Switch to innertube API for videos (#2220)

Commit history:
- Switch to innertube API for videos
- fix hardcoded strings + fix bypass geo-restriction

src/invidious/videos.cr

@@ -525,10 +525,6 @@ struct Video
     info["microformat"].as_h["playerMicroformatRenderer"].as_h["publishDate"] = JSON::Any.new(other.to_s("%Y-%m-%d"))
   end
 
-  def cookie
-    info["cookie"]?.try &.as_h.map { |k, v| "#{k}=#{v}" }.join("; ") || ""
-  end
-
   def allow_ratings
     r = info["videoDetails"]["allowRatings"]?.try &.as_bool
     r.nil? ? false : r
@@ -773,10 +769,6 @@ struct Video
   def reason : String?
     info["reason"]?.try &.as_s
   end
-
-  def session_token : String?
-    info["sessionToken"]?.try &.as_s?
-  end
 end
 
 struct Caption
@@ -820,44 +812,53 @@ def parse_related(r : JSON::Any) : JSON::Any?
   JSON::Any.new(rv)
 end
 
-def extract_polymer_config(body)
+def extract_video_info(video_id : String, proxy_region : String? = nil)
   params = {} of String => JSON::Any
-  player_response = body.match(/(window\["ytInitialPlayerResponse"\]|var\sytInitialPlayerResponse)\s*=\s*(?<info>{.*?});\s*var\s*meta/m)
-    .try { |r| JSON.parse(r["info"]).as_h }
 
-  if body.includes?("To continue with your YouTube experience, please fill out the form below.") ||
-     body.includes?("https://www.google.com/sorry/index")
-    params["reason"] = JSON::Any.new("Could not extract video info. Instance is likely blocked.")
-  elsif !player_response
-    params["reason"] = JSON::Any.new("Video unavailable.")
-  elsif player_response["playabilityStatus"]?.try &.["status"]?.try &.as_s != "OK"
-    reason = player_response["playabilityStatus"]["errorScreen"]?.try &.["playerErrorMessageRenderer"]?.try &.["subreason"]?.try { |s| s["simpleText"]?.try &.as_s || s["runs"].as_a.map { |r| r["text"] }.join("") } ||
-             player_response["playabilityStatus"]["reason"].as_s
+  client_config = YoutubeAPI::ClientConfig.new(proxy_region: proxy_region)
+  player_response = YoutubeAPI.player(video_id: video_id, params: "", client_config: client_config)
+
+  if player_response["playabilityStatus"]?.try &.["status"]?.try &.as_s != "OK"
+    reason = player_response["playabilityStatus"]["errorScreen"]?.try &.["playerErrorMessageRenderer"]?.try &.["subreason"]?.try { |s|
+      s["simpleText"]?.try &.as_s || s["runs"].as_a.map { |r| r["text"] }.join("")
+    } || player_response["playabilityStatus"]["reason"].as_s
     params["reason"] = JSON::Any.new(reason)
   end
 
-  session_token_json_encoded = body.match(/"XSRF_TOKEN":"(?<session_token>[^"]+)"/).try &.["session_token"]? || ""
-  params["sessionToken"] = JSON.parse(%({"key": "#{session_token_json_encoded}"}))["key"]
-  params["shortDescription"] = JSON::Any.new(body.match(/"og:description" content="(?<description>[^"]+)"/).try &.["description"]?)
+  params["shortDescription"] = player_response.dig?("videoDetails", "shortDescription") || JSON::Any.new(nil)
 
-  return params if !player_response
+  # Don't fetch the next endpoint if the video is unavailable.
+  if !params["reason"]?
+    next_response = YoutubeAPI.next({"videoId": video_id, "params": ""})
+    player_response = player_response.merge(next_response)
+  end
+
+  # Fetch the video streams using an Android client in order to get the decrypted URLs and
+  # maybe fix throttling issues (#2194).See for the explanation about the decrypted URLs:
+  # https://github.com/TeamNewPipe/NewPipeExtractor/issues/562
+  if !params["reason"]?
+    client_config.client_type = YoutubeAPI::ClientType::Android
+    stream_data = YoutubeAPI.player(video_id: video_id, params: "", client_config: client_config)
+    params["streamingData"] = stream_data["streamingData"]? || JSON::Any.new("")
+  end
 
   {"captions", "microformat", "playabilityStatus", "storyboards", "videoDetails"}.each do |f|
     params[f] = player_response[f] if player_response[f]?
   end
 
-  yt_initial_data = extract_initial_data(body)
+  params["relatedVideos"] = (
+    player_response
+      .dig?("playerOverlays", "playerOverlayRenderer", "endScreen", "watchNextEndScreenRenderer", "results")
+      .try &.as_a.compact_map { |r| parse_related r } || \
+       player_response
+        .dig?("webWatchNextResponseExtensionData", "relatedVideoArgs")
+        .try &.as_s.split(",").map { |r|
+          r = HTTP::Params.parse(r).to_h
+          JSON::Any.new(Hash.zip(r.keys, r.values.map { |v| JSON::Any.new(v) }))
+        }
+  ).try { |a| JSON::Any.new(a) } || JSON::Any.new([] of JSON::Any)
 
-  params["relatedVideos"] = yt_initial_data.try &.["playerOverlays"]?.try &.["playerOverlayRenderer"]?
-    .try &.["endScreen"]?.try &.["watchNextEndScreenRenderer"]?.try &.["results"]?.try &.as_a.compact_map { |r|
-      parse_related r
-    }.try { |a| JSON::Any.new(a) } || yt_initial_data.try &.["webWatchNextResponseExtensionData"]?.try &.["relatedVideoArgs"]?
-    .try &.as_s.split(",").map { |r|
-      r = HTTP::Params.parse(r).to_h
-      JSON::Any.new(Hash.zip(r.keys, r.values.map { |v| JSON::Any.new(v) }))
-    }.try { |a| JSON::Any.new(a) } || JSON::Any.new([] of JSON::Any)
-
-  primary_results = yt_initial_data.try &.["contents"]?.try &.["twoColumnWatchNextResults"]?.try &.["results"]?
+  primary_results = player_response.try &.["contents"]?.try &.["twoColumnWatchNextResults"]?.try &.["results"]?
     .try &.["results"]?.try &.["contents"]?
   sentiment_bar = primary_results.try &.as_a.select { |object| object["videoPrimaryInfoRenderer"]? }[0]?
     .try &.["videoPrimaryInfoRenderer"]?
@@ -917,20 +918,6 @@ def extract_polymer_config(body)
   params["subCountText"] = JSON::Any.new(author_info.try &.["subscriberCountText"]?
     .try { |t| t["simpleText"]? || t["runs"]?.try &.[0]?.try &.["text"]? }.try &.as_s.split(" ", 2)[0] || "-")
 
-  initial_data = body.match(/ytplayer\.config\s*=\s*(?<info>.*?);ytplayer\.web_player_context_config/)
-    .try { |r| JSON.parse(r["info"]) }.try &.["args"]["player_response"]?
-    .try &.as_s?.try &.try { |r| JSON.parse(r).as_h }
-
-  if initial_data
-    {"playabilityStatus", "streamingData"}.each do |f|
-      params[f] = initial_data[f] if initial_data[f]?
-    end
-  else
-    {"playabilityStatus", "streamingData"}.each do |f|
-      params[f] = player_response[f] if player_response[f]?
-    end
-  end
-
   params
 end
 
@@ -961,26 +948,19 @@ def get_video(id, db, refresh = true, region = nil, force_refresh = false)
 end
 
 def fetch_video(id, region)
-  response = YT_POOL.client(region, &.get("/watch?v=#{id}&gl=US&hl=en&has_verified=1&bpctr=9999999999"))
+  info = extract_video_info(video_id: id)
 
-  if md = response.headers["location"]?.try &.match(/v=(?<id>[a-zA-Z0-9_-]{11})/)
-    raise VideoRedirect.new(video_id: md["id"])
-  end
-
-  info = extract_polymer_config(response.body)
-  info["cookie"] = JSON::Any.new(response.cookies.to_h.transform_values { |v| JSON::Any.new(v.value) })
-  allowed_regions = info["microformat"]?.try &.["playerMicroformatRenderer"]["availableCountries"]?.try &.as_a.map &.as_s || [] of String
+  allowed_regions = info
+    .dig?("microformat", "playerMicroformatRenderer", "availableCountries")
+    .try &.as_a.map &.as_s || [] of String
 
   # Check for region-blocks
   if info["reason"]?.try &.as_s.includes?("your country")
     bypass_regions = PROXY_LIST.keys & allowed_regions
     if !bypass_regions.empty?
       region = bypass_regions[rand(bypass_regions.size)]
-      response = YT_POOL.client(region, &.get("/watch?v=#{id}&gl=US&hl=en&has_verified=1&bpctr=9999999999"))
-
-      region_info = extract_polymer_config(response.body)
+      region_info = extract_video_info(video_id: id, proxy_region: region)
       region_info["region"] = JSON::Any.new(region) if region
-      region_info["cookie"] = JSON::Any.new(response.cookies.to_h.transform_values { |v| JSON::Any.new(v.value) })
       info = region_info if !region_info["reason"]?
     end
   end