fix(transcoding): include ffprobe in MSI and fall back gracefully when absent (#5326)

* fix(msi): include ffprobe executable in MSI build

Signed-off-by: Deluan <deluan@navidrome.org>

* feat(ffmpeg): add IsProbeAvailable() to FFmpeg interface

Add runtime check for ffprobe binary availability with cached result
and startup logging. When ffprobe is missing, logs a warning at startup.

* feat(stream): guard MakeDecision behind ffprobe availability

When ffprobe is not available, MakeDecision returns a decision with
ErrorReason set and both CanDirectPlay and CanTranscode false, instead
of failing with an opaque exec error.

* feat(subsonic): only advertise transcoding extension when ffprobe is available

The OpenSubsonic transcoding extension is now conditionally included
based on ffprobe availability, so clients know not to call
getTranscodeDecision when ffprobe is missing.

* refactor(ffmpeg): move ffprobe startup warning to initial_setup

Move the ffprobe availability warning from the lazy IsProbeAvailable()
check to checkFFmpegInstallation() in server/initial_setup.go, alongside
the existing ffmpeg warning. This ensures the warning appears at startup
rather than on first endpoint call.

* fix(e2e): set noopFFmpeg.IsProbeAvailable to true

The e2e tests use pre-populated probe data and don't need a real ffprobe
binary. Setting IsProbeAvailable to true allows the transcode decision
logic to proceed normally in e2e tests.

* fix(stream): only guard on ffprobe when probing is needed

Move the IsProbeAvailable() guard inside the SkipProbe check so that
legacy stream requests (which pass SkipProbe: true) are not blocked
when ffprobe is missing. The guard only applies when probing is
actually required (i.e., getTranscodeDecision endpoint).

* refactor(stream): fall back to tag metadata when ffprobe is unavailable

Instead of blocking getTranscodeDecision when ffprobe is missing,
fall back to tag-based metadata (same behavior as /rest/stream).
The transcoding extension is always advertised. A startup warning
still alerts admins when ffprobe is not found.

* fix(stream): downgrade ffprobe-unavailable log to Debug

Avoids log spam when clients call getTranscodeDecision repeatedly
without ffprobe installed. The startup warning in initial_setup.go
already alerts admins at Warn level.

---------

Signed-off-by: Deluan <deluan@navidrome.org>

core/ffmpeg/ffmpeg.go

@@ -49,6 +49,7 @@ type FFmpeg interface {
 	ProbeAudioStream(ctx context.Context, filePath string) (*AudioProbeResult, error)
 	CmdPath() (string, error)
 	IsAvailable() bool
+	IsProbeAvailable() bool
 	Version() string
 }
 
@@ -224,6 +225,19 @@ func (e *ffmpeg) IsAvailable() bool {
 	return err == nil
 }
 
+func (e *ffmpeg) IsProbeAvailable() bool {
+	if _, err := ffmpegCmd(); err != nil {
+		return false
+	}
+	probeOnce.Do(func() {
+		probePath := ffprobePath(ffmpegPath)
+		if _, err := exec.LookPath(probePath); err == nil {
+			probeAvail = true
+		}
+	})
+	return probeAvail
+}
+
 // Version executes ffmpeg -version and extracts the version from the output.
 // Sample output: ffmpeg version 6.0 Copyright (c) 2000-2023 the FFmpeg developers
 func (e *ffmpeg) Version() string {
@@ -533,4 +547,6 @@ var (
 	ffOnce     sync.Once
 	ffmpegPath string
 	ffmpegErr  error
+	probeOnce  sync.Once
+	probeAvail bool
 )

core/stream/decider.go

@@ -44,12 +44,16 @@ func (s *deciderService) MakeDecision(ctx context.Context, mf *model.MediaFile,
 
 	var probe *ffmpeg.AudioProbeResult
 	if !opts.SkipProbe {
+		if !s.ff.IsProbeAvailable() {
+			log.Debug(ctx, "ffprobe not available, using tag metadata for transcode decision", "mediaID", mf.ID)
+		} else {
 			var err error
 			probe, err = s.ensureProbed(ctx, mf)
 			if err != nil {
 				return nil, err
 			}
 		}
+	}
 
 	// Build source stream details (uses probe data if available)
 	decision.SourceStream = buildSourceStream(mf, probe)

core/stream/decider_test.go

@@ -1164,6 +1164,7 @@ var _ = Describe("Decider", func() {
 				Expect(bitrate).To(Equal(fallbackBitrate))
 			})
 		})
+
 	})
 
 	Describe("ensureProbed", func() {

release/wix/build_msi.sh

@@ -43,8 +43,9 @@ FFMPEG_FILE="ffmpeg-n${FFMPEG_VERSION}-latest-${WIN_ARCH}-gpl-${FFMPEG_VERSION}"
 wget --quiet --output-document="${DOWNLOAD_FOLDER}/ffmpeg.zip" \
   "https://github.com/${FFMPEG_REPOSITORY}/releases/download/latest/${FFMPEG_FILE}.zip"
 rm -rf "${DOWNLOAD_FOLDER}/extracted_ffmpeg"
-unzip -d "${DOWNLOAD_FOLDER}/extracted_ffmpeg" "${DOWNLOAD_FOLDER}/ffmpeg.zip" "*/ffmpeg.exe"
+unzip -d "${DOWNLOAD_FOLDER}/extracted_ffmpeg" "${DOWNLOAD_FOLDER}/ffmpeg.zip" "*/ffmpeg.exe" "*/ffprobe.exe"
 cp "${DOWNLOAD_FOLDER}"/extracted_ffmpeg/${FFMPEG_FILE}/bin/ffmpeg.exe "$MSI_OUTPUT_DIR"
+cp "${DOWNLOAD_FOLDER}"/extracted_ffmpeg/${FFMPEG_FILE}/bin/ffprobe.exe "$MSI_OUTPUT_DIR"
 
 cp "$WORKSPACE"/LICENSE "$WORKSPACE"/README.md "$MSI_OUTPUT_DIR"
 cp "$BINARY" "$MSI_OUTPUT_DIR"

release/wix/navidrome.wxs

@@ -67,6 +67,10 @@
 						<File Id='ffmpeg.exe' Name='ffmpeg.exe' DiskId='1' Source='ffmpeg.exe' KeyPath='yes' />
 					</Component>
 
+					<Component Id='FFProbeExecutable' Guid='f8a3b2c1-5d4e-4f6a-9b8c-7e2d1a0f3c5b' Win64="$(var.Win64)">
+						<File Id='ffprobe.exe' Name='ffprobe.exe' DiskId='1' Source='ffprobe.exe' KeyPath='yes' />
+					</Component>
+
 				</Directory>
 			</Directory>
 
@@ -87,6 +91,7 @@
 			<ComponentRef Id='Configuration'/>
 			<ComponentRef Id='MainExecutable' />
 			<ComponentRef Id='FFMpegExecutable' />
+			<ComponentRef Id='FFProbeExecutable' />
 			<ComponentRef Id='PackageFile' />
 		</Feature>
 	</Product>

server/e2e/e2e_suite_test.go

@@ -337,6 +337,7 @@ func (n noopFFmpeg) ConvertAnimatedImage(context.Context, io.Reader, int, int) (
 
 func (n noopFFmpeg) CmdPath() (string, error) { return "", nil }
 func (n noopFFmpeg) IsAvailable() bool        { return false }
+func (n noopFFmpeg) IsProbeAvailable() bool   { return true }
 func (n noopFFmpeg) Version() string          { return "noop" }
 
 // noopArchiver implements core.Archiver

server/initial_setup.go

@@ -68,14 +68,17 @@ func createInitialAdminUser(ds model.DataStore, initialPassword string) error {
 func checkFFmpegInstallation() {
 	f := ffmpeg.New()
 	_, err := f.CmdPath()
-	if err == nil {
-		return
-	}
+	if err != nil {
 		log.Warn("Unable to find ffmpeg. Transcoding will fail if used", err)
 		if conf.Server.Scanner.Extractor == "ffmpeg" {
 			log.Warn("ffmpeg cannot be used for metadata extraction. Falling back to taglib")
 			conf.Server.Scanner.Extractor = "taglib"
 		}
+		return
+	}
+	if !f.IsProbeAvailable() {
+		log.Warn("Unable to find ffprobe. Transcoding decisions will be limited")
+	}
 }
 
 func checkExternalCredentials() {

tests/mock_ffmpeg.go

@@ -12,7 +12,7 @@ import (
 )
 
 func NewMockFFmpeg(data string) *MockFFmpeg {
-	return &MockFFmpeg{Reader: strings.NewReader(data)}
+	return &MockFFmpeg{Reader: strings.NewReader(data), ProbeAvailable: true}
 }
 
 type MockFFmpeg struct {
@@ -21,12 +21,17 @@ type MockFFmpeg struct {
 	closed           atomic.Bool
 	Error            error
 	ProbeAudioResult *ffmpeg.AudioProbeResult
+	ProbeAvailable   bool
 }
 
 func (ff *MockFFmpeg) IsAvailable() bool {
 	return true
 }
 
+func (ff *MockFFmpeg) IsProbeAvailable() bool {
+	return ff.ProbeAvailable
+}
+
 func (ff *MockFFmpeg) Transcode(_ context.Context, _ ffmpeg.TranscodeOptions) (io.ReadCloser, error) {
 	if ff.Error != nil {
 		return nil, ff.Error