Use custom stream to record audio

src/Drastic.AudioRecorder/AudioRecorderService.cs

@@ -22,6 +22,7 @@ public partial class AudioRecorderService
     private DateTime? silenceTime;
     private DateTime? startTime;
     private TaskCompletionSource<string> recordTask;
+    FileStream fileStream;
 
     /// <summary>
     /// Initializes a new instance of the <see cref="AudioRecorderService"/> class.
@@ -92,24 +93,37 @@ public AudioRecorderService()
     /// <remarks>Defaults to .15.  Value should be between 0 and 1.</remarks>
     public float SilenceThreshold { get; set; } = .15f;
 
+    /// <summary>
+    /// Gets/sets a value indicating if headers will be written to the file/stream.
+    /// </summary>
+    /// <remarks>Defaults to <c>true</c></remarks>
+    public bool WriteHeaders { get; set; } = true;
+
     /// <summary>
     /// Starts recording audio.
     /// </summary>
+    /// <param name="recordStream"><c>null</c> (default) Optional stream to write audio data to, if null, a file will be created.</param>
     /// <returns>A <see cref="Task"/> that will complete when recording is finished.
     /// The task result will be the path to the recorded audio file, or null if no audio was recorded.</returns>
-    public async Task<Task<string>> StartRecording()
+    public async Task<Task<string>> StartRecording(Stream recordStream = null)
     {
-        if (this.FilePath == null)
+        if (recordStream == null)
         {
-            this.FilePath = await this.GetDefaultFilePath();
+            if (this.FilePath == null)
+            {
+                this.FilePath = await this.GetDefaultFilePath();
+            }
+
+            fileStream = new FileStream(FilePath, FileMode.Create, FileAccess.Write, FileShare.Read);
+            recordStream = fileStream;
         }
 
         this.ResetAudioDetection();
         this.OnRecordingStarting();
 
         this.InitializeStream(this.PreferredSampleRate);
 
-        await this.recorder.StartRecorder(this.audioStream, this.FilePath);
+        await this.recorder.StartRecorder(this.audioStream, recordStream, WriteHeaders);
 
         this.AudioStreamDetails = new AudioStreamDetails
         {
@@ -134,7 +148,8 @@ public async Task<Task<string>> StartRecording()
     /// <returns>A <see cref="Stream"/> object that can be used to read the audio file from the beginning.</returns>
     public Stream GetAudioFileStream()
     {
-        return this.recorder.GetAudioFileStream();
+        //return a new stream to the same audio file, in Read mode
+        return new FileStream(FilePath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
     }
 
     /// <summary>
@@ -159,11 +174,12 @@ public async Task StopRecording(bool continueProcessing = true)
             Debug.WriteLine("Error in StopRecording: {0}", ex);
         }
 
+        fileStream?.Dispose();
         this.OnRecordingStopped();
 
         var returnedFilePath = this.GetAudioFilePath();
 
-        // complete the recording Task for anthing waiting on this
+        // complete the recording Task for anything waiting on this
         this.recordTask.TrySetResult(returnedFilePath);
 
         if (continueProcessing)

src/Drastic.AudioRecorder/WaveRecorder.cs

@@ -9,26 +9,33 @@ namespace Drastic.AudioRecorder;
 
 internal class WaveRecorder : IDisposable
 {
-    private string audioFilePath;
-    private FileStream fileStream;
-    private StreamWriter streamWriter;
     private BinaryWriter writer;
     private int byteCount;
     private IAudioStream audioStream;
+    bool writeHeadersToStream;
 
     /// <summary>
     /// Starts recording WAVE format audio from the audio stream.
     /// </summary>
     /// <param name="stream">A <see cref="IAudioStream"/> that provides the audio data.</param>
+    /// <param name="recordStream">The stream the audio will be written to.</param>
     /// <param name="filePath">The full path of the file to record audio to.</param>
+    /// <param name="writeHeaders"><c>false</c> (default) Write WAV headers to stream at the end of recording.</param>
     /// <returns>A <see cref="Task"/> representing the asynchronous operation.</returns>
-    public async Task StartRecorder(IAudioStream stream, string filePath)
+    public async Task StartRecorder(IAudioStream stream, Stream recordStream, bool writeHeaders = false)
     {
         if (stream == null)
         {
             throw new ArgumentNullException(nameof(stream));
         }
 
+        if (recordStream == null)
+        {
+            throw new ArgumentNullException(nameof(recordStream));
+        }
+
+        writeHeadersToStream = writeHeaders;
+
         try
         {
             // if we're restarting, let's see if we have an existing stream configured that can be stopped
@@ -37,12 +44,8 @@ public async Task StartRecorder(IAudioStream stream, string filePath)
                 await this.audioStream.Stop();
             }
 
-            this.audioFilePath = filePath;
             this.audioStream = stream;
-
-            this.fileStream = new FileStream(filePath, FileMode.Create, FileAccess.Write, FileShare.Read);
-            this.streamWriter = new StreamWriter(this.fileStream);
-            this.writer = new BinaryWriter(this.streamWriter.BaseStream, Encoding.UTF8);
+            this.writer = new BinaryWriter(recordStream, Encoding.UTF8);
 
             this.byteCount = 0;
             this.audioStream.OnBroadcast += this.OnStreamBroadcast;
@@ -62,16 +65,6 @@ public async Task StartRecorder(IAudioStream stream, string filePath)
         }
     }
 
-    /// <summary>
-    /// Gets a new <see cref="Stream"/> to the audio file in readonly mode.
-    /// </summary>
-    /// <returns>A <see cref="Stream"/> object that can be used to read the audio file from the beginning.</returns>
-    public Stream GetAudioFileStream()
-    {
-        // return a new stream to the same audio file, in Read mode
-        return new FileStream(this.audioFilePath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
-    }
-
     /// <summary>
     /// Stops recording WAV audio from the underlying <see cref="IAudioStream"/> and finishes writing the WAV file.
     /// </summary>
@@ -87,7 +80,7 @@ public void StopRecorder()
 
             if (this.writer != null)
             {
-                if (this.streamWriter.BaseStream.CanWrite)
+                if (writeHeadersToStream && this.writer.BaseStream.CanWrite && this.writer.BaseStream.CanSeek)
                 {
                     // now that audio is finished recording, write a WAV/RIFF header at the beginning of the file
                     this.writer.Seek(0, SeekOrigin.Begin);
@@ -96,8 +89,6 @@ public void StopRecorder()
 
                 this.writer.Dispose(); // this should properly close/dispose the underlying stream as well
                 this.writer = null;
-                this.fileStream = null;
-                this.streamWriter = null;
             }
 
             this.audioStream = null;
@@ -127,7 +118,7 @@ private void OnStreamBroadcast(object sender, byte[] bytes)
     {
         try
         {
-            if (this.writer != null && this.streamWriter != null)
+            if (this.writer != null)
             {
                 this.writer.Write(bytes);
                 this.byteCount += bytes.Length;