Overhaul extractors.cr to use modules

src/invidious/helpers/extractors.cr

@@ -3,47 +3,34 @@
 
 # Tuple of Parsers/Extractors so we can easily cycle through them.
 private ITEM_CONTAINER_EXTRACTOR = {
-  YoutubeTabsExtractor.new,
-  SearchResultsExtractor.new,
-  ContinuationExtractor.new,
+  Extractors::YouTubeTabs,
+  Extractors::SearchResults,
+  Extractors::Continuation,
 }
 
 private ITEM_PARSERS = {
-  VideoParser.new,
-  ChannelParser.new,
-  GridPlaylistParser.new,
-  PlaylistParser.new,
-  CategoryParser.new,
+  Parsers::VideoRendererParser,
+  Parsers::ChannelRendererParser,
+  Parsers::GridPlaylistRendererParser,
+  Parsers::PlaylistRendererParser,
+  Parsers::CategoryRendererParser,
 }
 
-private struct AuthorFallback
-  property name, id
-
-  def initialize(@name : String? = nil, @id : String? = nil)
-  end
-end
+record AuthorFallback, name : String? = nil, id : String? = nil
 
 # The following are the parsers for parsing raw item data into neatly packaged structs.
 # They're accessed through the process() method which validates the given data as applicable
 # to their specific struct and then use the internal parse() method to assemble the struct
 # specific to their category.
-private abstract struct ItemParser
-  # Base type for all item parsers.
-  def process(item : JSON::Any, author_fallback : AuthorFallback)
-  end
-
-  private def parse(item_contents : JSON::Any, author_fallback : AuthorFallback)
-  end
-end
-
-private struct VideoParser < ItemParser
-  def process(item, author_fallback)
+private module Parsers
+  module VideoRendererParser
+    def self.process(item : JSON::Any, author_fallback : AuthorFallback)
       if item_contents = (item["videoRenderer"]? || item["gridVideoRenderer"]?)
         return self.parse(item_contents, author_fallback)
       end
     end
 
-  private def parse(item_contents, author_fallback)
+    private def self.parse(item_contents, author_fallback)
       video_id = item_contents["videoId"].as_s
       title = item_contents["title"].try { |t| t["simpleText"]?.try &.as_s || t["runs"]?.try &.as_a.map(&.["text"].as_s).join("") } || ""
 
@@ -94,14 +81,14 @@ private struct VideoParser < ItemParser
     end
   end
 
-private struct ChannelParser < ItemParser
-  def process(item, author_fallback)
+  module ChannelRendererParser
+    def self.process(item : JSON::Any, author_fallback : AuthorFallback)
       if item_contents = (item["channelRenderer"]? || item["gridChannelRenderer"]?)
         return self.parse(item_contents, author_fallback)
       end
     end
 
-  private def parse(item_contents, author_fallback)
+    private def self.parse(item_contents, author_fallback)
       author = item_contents["title"]["simpleText"]?.try &.as_s || author_fallback.name || ""
       author_id = item_contents["channelId"]?.try &.as_s || author_fallback.id || ""
 
@@ -125,14 +112,14 @@ private struct ChannelParser < ItemParser
     end
   end
 
-private struct GridPlaylistParser < ItemParser
-  def process(item, author_fallback)
+  module GridPlaylistRendererParser
+    def self.process(item : JSON::Any, author_fallback : AuthorFallback)
       if item_contents = item["gridPlaylistRenderer"]?
         return self.parse(item_contents, author_fallback)
       end
     end
 
-  private def parse(item_contents, author_fallback)
+    private def self.parse(item_contents, author_fallback)
       title = item_contents["title"]["runs"].as_a[0]?.try &.["text"].as_s || ""
       plid = item_contents["playlistId"]?.try &.as_s || ""
 
@@ -151,14 +138,14 @@ private struct GridPlaylistParser < ItemParser
     end
   end
 
-private struct PlaylistParser < ItemParser
-  def process(item, author_fallback)
+  module PlaylistRendererParser
+    def self.process(item : JSON::Any, author_fallback : AuthorFallback)
       if item_contents = item["playlistRenderer"]?
         return self.parse(item_contents, author_fallback)
       end
     end
 
-  def parse(item_contents, author_fallback)
+    private def self.parse(item_contents, author_fallback)
       title = item_contents["title"]["simpleText"]?.try &.as_s || ""
       plid = item_contents["playlistId"]?.try &.as_s || ""
 
@@ -195,14 +182,14 @@ private struct PlaylistParser < ItemParser
     end
   end
 
-private struct CategoryParser < ItemParser
-  def process(item, author_fallback)
+  module CategoryRendererParser
+    def self.process(item : JSON::Any, author_fallback : AuthorFallback)
       if item_contents = item["shelfRenderer"]?
         return self.parse(item_contents, author_fallback)
       end
     end
 
-  def parse(item_contents, author_fallback)
+    private def self.parse(item_contents, author_fallback)
       # Title extraction is a bit complicated. There are two possible routes for it
       # as well as times when the title attribute just isn't sent by YT.
       title_container = item_contents["title"]? || ""
@@ -256,28 +243,22 @@ private struct CategoryParser < ItemParser
       })
     end
   end
+end
 
 # The following are the extractors for extracting an array of items from
 # the internal Youtube API's JSON response. The result is then packaged into
 # a structure we can more easily use via the parsers above. Their internals are
 # identical to the item parsers.
 
-private abstract struct ItemsContainerExtractor
-  def process(item : Hash(String, JSON::Any))
-  end
-
-  private def extract(target : JSON::Any)
-  end
-end
-
-private struct YoutubeTabsExtractor < ItemsContainerExtractor
-  def process(initial_data)
+private module Extractors
+  module YouTubeTabs
+    def self.process(initial_data : Hash(String, JSON::Any))
       if target = initial_data["twoColumnBrowseResultsRenderer"]?
         self.extract(target)
       end
     end
 
-  private def extract(target)
+    private def self.extract(target)
       raw_items = [] of JSON::Any
       selected_tab = extract_selected_tab(target["tabs"])
       content = selected_tab["content"]
@@ -304,14 +285,14 @@ private struct YoutubeTabsExtractor < ItemsContainerExtractor
     end
   end
 
-private struct SearchResultsExtractor < ItemsContainerExtractor
-  def process(initial_data)
+  module SearchResults
+    def self.process(initial_data : Hash(String, JSON::Any))
       if target = initial_data["twoColumnSearchResultsRenderer"]?
         self.extract(target)
       end
     end
 
-  private def extract(target)
+    private def self.extract(target)
       raw_items = [] of Array(JSON::Any)
       content = target["primaryContents"]
       renderer = content["sectionListRenderer"]["contents"].as_a.each do |node|
@@ -326,8 +307,8 @@ private struct SearchResultsExtractor < ItemsContainerExtractor
     end
   end
 
-private struct ContinuationExtractor < ItemsContainerExtractor
-  def process(initial_data)
+  module Continuation
+    def self.process(initial_data : Hash(String, JSON::Any))
       if target = initial_data["continuationContents"]?
         self.extract(target)
       elsif target = initial_data["appendContinuationItemsAction"]?
@@ -335,7 +316,7 @@ private struct ContinuationExtractor < ItemsContainerExtractor
       end
     end
 
-  private def extract(target)
+    private def self.extract(target)
       raw_items = [] of JSON::Any
       if content = target["gridContinuation"]?
         raw_items = content["items"].as_a
@@ -346,6 +327,7 @@ private struct ContinuationExtractor < ItemsContainerExtractor
       return raw_items
     end
   end
+end
 
 # Parses an item from Youtube's JSON response into a more usable structure.
 # The end result can either be a SearchVideo, SearchPlaylist or SearchChannel.