feat(meta): write album art & metadata into destination file

algo/qmc/qmc.go

@@ -37,7 +37,7 @@ type Decoder struct {
 	meta          common.AudioMeta
 	cover         []byte
 	embeddedCover bool          // embeddedCover is true if the cover is embedded in the file
-	probeBuf      *bytes.Buffer // probeBuf is the buffer for sniffing metadata
+	probeBuf      *bytes.Buffer // probeBuf is the buffer for sniffing metadata, TODO: consider pipe?
 
 	// provider
 	logger *zap.Logger

cmd/um/main.go

@@ -25,8 +25,10 @@ import (
 	_ "unlock-music.dev/cli/algo/tm"
 	_ "unlock-music.dev/cli/algo/xiami"
 	_ "unlock-music.dev/cli/algo/ximalaya"
+	"unlock-music.dev/cli/internal/ffmpeg"
 	"unlock-music.dev/cli/internal/logging"
 	"unlock-music.dev/cli/internal/sniff"
+	"unlock-music.dev/cli/internal/utils"
 )
 
 var AppVersion = "v0.0.6"
@@ -187,60 +189,80 @@ func tryDecFile(inputFile string, outputDir string, allDec []common.NewDecoderFu
 		return errors.New("no any decoder can resolve the file")
 	}
 
+	params := &ffmpeg.UpdateMetadataParams{}
+
 	header := bytes.NewBuffer(nil)
 	_, err = io.CopyN(header, dec, 64)
 	if err != nil {
 		return fmt.Errorf("read header failed: %w", err)
 	}
+	audio := io.MultiReader(header, dec)
+	params.AudioExt = sniff.AudioExtensionWithFallback(header.Bytes(), ".mp3")
 
-	outExt := sniff.AudioExtensionWithFallback(header.Bytes(), ".mp3")
+	if audioMetaGetter, ok := dec.(common.AudioMetaGetter); ok {
-	inFilename := strings.TrimSuffix(filepath.Base(inputFile), filepath.Ext(inputFile))
+		ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+		defer cancel()
 
-	outPath := filepath.Join(outputDir, inFilename+outExt)
+		// since ffmpeg doesn't support multiple input streams,
-	outFile, err := os.OpenFile(outPath, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, 0644)
+		// we need to write the audio to a temp file.
+		// since qmc decoder doesn't support seeking & relying on ffmpeg probe, we need to read the whole file.
+		// TODO: support seeking or using pipe for qmc decoder.
+		params.Audio, err = utils.WriteTempFile(audio, params.AudioExt)
 		if err != nil {
-		return err
+			return fmt.Errorf("updateAudioMeta write temp file: %w", err)
 		}
-	defer outFile.Close()
+		defer os.Remove(params.Audio)
 
-	if _, err := io.Copy(outFile, header); err != nil {
+		params.Meta, err = audioMetaGetter.GetAudioMeta(ctx)
-		return err
+		if err != nil {
-	}
+			logger.Warn("get audio meta failed", zap.Error(err))
-	if _, err := io.Copy(outFile, dec); err != nil {
-		return err
 		}
 
-	if audioMetaGetter, ok := dec.(common.AudioMetaGetter); ok {
+		if params.Meta == nil { // reset audio meta if failed
-		ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+			audio, err = os.Open(params.Audio)
-		defer cancel()
-
-		meta, err := audioMetaGetter.GetAudioMeta(ctx)
 			if err != nil {
-			logger.Warn("get audio meta failed", zap.Error(err))
+				return fmt.Errorf("updateAudioMeta open temp file: %w", err)
-		} else {
+			}
-			logger.Info("audio metadata",
-				zap.String("title", meta.GetTitle()),
-				zap.Strings("artists", meta.GetArtists()),
-				zap.String("album", meta.GetAlbum()),
-			)
 		}
 	}
 
+	if params.Meta != nil {
 		if coverGetter, ok := dec.(common.CoverImageGetter); ok {
 			ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
 			defer cancel()
 
-		cover, err := coverGetter.GetCoverImage(ctx)
+			if cover, err := coverGetter.GetCoverImage(ctx); err != nil {
-		if err != nil {
 				logger.Warn("get cover image failed", zap.Error(err))
 			} else if imgExt, ok := sniff.ImageExtension(cover); !ok {
 				logger.Warn("sniff cover image type failed", zap.Error(err))
 			} else {
-			coverPath := filepath.Join(outputDir, inFilename+imgExt)
+				params.AlbumArtExt = imgExt
-			err = os.WriteFile(coverPath, cover, 0644)
+				params.AlbumArt = bytes.NewReader(cover)
+			}
+		}
+	}
+
+	inFilename := strings.TrimSuffix(filepath.Base(inputFile), filepath.Ext(inputFile))
+	outPath := filepath.Join(outputDir, inFilename+params.AudioExt)
+
+	if params.Meta == nil {
+		outFile, err := os.OpenFile(outPath, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, 0644)
 		if err != nil {
-				logger.Warn("write cover image failed", zap.Error(err))
+			return err
 		}
+		defer outFile.Close()
+
+		if _, err = io.Copy(outFile, audio); err != nil {
+			return err
+		}
+		outFile.Close()
+
+	} else {
+		ctx, cancel := context.WithTimeout(context.Background(), time.Minute)
+		defer cancel()
+
+		if err := ffmpeg.UpdateAudioMetadata(ctx, outPath, params); err != nil {
+			return err
 		}
 	}
 

internal/ffmpeg/ffmpeg.go

@@ -10,6 +10,7 @@ import (
 	"strings"
 
 	"unlock-music.dev/cli/algo/common"
+	"unlock-music.dev/cli/internal/utils"
 )
 
 func ExtractAlbumArt(ctx context.Context, rd io.Reader) (*bytes.Buffer, error) {
@@ -33,7 +34,7 @@ func ExtractAlbumArt(ctx context.Context, rd io.Reader) (*bytes.Buffer, error) {
 }
 
 type UpdateMetadataParams struct {
-	Audio    io.Reader // required
+	Audio    string // required
 	AudioExt string // required
 
 	Meta common.AudioMeta // required
@@ -42,24 +43,15 @@ type UpdateMetadataParams struct {
 	AlbumArtExt string    // required if AlbumArt is not nil
 }
 
-func UpdateAudioMetadata(ctx context.Context, params *UpdateMetadataParams) (*bytes.Buffer, error) {
+func UpdateAudioMetadata(ctx context.Context, outPath string, params *UpdateMetadataParams) error {
 	builder := newFFmpegBuilder()
-	builder.SetFlag("y") // overwrite output file
 
-	out := newOutputBuilder("pipe:1")                        // use stdout as output
+	out := newOutputBuilder(outPath) // output to file
-	out.AddOption("f", encodeFormatFromExt(params.AudioExt)) // use mp3 muxer
+	builder.SetFlag("y")             // overwrite output file
 	builder.AddOutput(out)
 
-	// since ffmpeg doesn't support multiple input streams,
-	// we need to write the audio to a temp file
-	audioPath, err := writeTempFile(params.Audio, params.AudioExt)
-	if err != nil {
-		return nil, fmt.Errorf("updateAudioMeta write temp file: %w", err)
-	}
-	defer os.Remove(audioPath)
-
 	// input audio -> output audio
-	builder.AddInput(newInputBuilder(audioPath)) // input 0: audio
+	builder.AddInput(newInputBuilder(params.Audio)) // input 0: audio
 	out.AddOption("map", "0:a")
 	out.AddOption("codec:a", "copy")
 
@@ -68,9 +60,9 @@ func UpdateAudioMetadata(ctx context.Context, params *UpdateMetadataParams) (*by
 		params.AudioExt != ".wav" /* wav doesn't support attached image */ {
 
 		// write cover to temp file
-		artPath, err := writeTempFile(params.AlbumArt, params.AlbumArtExt)
+		artPath, err := utils.WriteTempFile(params.AlbumArt, params.AlbumArtExt)
 		if err != nil {
-			return nil, fmt.Errorf("updateAudioMeta write temp file: %w", err)
+			return fmt.Errorf("updateAudioMeta write temp file: %w", err)
 		}
 		defer os.Remove(artPath)
 
@@ -108,51 +100,10 @@ func UpdateAudioMetadata(ctx context.Context, params *UpdateMetadataParams) (*by
 
 	// execute ffmpeg
 	cmd := builder.Command(ctx)
-	stdout, stderr := &bytes.Buffer{}, &bytes.Buffer{}
-	cmd.Stdout, cmd.Stderr = stdout, stderr
-
-	if err := cmd.Run(); err != nil {
-		return nil, fmt.Errorf("ffmpeg run: %w", err)
-	}
 
-	return stdout, nil
+	if stdout, err := cmd.CombinedOutput(); err != nil {
-}
+		return fmt.Errorf("ffmpeg run: %w, %s", err, string(stdout))
-
-func writeTempFile(rd io.Reader, ext string) (string, error) {
-	audioFile, err := os.CreateTemp("", "*"+ext)
-	if err != nil {
-		return "", fmt.Errorf("ffmpeg create temp file: %w", err)
-	}
-
-	if _, err := io.Copy(audioFile, rd); err != nil {
-		return "", fmt.Errorf("ffmpeg write temp file: %w", err)
 	}
 
-	if err := audioFile.Close(); err != nil {
+	return nil
-		return "", fmt.Errorf("ffmpeg close temp file: %w", err)
-	}
-
-	return audioFile.Name(), nil
-}
-
-// encodeFormatFromExt returns the file format name the recognized & supporting encoding by ffmpeg.
-func encodeFormatFromExt(ext string) string {
-	switch ext {
-	case ".flac":
-		return "flac" // raw FLAC
-	case ".mp3":
-		return "mp3" // MP3 (MPEG audio layer 3)
-	case ".ogg":
-		return "ogg" // Ogg
-	case ".m4a":
-		return "ipod" // iPod H.264 MP4 (MPEG-4 Part 14)
-	case ".wav":
-		return "wav" // WAV / WAVE (Waveform Audio)
-	case ".aac":
-		return "adts" // ADTS AAC (Advanced Audio Coding)
-	case ".wma":
-		return "asf" // ASF (Advanced / Active Streaming Format)
-	default:
-		return ""
-	}
 }

internal/ffmpeg/ffprobe.go

@@ -1,6 +1,7 @@
 package ffmpeg
 
 import (
+	"bytes"
 	"context"
 	"encoding/json"
 	"io"
@@ -119,17 +120,20 @@ func ProbeReader(ctx context.Context, rd io.Reader) (*Result, error) {
 	cmd := exec.CommandContext(ctx, "ffprobe",
 		"-v", "quiet", // disable logging
 		"-print_format", "json", // use json format
-		"-show_format", "-show_streams", // retrieve format and streams
+		"-show_format", "-show_streams", "-show_error", // retrieve format and streams
-		"-", // input from stdin
+		"pipe:0", // input from stdin
 	)
+
 	cmd.Stdin = rd
-	out, err := cmd.Output()
+	stdout, stderr := &bytes.Buffer{}, &bytes.Buffer{}
-	if err != nil {
+	cmd.Stdout, cmd.Stderr = stdout, stderr
+
+	if err := cmd.Run(); err != nil {
 		return nil, err
 	}
 
 	ret := new(Result)
-	if err := json.Unmarshal(out, ret); err != nil {
+	if err := json.Unmarshal(stdout.Bytes(), ret); err != nil {
 		return nil, err
 	}
 

internal/utils/temp.go

@@ -0,0 +1,24 @@
+package utils
+
+import (
+	"fmt"
+	"io"
+	"os"
+)
+
+func WriteTempFile(rd io.Reader, ext string) (string, error) {
+	audioFile, err := os.CreateTemp("", "*"+ext)
+	if err != nil {
+		return "", fmt.Errorf("ffmpeg create temp file: %w", err)
+	}
+
+	if _, err := io.Copy(audioFile, rd); err != nil {
+		return "", fmt.Errorf("ffmpeg write temp file: %w", err)
+	}
+
+	if err := audioFile.Close(); err != nil {
+		return "", fmt.Errorf("ffmpeg close temp file: %w", err)
+	}
+
+	return audioFile.Name(), nil
+}