Support video-only streams if there is no audio in the inbound stream. (#401)

Closes #400

core/rtmp/broadcaster.go

@@ -27,6 +27,7 @@ func setCurrentBroadcasterInfo(t flvio.Tag, remoteAddr string) {
 			AudioBitrate:   int(data.AudioBitrate),
 			AudioCodec:     getAudioCodec(data.AudioCodec),
 			Encoder:        data.Encoder,
+			VideoOnly:      data.AudioCodec == nil,
 		},
 	}
 

core/rtmp/rtmp.go

@@ -70,6 +70,7 @@ func HandleConn(c *rtmp.Conn, nc net.Conn) {
 		if t.Type == flvio.TAG_AMF0 {
 			log.Tracef("%+v\n", t.DebugFields())
 			setCurrentBroadcasterInfo(t, nc.RemoteAddr().String())
+			_setStreamAsConnected()
 		}
 	}
 
@@ -98,7 +99,6 @@ func HandleConn(c *rtmp.Conn, nc net.Conn) {
 	}
 
 	_hasInboundRTMPConnection = true
-	_setStreamAsConnected()
 	_rtmpConnection = nc
 
 	f, err := os.OpenFile(pipePath, os.O_RDWR, os.ModeNamedPipe)

core/rtmp/utils.go

@@ -30,6 +30,10 @@ func getInboundDetailsFromMetadata(metadata []interface{}) (models.RTMPStreamMet
 }
 
 func getAudioCodec(codec interface{}) string {
+	if codec == nil {
+		return "No audio"
+	}
+
 	var codecID float64
 	if assertedCodecID, ok := codec.(float64); ok {
 		codecID = assertedCodecID