Playlists: Use subtitle when author is missing (#4025)

Co-authored-by: Samantaz Fox <coding@samantaz.fr>

.github/workflows/ci.yml

@@ -38,11 +38,10 @@ jobs:
       matrix:
         stable: [true]
         crystal:
-          - 1.4.1
-          - 1.5.1
           - 1.6.2
           - 1.7.3
           - 1.8.2
+          - 1.9.2
         include:
           - crystal: nightly
             stable: false
@@ -53,7 +52,7 @@ jobs:
           submodules: true
 
       - name: Install Crystal
-        uses: crystal-lang/install-crystal@v1.7.0
+        uses: crystal-lang/install-crystal@v1.8.0
         with:
           crystal: ${{ matrix.crystal }}
 

.github/workflows/container-release.yml

@@ -25,9 +25,9 @@ jobs:
         uses: actions/checkout@v3
 
       - name: Install Crystal
-        uses: crystal-lang/install-crystal@v1.6.0
+        uses: crystal-lang/install-crystal@v1.8.0
         with:
-          crystal: 1.5.0
+          crystal: 1.9.2
 
       - name: Run lint
         run: |
@@ -77,4 +77,3 @@ jobs:
           tags: quay.io/invidious/invidious:${{ github.sha }}-arm64,quay.io/invidious/invidious:latest-arm64
           build-args: |
             "release=1"
-        

.github/workflows/stale.yml

@@ -14,7 +14,7 @@ jobs:
       with:
         repo-token: ${{ secrets.GITHUB_TOKEN }}
         days-before-stale: 365
-        days-before-pr-stale: 45 # PRs should be active. Anything that hasn't had activity in more than 45 days should be considered abandoned.
+        days-before-pr-stale: 90 
         days-before-close: 30
         exempt-pr-labels: blocked
         stale-issue-message: 'This issue has been automatically marked as stale and will be closed in 30 days because it has not had recent activity and is much likely outdated. If you think this issue is still relevant and applicable, you just have to post a comment and it will be unmarked.'

config/config.example.yml

@@ -161,6 +161,19 @@ https_only: false
 #force_resolve:
 
 
+##
+## Use Innertube's transcripts API instead of timedtext for closed captions
+##
+## Useful for larger instances as InnerTube is **not ratelimited**. See https://github.com/iv-org/invidious/issues/2567
+##
+## Subtitle experience may differ slightly on Invidious.
+##
+## Accepted values: true, false
+## Default: false
+##
+# use_innertube_for_captions: false
+
+
 # -----------------------------
 #  Logging
 # -----------------------------

src/invidious/config.cr

@@ -127,6 +127,9 @@ class Config
   # Pool size for HTTP requests to youtube.com and ytimg.com (each domain has a separate pool of `pool_size`)
   property pool_size : Int32 = 100
 
+  # Use Innertube's transcripts API instead of timedtext for closed captions
+  property use_innertube_for_captions : Bool = false
+
   # Saved cookies in "name1=value1; name2=value2..." format
   @[YAML::Field(converter: Preferences::StringToCookies)]
   property cookies : HTTP::Cookies = HTTP::Cookies.new

src/invidious/frontend/watch_page.cr

@@ -7,7 +7,7 @@ module Invidious::Frontend::WatchPage
     getter full_videos : Array(Hash(String, JSON::Any))
     getter video_streams : Array(Hash(String, JSON::Any))
     getter audio_streams : Array(Hash(String, JSON::Any))
-    getter captions : Array(Invidious::Videos::Caption)
+    getter captions : Array(Invidious::Videos::Captions::Metadata)
 
     def initialize(
       @full_videos,

src/invidious/playlists.cr

@@ -89,6 +89,7 @@ struct Playlist
   property views : Int64
   property updated : Time
   property thumbnail : String?
+  property subtitle : String?
 
   def to_json(offset, json : JSON::Builder, video_id : String? = nil)
     json.object do
@@ -100,6 +101,7 @@ struct Playlist
       json.field "author", self.author
       json.field "authorId", self.ucid
       json.field "authorUrl", "/channel/#{self.ucid}"
+      json.field "subtitle", self.subtitle
 
       json.field "authorThumbnails" do
         json.array do
@@ -356,6 +358,8 @@ def fetch_playlist(plid : String)
   updated = Time.utc
   video_count = 0
 
+  subtitle = extract_text(initial_data.dig?("header", "playlistHeaderRenderer", "subtitle"))
+
   playlist_info["stats"]?.try &.as_a.each do |stat|
     text = stat["runs"]?.try &.as_a.map(&.["text"].as_s).join("") || stat["simpleText"]?.try &.as_s
     next if !text
@@ -397,6 +401,7 @@ def fetch_playlist(plid : String)
     views:            views,
     updated:          updated,
     thumbnail:        thumbnail,
+    subtitle:         subtitle,
   })
 end
 

src/invidious/routes/api/v1/videos.cr

@@ -87,6 +87,13 @@ module Invidious::Routes::API::V1::Videos
       caption = caption[0]
     end
 
+    if CONFIG.use_innertube_for_captions
+      params = Invidious::Videos::Transcript.generate_param(id, caption.language_code, caption.auto_generated)
+      initial_data = YoutubeAPI.get_transcript(params)
+
+      webvtt = Invidious::Videos::Transcript.convert_transcripts_to_vtt(initial_data, caption.language_code)
+    else
+      # Timedtext API handling
       url = URI.parse("#{caption.base_url}&tlang=#{tlang}").request_target
 
       # Auto-generated captions often have cues that aren't aligned properly with the video,
@@ -153,6 +160,7 @@ module Invidious::Routes::API::V1::Videos
             .gsub(/([0-9:.]{12} --> [0-9:.]{12}).+/, "\\1")
         end
       end
+    end
 
     if title = env.params.query["title"]?
       # https://blog.fastmail.com/2011/06/24/download-non-english-filenames/

src/invidious/videos.cr

@@ -24,7 +24,7 @@ struct Video
   property updated : Time
 
   @[DB::Field(ignore: true)]
-  @captions = [] of Invidious::Videos::Caption
+  @captions = [] of Invidious::Videos::Captions::Metadata
 
   @[DB::Field(ignore: true)]
   property adaptive_fmts : Array(Hash(String, JSON::Any))?
@@ -215,9 +215,9 @@ struct Video
     keywords.includes? "YouTube Red"
   end
 
-  def captions : Array(Invidious::Videos::Caption)
+  def captions : Array(Invidious::Videos::Captions::Metadata)
     if @captions.empty? && @info.has_key?("captions")
-      @captions = Invidious::Videos::Caption.from_yt_json(info["captions"])
+      @captions = Invidious::Videos::Captions::Metadata.from_yt_json(info["captions"])
     end
 
     return @captions

src/invidious/videos/caption.cr

@@ -1,21 +1,24 @@
 require "json"
 
 module Invidious::Videos
-  struct Caption
+  module Captions
+    struct Metadata
       property name : String
       property language_code : String
       property base_url : String
 
-    def initialize(@name, @language_code, @base_url)
+      property auto_generated : Bool
+
+      def initialize(@name, @language_code, @base_url, @auto_generated)
       end
 
       # Parse the JSON structure from Youtube
-    def self.from_yt_json(container : JSON::Any) : Array(Caption)
+      def self.from_yt_json(container : JSON::Any) : Array(Captions::Metadata)
         caption_tracks = container
           .dig?("playerCaptionsTracklistRenderer", "captionTracks")
           .try &.as_a
 
-      captions_list = [] of Caption
+        captions_list = [] of Captions::Metadata
         return captions_list if caption_tracks.nil?
 
         caption_tracks.each do |caption|
@@ -25,7 +28,9 @@ module Invidious::Videos
           language_code = caption["languageCode"].to_s
           base_url = caption["baseUrl"].to_s
 
-        captions_list << Caption.new(name, language_code, base_url)
+          auto_generated = (caption["kind"]? == "asr")
+
+          captions_list << Captions::Metadata.new(name, language_code, base_url, auto_generated)
         end
 
         return captions_list
@@ -96,6 +101,7 @@ module Invidious::Videos
         end
         return result
       end
+    end
 
     # List of all caption languages available on Youtube.
     LANGUAGES = {

src/invidious/videos/transcript.cr

@@ -0,0 +1,103 @@
+module Invidious::Videos
+  # Namespace for methods primarily relating to Transcripts
+  module Transcript
+    record TranscriptLine, start_ms : Time::Span, end_ms : Time::Span, line : String
+
+    def self.generate_param(video_id : String, language_code : String, auto_generated : Bool) : String
+      kind = auto_generated ? "asr" : ""
+
+      object = {
+        "1:0:string" => video_id,
+
+        "2:base64" => {
+          "1:string" => kind,
+          "2:string" => language_code,
+          "3:string" => "",
+        },
+
+        "3:varint" => 1_i64,
+        "5:string" => "engagement-panel-searchable-transcript-search-panel",
+        "6:varint" => 1_i64,
+        "7:varint" => 1_i64,
+        "8:varint" => 1_i64,
+      }
+
+      params = object.try { |i| Protodec::Any.cast_json(i) }
+        .try { |i| Protodec::Any.from_json(i) }
+        .try { |i| Base64.urlsafe_encode(i) }
+        .try { |i| URI.encode_www_form(i) }
+
+      return params
+    end
+
+    def self.convert_transcripts_to_vtt(initial_data : Hash(String, JSON::Any), target_language : String) : String
+      # Convert into array of TranscriptLine
+      lines = self.parse(initial_data)
+
+      # Taken from Invidious::Videos::Captions::Metadata.timedtext_to_vtt()
+      vtt = String.build do |vtt|
+        vtt << <<-END_VTT
+        WEBVTT
+        Kind: captions
+        Language: #{target_language}
+
+
+        END_VTT
+
+        vtt << "\n\n"
+
+        lines.each do |line|
+          start_time = line.start_ms
+          end_time = line.end_ms
+
+          # start_time
+          vtt << start_time.hours.to_s.rjust(2, '0')
+          vtt << ':' << start_time.minutes.to_s.rjust(2, '0')
+          vtt << ':' << start_time.seconds.to_s.rjust(2, '0')
+          vtt << '.' << start_time.milliseconds.to_s.rjust(3, '0')
+
+          vtt << " --> "
+
+          # end_time
+          vtt << end_time.hours.to_s.rjust(2, '0')
+          vtt << ':' << end_time.minutes.to_s.rjust(2, '0')
+          vtt << ':' << end_time.seconds.to_s.rjust(2, '0')
+          vtt << '.' << end_time.milliseconds.to_s.rjust(3, '0')
+
+          vtt << "\n"
+          vtt << line.line
+
+          vtt << "\n"
+          vtt << "\n"
+        end
+      end
+
+      return vtt
+    end
+
+    private def self.parse(initial_data : Hash(String, JSON::Any))
+      body = initial_data.dig("actions", 0, "updateEngagementPanelAction", "content", "transcriptRenderer",
+        "content", "transcriptSearchPanelRenderer", "body", "transcriptSegmentListRenderer",
+        "initialSegments").as_a
+
+      lines = [] of TranscriptLine
+      body.each do |line|
+        # Transcript section headers. They are not apart of the captions and as such we can safely skip them.
+        if line.as_h.has_key?("transcriptSectionHeaderRenderer")
+          next
+        end
+
+        line = line["transcriptSegmentRenderer"]
+
+        start_ms = line["startMs"].as_s.to_i.millisecond
+        end_ms = line["endMs"].as_s.to_i.millisecond
+
+        text = extract_text(line["snippet"]) || ""
+
+        lines << TranscriptLine.new(start_ms, end_ms, text)
+      end
+
+      return lines
+    end
+  end
+end

src/invidious/views/playlist.ecr

@@ -70,7 +70,12 @@
             </b>
         <% else %>
             <b>
+                <% if !author.empty? %>
                     <a href="/channel/<%= playlist.ucid %>"><%= author %></a> |
+                <% elsif !playlist.subtitle.nil? %>
+                    <% subtitle = playlist.subtitle || "" %>
+                    <span><%= HTML.escape(subtitle[0..subtitle.rindex(" • ") || subtitle.size]) %></span> |
+                <% end %>
                 <%= translate_count(locale, "generic_videos_count", playlist.video_count) %> |
                 <%= translate(locale, "Updated `x` ago", recode_date(playlist.updated, locale)) %>
             </b>

src/invidious/views/user/preferences.ecr

@@ -89,7 +89,7 @@
                 <label for="captions[0]"><%= translate(locale, "preferences_captions_label") %></label>
                 <% preferences.captions.each_with_index do |caption, index| %>
                     <select class="pure-u-1-6" name="captions[<%= index %>]" id="captions[<%= index %>]">
-                        <% Invidious::Videos::Caption::LANGUAGES.each do |option| %>
+                        <% Invidious::Videos::Captions::LANGUAGES.each do |option| %>
                             <option value="<%= option %>" <% if preferences.captions[index] == option %> selected <% end %>><%= translate(locale, option.blank? ? "none" : option) %></option>
                         <% end %>
                     </select>

src/invidious/yt_backend/youtube_api.cr

@@ -557,6 +557,30 @@ module YoutubeAPI
     return self._post_json("/youtubei/v1/search", data, client_config)
   end
 
+  ####################################################################
+  # get_transcript(params, client_config?)
+  #
+  # Requests the youtubei/v1/get_transcript endpoint with the required headers
+  # and POST data in order to get a JSON reply.
+  #
+  # The requested data is a specially encoded protobuf string that denotes the specific language requested.
+  #
+  # An optional ClientConfig parameter can be passed, too (see
+  # `struct ClientConfig` above for more details).
+  #
+
+  def get_transcript(
+    params : String,
+    client_config : ClientConfig | Nil = nil
+  ) : Hash(String, JSON::Any)
+    data = {
+      "context" => self.make_context(client_config),
+      "params"  => params,
+    }
+
+    return self._post_json("/youtubei/v1/get_transcript", data, client_config)
+  end
+
   ####################################################################
   # _post_json(endpoint, data, client_config?)
   #