Method AddConsumer

jsm.go:447–472

AddConsumer adds a consumer to a stream. If the consumer already exists, and the configuration is the same, it will return the existing consumer. If the consumer already exists, and the configuration is different, it will return ErrConsumerNameAlreadyInUse.

(stream string, cfg *ConsumerConfig, opts ...JSOpt)

// If the consumer already exists, and the configuration is different, it
// will return ErrConsumerNameAlreadyInUse.
func (js *js) AddConsumer(stream string, cfg *ConsumerConfig, opts ...JSOpt) (*ConsumerInfo, error) {
	if cfg == nil {
		cfg = &ConsumerConfig{}
	}
	consumerName := cfg.Name
	if consumerName == _EMPTY_ {
		consumerName = cfg.Durable
	}
	if consumerName != _EMPTY_ {
		consInfo, err := js.ConsumerInfo(stream, consumerName, opts...)
		if err != nil && !errors.Is(err, ErrConsumerNotFound) && !errors.Is(err, ErrStreamNotFound) {
			return nil, err
		}

		if consInfo != nil {
			sameConfig := checkConfig(&consInfo.Config, cfg)
			if sameConfig != nil {
				return nil, fmt.Errorf("%w: creating consumer %q on stream %q", ErrConsumerNameAlreadyInUse, consumerName, stream)
			} else {
				return consInfo, nil
			}
		}
	}

	return js.upsertConsumer(stream, consumerName, cfg, opts...)
}

func (js *js) UpdateConsumer(stream string, cfg *ConsumerConfig, opts ...JSOpt) (*ConsumerInfo, error) {
	if cfg == nil {