Migrate audio transcoding from DASH to a single AAC (.m4a) file

Application/Configuration/StreamGatewayConfiguration.cs

@@ -11,6 +11,6 @@ namespace Musify.Application.Configuration
         public required string PublicBaseUrl { get; set; }
 
         [Required]
-        public string ManifestFileName { get; set; } = "manifest.mpd";
+        public string AudioFileName { get; set; } = "audio.m4a";
     }
 }

Application/Contracts/IAudioTranscoderService.cs

@@ -2,7 +2,7 @@ namespace Musify.Application.Contracts
 {
     public interface IAudioTranscoderService
     {
-        Task<int> TranscodeToDashAsync(Stream audioStream, string destinationPath, CancellationToken cancellationToken);
+        Task<int> TranscodeToAudioFileAsync(Stream audioStream, string destinationPath, CancellationToken cancellationToken);
 
         Task<bool> IsValidAudioFileAsync(string filePath, CancellationToken cancellationToken);
     }

Application/Tracks/Handlers/GetTrackStreamQueryHandler.cs

@@ -44,7 +44,7 @@ namespace Musify.Application.Tracks.Handlers
                 streamGatewayConfiguration.PublicBaseUrl.TrimEnd('/'),
                 "media",
                 folderPath,
-                streamGatewayConfiguration.ManifestFileName);
+                streamGatewayConfiguration.AudioFileName);
 
             logger.LogInformation("Issued stream ticket for track {TrackId} to user {UserId}", request.TrackId, request.UserId);
 

Infrastructure/Configuration/AudioTranscoderConfiguration.cs

@@ -19,7 +19,7 @@ namespace Musify.Infrastructure.Configuration
         public string ExecutableName { get; set; } = "ffmpeg";
 
         [Required]
-        public string ManifestFileName { get; set; } = "manifest.mpd";
+        public string OutputFileName { get; set; } = "audio.m4a";
 
         [Required]
         public string AudioCodec { get; set; } = "aac";
@@ -36,15 +36,6 @@ namespace Musify.Infrastructure.Configuration
         [Required]
         public string AudioProfile { get; set; } = "aac_low";
 
-        [Range(1, 60)]
-        public int SegmentDurationSeconds { get; set; } = 4;
-
-        [Required]
-        public string InitSegmentName { get; set; } = "init-stream$RepresentationID$.m4s";
-
-        [Required]
-        public string MediaSegmentName { get; set; } = "chunk-stream$RepresentationID$-$Number$.m4s";
-
         public string AdditionalArguments { get; set; } = string.Empty;
     }
 }

Infrastructure/MassTransit/Activities/Audio/TranscodeAudioActivity.cs

@@ -9,15 +9,15 @@ using Musify.Infrastructure.MassTransit.Logs;
 
 namespace Musify.Infrastructure.MassTransit.Activities
 {
-    internal class TranscodeDashAudioActivity(
+    internal class TranscodeAudioActivity(
         IDatabase database,
         IAudioTranscoderService audioTranscoder,
-        ILogger<TranscodeDashAudioActivity> logger)
+        ILogger<TranscodeAudioActivity> logger)
-        : IActivity<TranscodeDashAudioArguments, TranscodeDashAudioLog>
+        : IActivity<TranscodeAudioArguments, TranscodeAudioLog>
     {
-        public const string ExecuteEndpointName = "transcode-dash-audio";
+        public const string ExecuteEndpointName = "transcode-audio";
 
-        public async Task<ExecutionResult> Execute(ExecuteContext<TranscodeDashAudioArguments> executeContext)
+        public async Task<ExecutionResult> Execute(ExecuteContext<TranscodeAudioArguments> executeContext)
         {
             var sourceFilePath = executeContext.GetVariable<string>(executeContext.Arguments.SourceFilePathVariable);
             ArgumentNullException.ThrowIfNull(sourceFilePath, nameof(sourceFilePath));
@@ -40,7 +40,7 @@ namespace Musify.Infrastructure.MassTransit.Activities
             {
                 await using (var fileStream = File.OpenRead(sourceFilePath))
                 {
-                    await audioTranscoder.TranscodeToDashAsync(
+                    await audioTranscoder.TranscodeToAudioFileAsync(
                         fileStream,
                         workingDirectory,
                         executeContext.CancellationToken);
@@ -68,7 +68,7 @@ namespace Musify.Infrastructure.MassTransit.Activities
             }
         }
 
-        public Task<CompensationResult> Compensate(CompensateContext<TranscodeDashAudioLog> compensateContext)
+        public Task<CompensationResult> Compensate(CompensateContext<TranscodeAudioLog> compensateContext)
         {
             try
             {
@@ -86,4 +86,4 @@ namespace Musify.Infrastructure.MassTransit.Activities
             }
         }
     }
-}
+}

Infrastructure/MassTransit/Arguments/TranscodeAudioArguments.cs

@@ -1,7 +1,7 @@
-namespace Musify.Infrastructure.MassTransit.Arguments
+namespace Musify.Infrastructure.MassTransit.Arguments
 {
-    public record TranscodeDashAudioArguments(
+    public record TranscodeAudioArguments(
         Guid TrackId,
         string SourceFilePathVariable,
         string WorkingDirectoryVariable);
-}
+}

Infrastructure/MassTransit/DependencyInjection/MassTransitDependencyInjection.Registration.cs

@@ -52,7 +52,7 @@ namespace Musify.Infrastructure.MassTransit
             options.AddActivity<UpdatePlayListPictureActivity, UpdatePlayListPictureArguments, UpdatePlayListPictureLog>();
             options.AddActivity<UpdateTrackPictureActivity, UpdateTrackPictureArguments, UpdateTrackPictureLog>();
             options.AddActivity<DownloadFileFromBucketActivity, DownloadFileFromBucketArguments, DownloadFileFromBucketLog>();
-            options.AddActivity<TranscodeDashAudioActivity, TranscodeDashAudioArguments, TranscodeDashAudioLog>();
+            options.AddActivity<TranscodeAudioActivity, TranscodeAudioArguments, TranscodeAudioLog>();
             options.AddActivity<TransferFilesToBucketActivity, TransferFilesToBucketArguments, TransferFilesToBucketLog>();
             options.AddActivity<UpdateTrackAudioActivity, UpdateTrackAudioArguments, UpdateTrackAudioLog>();
             options.AddActivity<UploadFileToBucketActivity, UploadFileToBucketArguments, UploadFileToBucketLog>();
@@ -178,10 +178,10 @@ namespace Musify.Infrastructure.MassTransit
                 busRegistrationContext,
                 DownloadFileFromBucketActivity.ExecuteEndpointName);
 
-            ConfigureActivityEndpoint<TranscodeDashAudioActivity, TranscodeDashAudioArguments, TranscodeDashAudioLog>(
+            ConfigureActivityEndpoint<TranscodeAudioActivity, TranscodeAudioArguments, TranscodeAudioLog>(
                 busFactoryConfigurator,
                 busRegistrationContext,
-                TranscodeDashAudioActivity.ExecuteEndpointName);
+                TranscodeAudioActivity.ExecuteEndpointName);
 
             ConfigureActivityEndpoint<TransferFilesToBucketActivity, TransferFilesToBucketArguments, TransferFilesToBucketLog>(
                 busFactoryConfigurator,

Infrastructure/MassTransit/Logs/TranscodeAudioLog.cs

@@ -0,0 +1,4 @@
+namespace Musify.Infrastructure.MassTransit.Logs
+{
+    public record TranscodeAudioLog(string WorkingDirectory);
+}

Infrastructure/MassTransit/Logs/TranscodeDashAudioLog.cs

@@ -1,4 +0,0 @@
-namespace Musify.Infrastructure.MassTransit.Logs
-{
-    public record TranscodeDashAudioLog(string WorkingDirectory);
-}

Infrastructure/MassTransit/RoutingSlip/Builders/AudioWorkflowRoutingSlipBuilder.cs

@@ -39,8 +39,8 @@ namespace Musify.Infrastructure.MassTransit.RoutingSlip.Builders
 
             routingSlipBuilder.AddActivity(
                 ActivityNames.TranscodeAudio,
-                EndpointHelper.BuildExecuteActivityUri(TranscodeDashAudioActivity.ExecuteEndpointName),
+                EndpointHelper.BuildExecuteActivityUri(TranscodeAudioActivity.ExecuteEndpointName),
-                new TranscodeDashAudioArguments(
+                new TranscodeAudioArguments(
                     message.TrackId,
                     RoutingSlipVariableNames.Audio.SourceFilePath,
                     RoutingSlipVariableNames.Workflow.TemporalDirectory));

Infrastructure/Services/AudioTranscoderService.cs

@@ -11,29 +11,29 @@ namespace Musify.Infrastructure.Services
     {
         record FfmpegExecutionResult(int ExitCode, string StandardOutput, string StandardError);
 
-        public async Task<int> TranscodeToDashAsync(Stream audioStream, string destinationPath, CancellationToken cancellationToken)
+        public async Task<int> TranscodeToAudioFileAsync(Stream audioStream, string destinationPath, CancellationToken cancellationToken)
         {
             try
             {
                 Directory.CreateDirectory(destinationPath);
 
-                logger.LogInformation("Starting audio transcoding to DASH for {DestinationPath}", destinationPath);
+                logger.LogInformation("Starting audio transcoding for {DestinationPath}", destinationPath);
 
                 var executionResult = await ExecuteFfmpegWithInputAsync(
-                    BuildDashArguments(destinationPath, audioTranscoderConfiguration.Ffmpeg),
+                    BuildAudioFileArguments(destinationPath, audioTranscoderConfiguration.Ffmpeg),
                     destinationPath,
                     audioStream,
-                    "TranscodeToDash",
+                    "TranscodeToAudioFile",
                     cancellationToken);
 
                 if (executionResult.ExitCode != 0)
                 {
-                    logger.LogError("Audio transcoding to DASH failed with exit code {ExitCode}. Output: {StandardOutput}, Error: {StandardError}",
+                    logger.LogError("Audio transcoding failed with exit code {ExitCode}. Output: {StandardOutput}, Error: {StandardError}",
                         executionResult.ExitCode, executionResult.StandardOutput, executionResult.StandardError);
                 }
                 else
                 {
-                    logger.LogInformation("Audio transcoding to DASH completed for {DestinationPath}", destinationPath);
+                    logger.LogInformation("Audio transcoding completed for {DestinationPath}", destinationPath);
                 }
 
                 return executionResult.ExitCode;
@@ -45,7 +45,7 @@ namespace Musify.Infrastructure.Services
             }
             catch (Exception exception)
             {
-                logger.LogError(exception, "Failed to transcode audio to DASH for {DestinationPath}", destinationPath);
+                logger.LogError(exception, "Failed to transcode audio for {DestinationPath}", destinationPath);
                 throw;
             }
         }
@@ -188,9 +188,9 @@ namespace Musify.Infrastructure.Services
             }
         }
 
-        static string BuildDashArguments(string outputDirectory, FfmpegConfiguration ffmpegConfiguration)
+        static string BuildAudioFileArguments(string outputDirectory, FfmpegConfiguration ffmpegConfiguration)
         {
-            var manifestPath = Path.Combine(outputDirectory, ffmpegConfiguration.ManifestFileName);
+            var outputPath = Path.Combine(outputDirectory, ffmpegConfiguration.OutputFileName);
             var additionalArguments = string.IsNullOrWhiteSpace(ffmpegConfiguration.AdditionalArguments)
                 ? string.Empty
                 : $" {ffmpegConfiguration.AdditionalArguments.Trim()}";
@@ -204,15 +204,9 @@ namespace Musify.Infrastructure.Services
                    $"-ac {ffmpegConfiguration.AudioChannels} " +
                    $"-ar {ffmpegConfiguration.AudioSampleRate} " +
                    $"-profile:a {ffmpegConfiguration.AudioProfile} " +
-                   "-f dash " +
+                   "-movflags +faststart" +
-                   $"-seg_duration {ffmpegConfiguration.SegmentDurationSeconds} " +
-                   "-streaming 1 " +
-                   "-use_template 1 " +
-                   "-use_timeline 0 " +
-                   $"-init_seg_name \"{ffmpegConfiguration.InitSegmentName}\" " +
-                   $"-media_seg_name \"{ffmpegConfiguration.MediaSegmentName}\"" +
                    additionalArguments +
-                   $" \"{manifestPath}\"";
+                   $" \"{outputPath}\"";
         }
 
         static string BuildValidateAudioArguments(string filePath)