Make video segment filename unique (#214)

* Make video segment filename unique

* fix typo

* Remove type casting function

core/ffmpeg/transcoder.go

@@ -8,6 +8,7 @@ import (
 	"strings"
 
 	log "github.com/sirupsen/logrus"
+	"github.com/teris-io/shortid"
 
 	"github.com/gabek/owncast/config"
 	"github.com/gabek/owncast/utils"
@@ -25,6 +26,7 @@ type Transcoder struct {
 	segmentLengthSeconds int
 	appendToStream       bool
 	ffmpegPath           string
+	segmentIdentifier    string
 }
 
 // HLSVariant is a combination of settings that results in a single HLS stream
@@ -103,6 +105,10 @@ func (t *Transcoder) getString() string {
 		hlsOptionFlags = append(hlsOptionFlags, "append_list")
 	}
 
+	if t.segmentIdentifier == "" {
+		t.segmentIdentifier = shortid.MustGenerate()
+	}
+
 	ffmpegFlags := []string{
 		"cat", t.input, "|",
 		t.ffmpegPath,
@@ -125,7 +131,7 @@ func (t *Transcoder) getString() string {
 		// Filenames
 		"-master_pl_name", "stream.m3u8",
 		"-strftime 1",                                                               // Support the use of strftime in filenames
-		"-hls_segment_filename", path.Join(t.segmentOutputPath, "/%v/stream-%s.ts"), // Each segment's filename
+		"-hls_segment_filename", path.Join(t.segmentOutputPath, "/%v/stream-%s-"+t.segmentIdentifier+".ts"), // Each segment's filename
 		"-max_muxing_queue_size", "400", // Workaround for Too many packets error: https://trac.ffmpeg.org/ticket/6375?cversion=0
 		path.Join(t.segmentOutputPath, "/%v/stream.m3u8"), // Each variant's playlist
 		"2> transcoder.log",
@@ -353,3 +359,8 @@ func (t *Transcoder) SetSegmentLength(seconds int) {
 func (t *Transcoder) SetAppendToStream(append bool) {
 	t.appendToStream = append
 }
+
+// SetIdentifer enables appending a unique identifier to segment file name
+func (t *Transcoder) SetIdentifier(output string) {
+	t.segmentIdentifier = output
+}

core/ffmpeg/transcoder_test.go

@@ -11,6 +11,7 @@ func TestFFmpegCommand(t *testing.T) {
 	transcoder.SetInput("fakecontent.flv")
 	transcoder.SetOutputPath("fakeOutput")
 	transcoder.SetHLSPlaylistLength(10)
+	transcoder.SetIdentifier("jdofFGg")
 
 	variant := HLSVariant{}
 	variant.videoBitrate = 1200
@@ -22,7 +23,7 @@ func TestFFmpegCommand(t *testing.T) {
 
 	cmd := transcoder.getString()
 
-	expected := `cat fakecontent.flv | /fake/path/ffmpeg -hide_banner -i pipe:  -map v:0 -c:v:0 libx264 -b:v:0 1200k -maxrate:v:0 1272k -bufsize:v:0 1440k -g:v:0 119 -x264-params:v:0 "scenecut=0:open_gop=0:min-keyint=119:keyint=119" -map a:0 -c:a:0 copy -r 30 -preset veryfast  -var_stream_map "v:0,a:0 " -f hls -hls_time 4 -hls_list_size 10 -hls_delete_threshold 10 -hls_flags delete_segments+program_date_time+temp_file -tune zerolatency -sc_threshold 0 -master_pl_name stream.m3u8 -strftime 1 -hls_segment_filename fakeOutput/%v/stream-%s.ts -max_muxing_queue_size 400 fakeOutput/%v/stream.m3u8 2> transcoder.log`
+	expected := `cat fakecontent.flv | /fake/path/ffmpeg -hide_banner -i pipe:  -map v:0 -c:v:0 libx264 -b:v:0 1200k -maxrate:v:0 1272k -bufsize:v:0 1440k -g:v:0 119 -x264-params:v:0 "scenecut=0:open_gop=0:min-keyint=119:keyint=119" -map a:0 -c:a:0 copy -r 30 -preset veryfast  -var_stream_map "v:0,a:0 " -f hls -hls_time 4 -hls_list_size 10 -hls_delete_threshold 10 -hls_flags delete_segments+program_date_time+temp_file -tune zerolatency -sc_threshold 0 -master_pl_name stream.m3u8 -strftime 1 -hls_segment_filename fakeOutput/%v/stream-%s-jdofFGg.ts -max_muxing_queue_size 400 fakeOutput/%v/stream.m3u8 2> transcoder.log`
 
 	if cmd != expected {
 		t.Errorf("ffmpeg command does not match expected.  Got %s, want: %s", cmd, expected)