support optional URI in EXT-X-MEDIA tag (#104)

* URI is OPTIONAL in EXT-X-MEDIA tag * make URI mandatory in case of SUBTITLES * adapt client in order to work with renditions without URLs --------- Co-authored-by: aler9 <46489434+aler9@users.noreply.github.com>
bluenviron · Nov 22, 2023 · 30c4379 · 30c4379
1 parent 6cb7c43
commit 30c4379
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Showing 3 changed files with 47 additions and 31 deletions.
diff --git a/client_downloader_primary.go b/client_downloader_primary.go
@@ -209,27 +209,29 @@ func (d *clientDownloaderPrimary) run(ctx context.Context) error {
  return fmt.Errorf("audio playlist with id \"%s\" not found", leadingPlaylist.Audio)
  }
 
- u, err := clientAbsoluteURL(d.primaryPlaylistURL, audioPlaylist.URI)
- if err != nil {
- return err
+ if audioPlaylist.URI != "" {
+ u, err := clientAbsoluteURL(d.primaryPlaylistURL, audioPlaylist.URI)
+ if err != nil {
+ return err
+ }
+
+ ds := newClientDownloaderStream(
+ false,
+ d.httpClient,
+ d.onDownloadStreamPlaylist,
+ d.onDownloadSegment,
+ d.onDecodeError,
+ u,
+ nil,
+ d.rp,
+ d.onStreamTracks,
+ d.onSetLeadingTimeSync,
+ d.onGetLeadingTimeSync,
+ d.onData,
+ )
+ d.rp.add(ds)
+ streamCount++
  }
-
- ds := newClientDownloaderStream(
- false,
- d.httpClient,
- d.onDownloadStreamPlaylist,
- d.onDownloadSegment,
- d.onDecodeError,
- u,
- nil,
- d.rp,
- d.onStreamTracks,
- d.onSetLeadingTimeSync,
- d.onGetLeadingTimeSync,
- d.onData,
- )
- d.rp.add(ds)
- streamCount++
  }
 
  default:

diff --git a/pkg/playlist/multivariant_rendition.go b/pkg/playlist/multivariant_rendition.go
@@ -111,22 +111,32 @@ func (t *MultivariantRendition) unmarshal(v string) error {
  return fmt.Errorf("GROUP-ID missing")
  }
 
- if t.Type != MultivariantRenditionTypeClosedCaptions {
- if t.URI == "" {
- return fmt.Errorf("missing URI")
- }
-
- if t.InstreamID != "" {
- return fmt.Errorf("INSTREAM-ID is forbidden with type %s", t.Type)
- }
- } else {
+ // If the TYPE is CLOSED-CAPTIONS, the URI
+ // attribute MUST NOT be present.
+ // The URI attribute of the EXT-X-MEDIA tag is REQUIRED if the media
+ // type is SUBTITLES, but OPTIONAL if the media type is VIDEO or AUDIO.
+ switch t.Type {
+ case MultivariantRenditionTypeClosedCaptions:
  if t.URI != "" {
  return fmt.Errorf("URI is forbidden for type CLOSED-CAPTIONS")
  }
 
+ case MultivariantRenditionTypeSubtitles:
+ if t.URI == "" {
+ return fmt.Errorf("URI is required for type SUBTITLES")
+ }
+
+ default:
+ }
+
+ // This attribute is REQUIRED if the TYPE attribute is CLOSED-CAPTIONS
+ // For all other TYPE values, the INSTREAM-ID MUST NOT be specified.
+ if t.Type == MultivariantRenditionTypeClosedCaptions {
  if t.InstreamID == "" {
  return fmt.Errorf("missing INSTREAM-ID")
  }
+ } else if t.InstreamID != "" {
+ return fmt.Errorf("INSTREAM-ID is forbidden with type %s", t.Type)
  }
 
  return nil
@@ -164,7 +174,11 @@ func (t MultivariantRendition) marshal() string {
  ret += ",CHANNELS=\"" + t.Channels + "\""
  }
 
- ret += ",URI=\"" + t.URI + "\"\n"
+ if t.URI != "" {
+ ret += ",URI=\"" + t.URI + "\""
+ }
+
+ ret += "\n"
 
  return ret
 }
diff --git a/pkg/playlist/multivariant_test.go b/pkg/playlist/multivariant_test.go
@@ -256,7 +256,7 @@ v2/prog_index.m3u8
 #EXT-X-MEDIA:TYPE="AUDIO",GROUP-ID="aud1",LANGUAGE="en",NAME="English",DEFAULT=YES,AUTOSELECT=YES,CHANNELS="2",URI="a1/prog_index.m3u8"
 #EXT-X-MEDIA:TYPE="AUDIO",GROUP-ID="aud2",LANGUAGE="en",NAME="English",DEFAULT=YES,AUTOSELECT=YES,CHANNELS="6",URI="a2/prog_index.m3u8"
 #EXT-X-MEDIA:TYPE="AUDIO",GROUP-ID="aud3",LANGUAGE="en",NAME="English",DEFAULT=YES,AUTOSELECT=YES,CHANNELS="6",URI="a3/prog_index.m3u8"
-#EXT-X-MEDIA:TYPE="CLOSED-CAPTIONS",GROUP-ID="cc1",LANGUAGE="en",NAME="English",DEFAULT=YES,AUTOSELECT=YES,URI=""
+#EXT-X-MEDIA:TYPE="CLOSED-CAPTIONS",GROUP-ID="cc1",LANGUAGE="en",NAME="English",DEFAULT=YES,AUTOSELECT=YES
 #EXT-X-MEDIA:TYPE="SUBTITLES",GROUP-ID="sub1",LANGUAGE="en",NAME="English",DEFAULT=YES,AUTOSELECT=YES,FORCED=NO,URI="s1/en/prog_index.m3u8"
 `,
  Multivariant{