diff options
Diffstat (limited to 'MediaBrowser.Api/Streaming/BaseHlsPlaylistHandler.cs')
| -rw-r--r-- | MediaBrowser.Api/Streaming/BaseHlsPlaylistHandler.cs | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/MediaBrowser.Api/Streaming/BaseHlsPlaylistHandler.cs b/MediaBrowser.Api/Streaming/BaseHlsPlaylistHandler.cs new file mode 100644 index 000000000..94a8f7926 --- /dev/null +++ b/MediaBrowser.Api/Streaming/BaseHlsPlaylistHandler.cs @@ -0,0 +1,221 @@ +using MediaBrowser.Common.Extensions; +using MediaBrowser.Common.IO; +using MediaBrowser.Common.Net; +using MediaBrowser.Common.Net.Handlers; +using MediaBrowser.Controller.Entities; +using MediaBrowser.Model.Entities; +using System; +using System.IO; +using System.Linq; +using System.Net; +using System.Text; +using System.Threading.Tasks; + +namespace MediaBrowser.Api.Streaming +{ + /// <summary> + /// Class BaseHlsPlaylistHandler + /// </summary> + /// <typeparam name="TBaseItemType">The type of the T base item type.</typeparam> + public abstract class BaseHlsPlaylistHandler<TBaseItemType> : BaseStreamingHandler<TBaseItemType> + where TBaseItemType : BaseItem, IHasMediaStreams, new() + { + /// <summary> + /// Gets the audio arguments. + /// </summary> + /// <returns>System.String.</returns> + protected abstract string GetAudioArguments(); + /// <summary> + /// Gets the video arguments. + /// </summary> + /// <returns>System.String.</returns> + protected abstract string GetVideoArguments(); + + /// <summary> + /// Gets the type of the transcoding job. + /// </summary> + /// <value>The type of the transcoding job.</value> + protected override TranscodingJobType TranscodingJobType + { + get { return TranscodingJobType.Hls; } + } + + /// <summary> + /// This isn't needed because we're going to override the whole flow using ProcessRequest + /// </summary> + /// <param name="stream">The stream.</param> + /// <param name="responseInfo">The response info.</param> + /// <param name="contentLength">Length of the content.</param> + /// <returns>Task.</returns> + /// <exception cref="NotImplementedException"></exception> + protected override Task WriteResponseToOutputStream(Stream stream, ResponseInfo responseInfo, long? contentLength) + { + throw new NotImplementedException(); + } + + /// <summary> + /// Gets the segment file extension. + /// </summary> + /// <value>The segment file extension.</value> + protected abstract string SegmentFileExtension { get; } + + /// <summary> + /// Processes the request. + /// </summary> + /// <param name="ctx">The CTX.</param> + /// <returns>Task.</returns> + public override async Task ProcessRequest(HttpListenerContext ctx) + { + HttpListenerContext = ctx; + + var playlist = OutputFilePath; + var isPlaylistNewlyCreated = false; + + // If the playlist doesn't already exist, startup ffmpeg + if (!File.Exists(playlist)) + { + isPlaylistNewlyCreated = true; + await StartFFMpeg(playlist).ConfigureAwait(false); + } + else + { + Plugin.Instance.OnTranscodeBeginRequest(playlist, TranscodingJobType.Hls); + } + + // Get the current playlist text and convert to bytes + var playlistText = await GetPlaylistFileText(playlist, isPlaylistNewlyCreated).ConfigureAwait(false); + + var content = Encoding.UTF8.GetBytes(playlistText); + + var stream = new MemoryStream(content); + + try + { + // Dump the stream off to the static file handler to serve statically + await new StaticFileHandler(Kernel) { ContentType = MimeTypes.GetMimeType("playlist.m3u8"), SourceStream = stream }.ProcessRequest(ctx); + } + finally + { + Plugin.Instance.OnTranscodeEndRequest(playlist, TranscodingJobType.Hls); + } + } + + /// <summary> + /// Gets the current playlist text + /// </summary> + /// <param name="playlist">The path to the playlist</param> + /// <param name="waitForMinimumSegments">Whether or not we should wait until it contains three segments</param> + /// <returns>Task{System.String}.</returns> + private async Task<string> GetPlaylistFileText(string playlist, bool waitForMinimumSegments) + { + string fileText; + + while (true) + { + // Need to use FileShare.ReadWrite because we're reading the file at the same time it's being written + using (var fileStream = new FileStream(playlist, FileMode.Open, FileAccess.Read, FileShare.ReadWrite, StreamDefaults.DefaultFileStreamBufferSize, FileOptions.Asynchronous)) + { + using (var reader = new StreamReader(fileStream)) + { + fileText = await reader.ReadToEndAsync().ConfigureAwait(false); + } + } + + if (!waitForMinimumSegments || CountStringOccurrences(fileText, "#EXTINF:") >= 3) + { + break; + } + + await Task.Delay(25).ConfigureAwait(false); + } + + // The segement paths within the playlist are phsyical, so strip that out to make it relative + fileText = fileText.Replace(Path.GetDirectoryName(playlist) + Path.DirectorySeparatorChar, string.Empty); + + // Even though we specify target duration of 9, ffmpeg seems unable to keep all segments under that amount + fileText = fileText.Replace("#EXT-X-TARGETDURATION:9", "#EXT-X-TARGETDURATION:10"); + + // It's considered live while still encoding (EVENT). Once the encoding has finished, it's video on demand (VOD). + var playlistType = fileText.IndexOf("#EXT-X-ENDLIST", StringComparison.OrdinalIgnoreCase) == -1 ? "EVENT" : "VOD"; + + // Add event type at the top + fileText = fileText.Replace("#EXT-X-ALLOWCACHE", "#EXT-X-PLAYLIST-TYPE:" + playlistType + Environment.NewLine + "#EXT-X-ALLOWCACHE"); + + return fileText; + } + + /// <summary> + /// Count occurrences of strings. + /// </summary> + /// <param name="text">The text.</param> + /// <param name="pattern">The pattern.</param> + /// <returns>System.Int32.</returns> + private static int CountStringOccurrences(string text, string pattern) + { + // Loop through all instances of the string 'text'. + var count = 0; + var i = 0; + while ((i = text.IndexOf(pattern, i, StringComparison.OrdinalIgnoreCase)) != -1) + { + i += pattern.Length; + count++; + } + return count; + } + + /// <summary> + /// Gets all command line arguments to pass to ffmpeg + /// </summary> + /// <param name="outputPath">The playlist output path</param> + /// <param name="isoMount">The iso mount.</param> + /// <returns>System.String.</returns> + protected override string GetCommandLineArguments(string outputPath, IIsoMount isoMount) + { + var segmentOutputPath = Path.GetDirectoryName(outputPath); + var segmentOutputName = HlsSegmentHandler.SegmentFilePrefix + Path.GetFileNameWithoutExtension(outputPath); + + segmentOutputPath = Path.Combine(segmentOutputPath, segmentOutputName + "%03d." + SegmentFileExtension.TrimStart('.')); + + var probeSize = Kernel.FFMpegManager.GetProbeSizeArgument(LibraryItem); + + return string.Format("{0} {1} -i {2}{3} -threads 0 {4} {5} {6} -f ssegment -segment_list_flags +live -segment_time 9 -segment_list \"{7}\" \"{8}\"", + probeSize, + FastSeekCommandLineParameter, + GetInputArgument(isoMount), + SlowSeekCommandLineParameter, + MapArgs, + GetVideoArguments(), + GetAudioArguments(), + outputPath, + segmentOutputPath + ).Trim(); + } + + /// <summary> + /// Deletes the partial stream files. + /// </summary> + /// <param name="playlistFilePath">The playlist file path.</param> + protected override void DeletePartialStreamFiles(string playlistFilePath) + { + var directory = Path.GetDirectoryName(playlistFilePath); + var name = Path.GetFileNameWithoutExtension(playlistFilePath); + + var filesToDelete = Directory.EnumerateFiles(directory, "*", SearchOption.TopDirectoryOnly) + .Where(f => f.IndexOf(name, StringComparison.OrdinalIgnoreCase) != -1) + .ToList(); + + foreach (var file in filesToDelete) + { + try + { + Logger.Info("Deleting HLS file {0}", file); + File.Delete(file); + } + catch (IOException ex) + { + Logger.ErrorException("Error deleting HLS file {0}", ex, file); + } + } + } + } +} |