internal/adapters/audio/ffmpeg_test.go

@@ -109,3 +109,20 @@ printf data > "$last"`)
 	require.NoError(t, err)
 	assert.NotContains(t, " "+strings.ReplaceAll(string(raw), "\n", " ")+" ", " -t ")
 }
+
+func TestFFmpegToWAV_CapsTheStreamCountBeforeTheInput(t *testing.T) {
+	// ffmpeg also allocated ~570 MB opening the 900-stream file (#49).
+	rec := filepath.Join(t.TempDir(), "argv")
+	bin := stub(t, `printf '%s\n' "$@" > `+rec+`
+for a; do last="$a"; done
+printf data > "$last"`)
+
+	err := (&audio.FFmpeg{Bin: bin}).ToWAV(context.Background(), "/spool/in", filepath.Join(t.TempDir(), "o.wav"))
+
+	require.NoError(t, err)
+	args := argvOf(t, rec)
+	ms, in := indexOf(args, "-max_streams"), indexOf(args, "-i")
+	require.GreaterOrEqual(t, ms, 0, "argv: %v", args)
+	assert.Equal(t, "32", args[ms+1])
+	assert.Less(t, ms, in, "an input option placed after -i is applied to the output")
+}

internal/adapters/audio/ffprobe_test.go

@@ -184,3 +184,34 @@ func TestAllowedDemuxers_ExcludeThePlaylistFormats(t *testing.T) {
 		assert.Contains(t, strings.Split(audio.AllowedDemuxers, ","), good)
 	}
 }
+
+func TestFFprobeProbe_CapsTheStreamCountBeforeTheInput(t *testing.T) {
+	// A 1.3 MB file declaring 900 streams cost ~570 MB of RSS in ffprobe (#49) against
+	// a 512 Mi pod. -max_streams is an input option: it must precede the path.
+	bin, argvFile := argvStub(t)
+
+	_, err := (&audio.FFprobe{Bin: bin}).Probe(context.Background(), "/spool/upload-1")
+
+	require.NoError(t, err)
+	args := argvOf(t, argvFile)
+	ms := indexOf(args, "-max_streams")
+	require.GreaterOrEqual(t, ms, 0, "argv: %v", args)
+	assert.Equal(t, "32", args[ms+1])
+	assert.Less(t, ms, len(args)-1, "must come before the path, which stays last")
+}
+
+func TestFFprobeProbe_AsksOnlyForTheFieldsParseProbeReads(t *testing.T) {
+	// -show_format/-show_streams print every tag: a 120 MB WAV produced 491 MB of JSON
+	// that cmd.Output() buffers in Go (#49).
+	bin, argvFile := argvStub(t)
+
+	_, err := (&audio.FFprobe{Bin: bin}).Probe(context.Background(), "/spool/upload-1")
+
+	require.NoError(t, err)
+	args := argvOf(t, argvFile)
+	assert.Equal(t, -1, indexOf(args, "-show_format"), "argv: %v", args)
+	assert.Equal(t, -1, indexOf(args, "-show_streams"), "argv: %v", args)
+	se := indexOf(args, "-show_entries")
+	require.GreaterOrEqual(t, se, 0, "argv: %v", args)
+	assert.Equal(t, "format=duration:stream=codec_type:stream_disposition=attached_pic", args[se+1])
+}