Response with error on codec negotiation

cmd/streams/producer.go

@@ -24,6 +24,7 @@ type Producer struct {
 	template string
 
 	element streamer.Producer
+	lastErr error
 	tracks  []*streamer.Track
 
 	state   state
@@ -45,10 +46,9 @@ func (p *Producer) GetMedias() []*streamer.Media {
 	if p.state == stateNone {
 		log.Debug().Msgf("[streams] probe producer url=%s", p.url)
 
-		var err error
-		p.element, err = GetProducer(p.url)
-		if err != nil || p.element == nil {
-			log.Error().Err(err).Caller().Send()
+		p.element, p.lastErr = GetProducer(p.url)
+		if p.lastErr != nil || p.element == nil {
+			log.Error().Err(p.lastErr).Caller().Send()
 			return nil
 		}
 

cmd/streams/stream.go

@@ -99,11 +99,18 @@ func (s *Stream) AddConsumer(cons streamer.Consumer) (err error) {
 
 	if len(producers) == 0 {
 		s.stopProducers()
+
 		if len(codecs) > 0 {
 			return errors.New("codecs not match: " + codecs)
-		} else {
-			return fmt.Errorf("sources unavailable: %d", len(s.producers))
 		}
+
+		for i, producer := range s.producers {
+			if producer.lastErr != nil {
+				return fmt.Errorf("source %d error: %w", i, producer.lastErr)
+			}
+		}
+
+		return fmt.Errorf("sources unavailable: %d", len(s.producers))
 	}
 
 	s.mu.Lock()