/// <summary>
/// Gets video by ID
/// </summary>
public async Task <Video> GetVideoAsync(string videoId)
{
videoId.GuardNotNull(nameof(videoId));
if (!ValidateVideoId(videoId))
{
throw new ArgumentException("Invalid Youtube video ID", nameof(videoId));
}
// Get player context
var context = await GetPlayerContextAsync(videoId).ConfigureAwait(false);
// Get video info
var request = $"{YoutubeHost}/get_video_info?video_id={videoId}&sts={context.Sts}&el=info&ps=default&hl=en";
var response = await _httpService.GetStringAsync(request).ConfigureAwait(false);
var videoDic = UrlHelper.GetDictionaryFromUrlQuery(response);
// Check error code
if (videoDic.ContainsKey("errorcode"))
{
var errorCode = videoDic.Get("errorcode").ParseInt();
var errorReason = videoDic.Get("reason");
throw new VideoNotAvailableException(videoId, errorCode, errorReason);
}
// Check if video requires purchase
if (videoDic.GetOrDefault("requires_purchase") == "1")
{
var previewVideoId = videoDic.Get("ypc_vid");
throw new VideoRequiresPurchaseException(videoId, previewVideoId);
}
// Parse metadata
var title = videoDic.Get("title");
var duration = TimeSpan.FromSeconds(videoDic.Get("length_seconds").ParseDouble());
var viewCount = videoDic.Get("view_count").ParseLong();
var keywords = videoDic.Get("keywords").Split(",");
var isListed = videoDic.GetOrDefault("is_listed") == "1"; // unlisted videos don't have this
var isRatingAllowed = videoDic.Get("allow_ratings") == "1";
var isMuted = videoDic.Get("muted") == "1";
var isEmbeddingAllowed = videoDic.Get("allow_embed") == "1";
// Prepare stream info collections
var muxedStreamInfos = new List <MuxedStreamInfo>();
var audioStreamInfos = new List <AudioStreamInfo>();
var videoStreamInfos = new List <VideoStreamInfo>();
// Resolve muxed streams
var muxedStreamInfosEncoded = videoDic.GetOrDefault("url_encoded_fmt_stream_map");
if (muxedStreamInfosEncoded.IsNotBlank())
{
await ResolveMuxedStreamInfosAsync(context, muxedStreamInfosEncoded, muxedStreamInfos)
.ConfigureAwait(false);
}
// Resolve adaptive streams
var adaptiveStreamInfosEncoded = videoDic.GetOrDefault("adaptive_fmts");
if (adaptiveStreamInfosEncoded.IsNotBlank())
{
await ResolveAdaptiveStreamInfosAsync(context, adaptiveStreamInfosEncoded,
audioStreamInfos, videoStreamInfos)
.ConfigureAwait(false);
}
// Resolve dash streams
var dashManifestUrl = videoDic.GetOrDefault("dashmpd");
if (dashManifestUrl.IsNotBlank())
{
await ResolveDashStreamInfosAsync(context, dashManifestUrl,
audioStreamInfos, videoStreamInfos)
.ConfigureAwait(false);
}
// Finalize stream info collections
muxedStreamInfos = muxedStreamInfos.Distinct(s => s.Itag).OrderByDescending(s => s.VideoQuality).ToList();
audioStreamInfos = audioStreamInfos.Distinct(s => s.Itag).OrderByDescending(s => s.Bitrate).ToList();
videoStreamInfos = videoStreamInfos.Distinct(s => s.Itag).OrderByDescending(s => s.VideoQuality).ToList();
// Parse closed caption tracks
var closedCaptionTrackInfos = new List <ClosedCaptionTrackInfo>();
var closedCaptionTrackInfosEncoded = videoDic.GetOrDefault("caption_tracks");
if (closedCaptionTrackInfosEncoded.IsNotBlank())
{
ParseClosedCaptionTrackInfos(closedCaptionTrackInfosEncoded, closedCaptionTrackInfos);
}
// Get metadata extension
request = $"{YoutubeHost}/get_video_metadata?video_id={videoId}";
response = await _httpService.GetStringAsync(request).ConfigureAwait(false);
var videoXml = XElement.Parse(response).StripNamespaces().ElementStrict("html_content");
// Parse metadata extension
var description = videoXml.ElementStrict("video_info").ElementStrict("description").Value;
var likeCount = (long)videoXml.ElementStrict("video_info").ElementStrict("likes_count_unformatted");
var dislikeCount = (long)videoXml.ElementStrict("video_info").ElementStrict("dislikes_count_unformatted");
// Parse author info
var authorId = videoXml.ElementStrict("user_info").ElementStrict("channel_external_id").Value;
var authorName = videoXml.ElementStrict("user_info").ElementStrict("username").Value;
var authorTitle = videoXml.ElementStrict("user_info").ElementStrict("channel_title").Value;
var authorIsPaid = videoXml.ElementStrict("user_info").ElementStrict("channel_paid").Value == "1";
var authorLogoUrl = videoXml.ElementStrict("user_info").ElementStrict("channel_logo_url").Value;
var authorBannerUrl = videoXml.ElementStrict("user_info").ElementStrict("channel_banner_url").Value;
// Concat metadata
var author = new Channel(authorId, authorName, authorTitle, authorIsPaid, authorLogoUrl, authorBannerUrl);
var thumbnails = new VideoThumbnails(videoId);
var status = new VideoStatus(isListed, isRatingAllowed, isMuted, isEmbeddingAllowed);
var statistics = new Statistics(viewCount, likeCount, dislikeCount);
return(new Video(videoId, author, title, description, thumbnails, duration, keywords, status, statistics,
muxedStreamInfos, audioStreamInfos, videoStreamInfos, closedCaptionTrackInfos));
}
/// <summary>
/// Gets playlist by ID, truncating resulting video list at given number of pages (1 page ≤ 200 videos)
/// </summary>
public async Task <Playlist> GetPlaylistAsync(string playlistId, int maxPages)
{
playlistId.GuardNotNull(nameof(playlistId));
maxPages.GuardPositive(nameof(maxPages));
if (!ValidatePlaylistId(playlistId))
{
throw new ArgumentException("Invalid Youtube playlist ID", nameof(playlistId));
}
// Get all videos across pages
var pagesDone = 0;
var offset = 0;
XElement playlistXml;
var videoIds = new HashSet <string>();
var videos = new List <PlaylistVideo>();
do
{
// Get manifest
var request = $"{YoutubeHost}/list_ajax?style=xml&action_get_list=1&list={playlistId}&index={offset}";
var response = await _httpService.GetStringAsync(request).ConfigureAwait(false);
playlistXml = XElement.Parse(response).StripNamespaces();
// Parse videos
var total = 0;
var delta = 0;
foreach (var videoXml in playlistXml.Elements("video"))
{
// Basic info
var videoId = videoXml.ElementStrict("encrypted_id").Value;
var videoTitle = videoXml.ElementStrict("title").Value;
var videoThumbnails = new VideoThumbnails(videoId);
var videoDuration = TimeSpan.FromSeconds((double)videoXml.ElementStrict("length_seconds"));
var videoDescription = videoXml.ElementStrict("description").Value;
// Keywords
var videoKeywordsJoined = videoXml.ElementStrict("keywords").Value;
var videoKeywords = Regex
.Matches(videoKeywordsJoined, @"(?<=(^|\s)(?<q>""?))([^""]|(""""))*?(?=\<q>(?=\s|$))")
.Cast <Match>()
.Select(m => m.Value)
.Where(s => s.IsNotBlank())
.ToArray();
// Statistics
// The inner text is already formatted so we have to parse it manually
var videoViewCount =
Regex.Replace(videoXml.ElementStrict("views").Value, @"\D", "").ParseLong();
var videoLikeCount =
Regex.Replace(videoXml.ElementStrict("likes").Value, @"\D", "").ParseLong();
var videoDislikeCount =
Regex.Replace(videoXml.ElementStrict("dislikes").Value, @"\D", "").ParseLong();
var videoStatistics = new Statistics(videoViewCount, videoLikeCount, videoDislikeCount);
// Video
var video = new PlaylistVideo(videoId, videoTitle, videoDescription, videoThumbnails, videoDuration,
videoKeywords, videoStatistics);
// Add to list if not already there
if (videoIds.Add(video.Id))
{
videos.Add(video);
delta++;
}
total++;
}
// Break if the videos started repeating
if (delta <= 0)
{
break;
}
// Prepare for next page
pagesDone++;
offset += total;
} while (pagesDone < maxPages);
// Basic info
var title = playlistXml.ElementStrict("title").Value;
var author = playlistXml.Element("author")?.Value ?? ""; // system playlists don't have an author
var description = playlistXml.ElementStrict("description").Value;
// Statistics
var viewCount = (long?)playlistXml.Element("views") ?? 0; // watchlater does not have views
var likeCount = (long?)playlistXml.Element("likes") ?? 0; // system playlists don't have likes
var dislikeCount = (long?)playlistXml.Element("dislikes") ?? 0; // system playlists don't have dislikes
var statistics = new Statistics(viewCount, likeCount, dislikeCount);
return(new Playlist(playlistId, title, author, description, statistics, videos));
}
