState, l
 			case "TIME-OFFSET":
 				st, err := strconv.ParseFloat(v, 64)
 				if err != nil {
-					return fmt.Errorf("Invalid TIME-OFFSET: %s: %v", v, err)
+					return fmt.Errorf("invalid TIME-OFFSET: %s: %v", v, err)
 				}
 				p.StartTime = st
 			case "PRECISE":
@@ -660,7 +689,7 @@ func decodeLineOfMediaPlaylist(p *MediaPlaylist, wv *WV, state *decodingState, l
 				state.xmap.URI = v
 			case "BYTERANGE":
 				if _, err = fmt.Sscanf(v, "%d@%d", &state.xmap.Limit, &state.xmap.Offset); strict && err != nil {
-					return fmt.Errorf("Byterange sub-range length value parsing error: %s", err)
+					return fmt.Errorf("byterange sub-range length value parsing error: %s", err)
 				}
 			}
 		}
@@ -727,11 +756,11 @@ func decodeLineOfMediaPlaylist(p *MediaPlaylist, wv *WV, state *decodingState, l
 		state.offset = 0
 		params := strings.SplitN(line[17:], "@", 2)
 		if state.limit, err = strconv.ParseInt(params[0], 10, 64); strict && err != nil {
-			return fmt.Errorf("Byterange sub-range length value parsing error: %s", err)
+			return fmt.Errorf("byterange sub-range length value parsing error: %s", err)
 		}
 		if len(params) > 1 {
 			if state.offset, err = strconv.ParseInt(params[1], 10, 64); strict && err != nil {
-				return fmt.Errorf("Byterange sub-range offset value parsing error: %s", err)
+				return fmt.Errorf("byterange sub-range offset value parsing error: %s", err)
 			}
 		}
 	case !state.tagSCTE35 && strings.HasPrefix(line, "#EXT-SCTE35:"):
@@ -893,8 +922,6 @@ func decodeLineOfMediaPlaylist(p *MediaPlaylist, wv *WV, state *decodingState, l
 		if err == nil {
 			state.tagWV = true
 		}
-	case strings.HasPrefix(line, "#"):
-		// comments are ignored
 	}
 	return err
 }

diff --git a/reader_test.go b/reader_test.go
@@ -41,6 +41,86 @@ func TestDecodeMasterPlaylist(t *testing.T) {
 	// fmt.Println(p.Encode().String())
 }
 
+func TestDecodeMasterPlaylist_WithSessionData(t *testing.T) {
+	f, err := os.Open("sample-playlists/master-with-session-data.m3u8")
+	if err != nil {
+		t.Fatal(err)
+	}
+	p := NewMasterPlaylist()
+	err = p.DecodeFrom(bufio.NewReader(f), false)
+	if err != nil {
+		t.Fatal(err)
+	}
+	// check parsed values
+	if p.ver != 3 {
+		t.Errorf("Version of parsed playlist = %d (must = 3)", p.ver)
+	}
+	if len(p.Variants) != 5 {
+		t.Error("Not all variants in master playlist parsed.")
+	}
+
+	if len(p.SessionData) < 1 {
+		t.Error("Session data has not been parsed.")
+	}
+
+	// check specific session data values
+	expectedSessionData := []SessionData{
+		{
+			DataID:   "com.example.movie.title",
+			Value:    "Example Movie",
+			Language: "en",
+		},
+		{
+			DataID: "com.example.movie.description",
+			URI:    "http://example.com/description.json",
+		},
+	}
+
+	for i, expected := range expectedSessionData {
+		if i >= len(p.SessionData) {
+			t.Errorf("Missing session data entry: %+v", expected)
+			continue
+		}
+		actual := p.SessionData[i]
+		if actual.DataID != expected.DataID {
+			t.Errorf("SessionData[%d].DataID = %s, want %s", i, actual.DataID, expected.DataID)
+		}
+		if actual.Value != expected.Value {
+			t.Errorf("SessionData[%d].Value = %s, want %s", i, actual.Value, expected.Value)
+		}
+		if actual.URI != expected.URI {
+			t.Errorf("SessionData[%d].URI = %s, want %s", i, actual.URI, expected.URI)
+		}
+		if actual.Language != expected.Language {
+			t.Errorf("SessionData[%d].Language = %s, want %s", i, actual.Language, expected.Language)
+		}
+	}
+}
+
+func TestDecodeMasterPlaylist_WithBothValueAndURI(t *testing.T) {
+	f, err := os.Open("sample-playlists/master-with-session-data-with-uri-and-value.m3u8")
+	if err != nil {
+		t.Fatal(err)
+	}
+	p := NewMasterPlaylist()
+	err = p.DecodeFrom(bufio.NewReader(f), true)
+	if err == nil {
+		t.Error("Expected error when strict mode is enabled.")
+	}
+}
+
+func TestDecodeMasterPlaylist_WithDuplicateDataIDAndLanguage(t *testing.T) {
+	f, err := os.Open("sample-playlists/master-with-session-data-with-duplicate-data-id-and-language.m3u8")
+	if err != nil {
+		t.Fatal(err)
+	}
+	p := NewMasterPlaylist()
+	err = p.DecodeFrom(bufio.NewReader(f), true)
+	if err == nil {
+		t.Error("Expected error when strict mode is enabled.")
+	}
+}
+
 func TestDecodeMasterPlaylistWithMultipleCodecs(t *testing.T) {
 	f, err := os.Open("sample-playlists/master-with-multiple-codecs.m3u8")
 	if err != nil {

diff --git a/sample-playlists/master-with-session-data-with-duplicate-data-id-and-language.m3u8 b/sample-playlists/master-with-session-data-with-duplicate-data-id-and-language.m3u8
@@ -0,0 +1,14 @@
+#EXTM3U
+#EXT-X-VERSION:3
+#EXT-X-SESSION-DATA:DATA-ID="com.example.movie.title",VALUE="Example Movie",LANGUAGE="en"
+#EXT-X-SESSION-DATA:DATA-ID="com.example.movie.title",VALUE="Example Movie",LANGUAGE="en"
+#EXT-X-STREAM-INF:PROGRAM-ID=1,BANDWIDTH=300000
+chunklist-b300000.m3u8
+#EXT-X-STREAM-INF:PROGRAM-ID=1,BANDWIDTH=600000
+chunklist-b600000.m3u8
+#EXT-X-STREAM-INF:PROGRAM-ID=1,BANDWIDTH=850000
+chunklist-b850000.m3u8
+#EXT-X-STREAM-INF:PROGRAM-ID=1,BANDWIDTH=1000000
+chunklist-b1000000.m3u8
+#EXT-X-STREAM-INF:PROGRAM-ID=1,BANDWIDTH=1500000
+chunklist-b1500000.m3u8
diff --git a/sample-playlists/master-with-session-data-with-uri-and-value.m3u8 b/sample-playlists/master-with-session-data-with-uri-and-value.m3u8
@@ -0,0 +1,13 @@
+#EXTM3U
+#EXT-X-VERSION:3
+#EXT-X-SESSION-DATA:DATA-ID="com.example.movie.title",VALUE="Example Movie",LANGUAGE="en",URI="http://example.com/description.json"
+#EXT-X-STREAM-INF:PROGRAM-ID=1,BANDWIDTH=300000
+chunklist-b300000.m3u8
+#EXT-X-STREAM-INF:PROGRAM-ID=1,BANDWIDTH=600000
+chunklist-b600000.m3u8
+#EXT-X-STREAM-INF:PROGRAM-ID=1,BANDWIDTH=850000
+chunklist-b850000.m3u8
+#EXT-X-STREAM-INF:PROGRAM-ID=1,BANDWIDTH=1000000
+chunklist-b1000000.m3u8
+#EXT-X-STREAM-INF:PROGRAM-ID=1,BANDWIDTH=1500000
+chunklist-b1500000.m3u8
diff --git a/sample-playlists/master-with-session-data.m3u8 b/sample-playlists/master-with-session-data.m3u8
@@ -0,0 +1,14 @@
+#EXTM3U
+#EXT-X-VERSION:3
+#EXT-X-SESSION-DATA:DATA-ID="com.example.movie.title",VALUE="Example Movie",LANGUAGE="en"
+#EXT-X-SESSION-DATA:DATA-ID="com.example.movie.description",URI="http://example.com/description.json"
+#EXT-X-STREAM-INF:PROGRAM-ID=1,BANDWIDTH=300000
+chunklist-b300000.m3u8
+#EXT-X-STREAM-INF:PROGRAM-ID=1,BANDWIDTH=600000
+chunklist-b600000.m3u8
+#EXT-X-STREAM-INF:PROGRAM-ID=1,BANDWIDTH=850000
+chunklist-b850000.m3u8
+#EXT-X-STREAM-INF:PROGRAM-ID=1,BANDWIDTH=1000000
+chunklist-b1000000.m3u8
+#EXT-X-STREAM-INF:PROGRAM-ID=1,BANDWIDTH=1500000
+chunklist-b1500000.m3u8
diff --git a/structure.go b/structure.go
@@ -147,6 +147,7 @@ type MediaPlaylist struct {
 //	http://example.com/audio-only.m3u8
 type MasterPlaylist struct {
 	Variants            []*Variant
+	SessionData         []*SessionData
 	Args                string // optional arguments placed after URI (URI?Args)
 	CypherVersion       string // non-standard tag for Widevine (see also WV struct)
 	buf                 bytes.Buffer
@@ -165,6 +166,14 @@ type Variant struct {
 	VariantParams
 }
 
+// SessionData structure represents EXT-X-SESSION-DATA tag in the master playlist.
+type SessionData struct {
+	DataID   string
+	Value    string
+	URI      string
+	Language string
+}
+
 // VariantParams structure represents additional parameters for a
 // variant used in EXT-X-STREAM-INF and EXT-X-I-FRAME-STREAM-INF
 type VariantParams struct {

diff --git a/writer.go b/writer.go
@@ -96,6 +96,43 @@ func (p *MasterPlaylist) Encode() *bytes.Buffer {
 		}
 	}
 
+	var languageWritten = make(map[string]bool)
+	if p.SessionData != nil {
+		for _, sessionData := range p.SessionData {
+			// make sure that the same data id and language is not written twice
+			if sessionData.Language != "" {
+				languageWrittenKey := strings.ToLower(sessionData.DataID) + "-" + strings.ToLower(sessionData.Language)
+				if languageWritten[languageWrittenKey] {
+					continue
+				}
+				languageWritten[languageWrittenKey] = true
+			}
+
+			p.buf.WriteString("#EXT-X-SESSION-DATA:")
+			p.buf.WriteString("DATA-ID=\"")
+			p.buf.WriteString(sessionData.DataID)
+			p.buf.WriteRune('"')
+			if sessionData.Value != "" {
+				p.buf.WriteString(",VALUE=\"")
+				p.buf.WriteString(sessionData.Value)
+				p.buf.WriteRune('"')
+			}
+			// Each EXT-X-SESSION-DATA tag MUST contain either a VALUE or URI attribute, but not both.
+			// In case both are present, default to writing only the VALUE attribute.
+			if sessionData.URI != "" && sessionData.Value == "" {
+				p.buf.WriteString(",URI=\"")
+				p.buf.WriteString(sessionData.URI)
+				p.buf.WriteRune('"')
+			}
+			if sessionData.Language != "" {
+				p.buf.WriteString(",LANGUAGE=\"")
+				p.buf.WriteString(sessionData.Language)
+				p.buf.WriteRune('"')
+			}
+			p.buf.WriteRune('\n')
+		}
+	}
+
 	var altsWritten = make(map[string]bool)
 
 	for _, pl := range p.Variants {

diff --git a/writer_test.go b/writer_test.go
@@ -13,7 +13,6 @@ import (
 	"bufio"
 	"bytes"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"reflect"
 	"strings"
@@ -587,7 +586,7 @@ func TestClosedMediaPlaylist(t *testing.T) {
 // Create new media playlist as sliding playlist.
 func TestLargeMediaPlaylistWithParallel(t *testing.T) {
 	testCount := 10
-	expect, err := ioutil.ReadFile("sample-playlists/media-playlist-large.m3u8")
+	expect, err := os.ReadFile("sample-playlists/media-playlist-large.m3u8")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -609,7 +608,7 @@ func TestLargeMediaPlaylistWithParallel(t *testing.T) {
 			}
 
 			actual := p.Encode().Bytes() // disregard output
-			if bytes.Compare(expect, actual) != 0 {
+			if !bytes.Equal(expect, actual) {
 				t.Fatal("not matched")
 			}
 		}()
@@ -802,6 +801,35 @@ func TestNewMasterPlaylistWithAlternatives(t *testing.T) {
 	}
 }
 
+func TestNewMasterPlaylistWithSessionData(t *testing.T) {
+	m := NewMasterPlaylist()
+	m.SessionData = []*SessionData{
+		{
+			DataID:   "com.example.movie.title",
+			Value:    "Example Movie",
+			Language: "en",
+		},
+		{
+			DataID: "com.example.movie.description",
+			URI:    "http://example.com/description.json",
+		},
+	}
+
+	var buf bytes.Buffer
+	m.buf = buf
+
+	output := m.Encode().String()
+	expected := `#EXTM3U
+#EXT-X-VERSION:3
+#EXT-X-SESSION-DATA:DATA-ID="com.example.movie.title",VALUE="Example Movie",LANGUAGE="en"
+#EXT-X-SESSION-DATA:DATA-ID="com.example.movie.description",URI="http://example.com/description.json"
+`
+
+	if output != expected {
+		t.Errorf("expected:\n%s\ngot:\n%s", expected, output)
+	}
+}
+
 // Create new master playlist supporting CLOSED-CAPTIONS=NONE
 func TestNewMasterPlaylistWithClosedCaptionEqNone(t *testing.T) {
 	m := NewMasterPlaylist()
@@ -819,7 +847,7 @@ func TestNewMasterPlaylistWithClosedCaptionEqNone(t *testing.T) {
 	if err != nil {
 		t.Fatalf("Create media playlist failed: %s", err)
 	}
-	m.Append(fmt.Sprintf("eng_rendition_rendition.m3u8"), p, *vp)
+	m.Append("eng_rendition_rendition.m3u8", p, *vp)
 
 	expected := "CLOSED-CAPTIONS=NONE"
 	if !strings.Contains(m.String(), expected) {
@@ -828,7 +856,7 @@ func TestNewMasterPlaylistWithClosedCaptionEqNone(t *testing.T) {
 	// quotes need to be include if not eq NONE
 	vp.Captions = "CC1"
 	m2 := NewMasterPlaylist()
-	m2.Append(fmt.Sprintf("eng_rendition_rendition.m3u8"), p, *vp)
+	m2.Append("eng_rendition_rendition.m3u8", p, *vp)
 	expected = `CLOSED-CAPTIONS="CC1"`
 	if !strings.Contains(m2.String(), expected) {
 		t.Fatalf("Master playlist did not contain: %s\nMaster Playlist:\n%v", expected, m2.String())