Make ffmpeg path configurable, also finds it automatically in current folder. Fixes #1932

core/ffmpeg/ffmpeg.go

@@ -9,34 +9,61 @@ import (
 	"os/exec"
 	"strconv"
 	"strings"
+	"sync"
 
+	"github.com/navidrome/navidrome/conf"
 	"github.com/navidrome/navidrome/log"
 )
 
 type FFmpeg interface {
 	Transcode(ctx context.Context, command, path string, maxBitRate int) (io.ReadCloser, error)
 	ExtractImage(ctx context.Context, path string) (io.ReadCloser, error)
-	// TODO Move scanner ffmpeg probe to here
+	Probe(ctx context.Context, files []string) (string, error)
+	CmdPath() (string, error)
 }
 
 func New() FFmpeg {
 	return &ffmpeg{}
 }
 
-const extractImageCmd = "ffmpeg -i %s -an -vcodec copy -f image2pipe -"
+const (
+	extractImageCmd = "ffmpeg -i %s -an -vcodec copy -f image2pipe -"
+	probeCmd        = "ffmpeg %s -f ffmetadata"
+)
 
 type ffmpeg struct{}
 
 func (e *ffmpeg) Transcode(ctx context.Context, command, path string, maxBitRate int) (io.ReadCloser, error) {
+	if _, err := ffmpegCmd(); err != nil {
+		return nil, err
+	}
 	args := createFFmpegCommand(command, path, maxBitRate)
 	return e.start(ctx, args)
 }
 
 func (e *ffmpeg) ExtractImage(ctx context.Context, path string) (io.ReadCloser, error) {
+	if _, err := ffmpegCmd(); err != nil {
+		return nil, err
+	}
 	args := createFFmpegCommand(extractImageCmd, path, 0)
 	return e.start(ctx, args)
 }
 
+func (e *ffmpeg) Probe(ctx context.Context, files []string) (string, error) {
+	if _, err := ffmpegCmd(); err != nil {
+		return "", err
+	}
+	args := createProbeCommand(probeCmd, files)
+	log.Trace(ctx, "Executing ffmpeg command", "args", args)
+	cmd := exec.CommandContext(ctx, args[0], args[1:]...) // #nosec
+	output, _ := cmd.CombinedOutput()
+	return string(output), nil
+}
+
+func (e *ffmpeg) CmdPath() (string, error) {
+	return ffmpegCmd()
+}
+
 func (e *ffmpeg) start(ctx context.Context, args []string) (io.ReadCloser, error) {
 	log.Trace(ctx, "Executing ffmpeg command", "cmd", args)
 	j := &ffCmd{args: args}
@@ -87,7 +114,7 @@ func (j *ffCmd) wait() {
 
 // Path will always be an absolute path
 func createFFmpegCommand(cmd, path string, maxBitRate int) []string {
-	split := strings.Split(cmd, " ")
+	split := strings.Split(fixCmd(cmd), " ")
 	for i, s := range split {
 		s = strings.ReplaceAll(s, "%s", path)
 		s = strings.ReplaceAll(s, "%b", strconv.Itoa(maxBitRate))
@@ -96,3 +123,59 @@ func createFFmpegCommand(cmd, path string, maxBitRate int) []string {
 
 	return split
 }
+
+func createProbeCommand(cmd string, inputs []string) []string {
+	split := strings.Split(fixCmd(cmd), " ")
+	var args []string
+
+	for _, s := range split {
+		if s == "%s" {
+			for _, inp := range inputs {
+				args = append(args, "-i", inp)
+			}
+		} else {
+			args = append(args, s)
+		}
+	}
+	return args
+}
+
+func fixCmd(cmd string) string {
+	split := strings.Split(cmd, " ")
+	var result []string
+	cmdPath, _ := ffmpegCmd()
+	for _, s := range split {
+		if s == "ffmpeg" || s == "ffmpeg.exe" {
+			result = append(result, cmdPath)
+		} else {
+			result = append(result, s)
+		}
+	}
+	return strings.Join(result, " ")
+}
+
+func ffmpegCmd() (string, error) {
+	ffOnce.Do(func() {
+		if conf.Server.FFmpegPath != "" {
+			ffmpegPath = conf.Server.FFmpegPath
+			ffmpegPath, ffmpegErr = exec.LookPath(ffmpegPath)
+		} else {
+			ffmpegPath, ffmpegErr = exec.LookPath("ffmpeg")
+			if errors.Is(ffmpegErr, exec.ErrDot) {
+				log.Trace("ffmpeg found in current folder '.'")
+				ffmpegPath, ffmpegErr = exec.LookPath("./ffmpeg")
+			}
+		}
+		if ffmpegErr == nil {
+			log.Info("Found ffmpeg", "path", ffmpegPath)
+			return
+		}
+	})
+	return ffmpegPath, ffmpegErr
+}
+
+var (
+	ffOnce     sync.Once
+	ffmpegPath string
+	ffmpegErr  error
+)

core/ffmpeg/ffmpeg_test.go

@@ -16,9 +16,23 @@ func TestFFmpeg(t *testing.T) {
 	RunSpecs(t, "FFmpeg Suite")
 }
 
-var _ = Describe("createFFmpegCommand", func() {
-	It("creates a valid command line", func() {
-		args := createFFmpegCommand("ffmpeg -i %s -b:a %bk mp3 -", "/music library/file.mp3", 123)
-		Expect(args).To(Equal([]string{"ffmpeg", "-i", "/music library/file.mp3", "-b:a", "123k", "mp3", "-"}))
+var _ = Describe("ffmpeg", func() {
+	BeforeEach(func() {
+		_, _ = ffmpegCmd()
+		ffmpegPath = "ffmpeg"
+		ffmpegErr = nil
+	})
+	Describe("createFFmpegCommand", func() {
+		It("creates a valid command line", func() {
+			args := createFFmpegCommand("ffmpeg -i %s -b:a %bk mp3 -", "/music library/file.mp3", 123)
+			Expect(args).To(Equal([]string{"ffmpeg", "-i", "/music library/file.mp3", "-b:a", "123k", "mp3", "-"}))
+		})
+	})
+
+	Describe("createProbeCommand", func() {
+		It("creates a valid command line", func() {
+			args := createProbeCommand(probeCmd, []string{"/music library/one.mp3", "/music library/two.mp3"})
+			Expect(args).To(Equal([]string{"ffmpeg", "-i", "/music library/one.mp3", "-i", "/music library/two.mp3", "-f", "ffmetadata"}))
+		})
 	})
 })