Improved logging

internal/mqtt/mqtt.go

@@ -50,6 +50,7 @@ func NewClient(logger *zap.Logger, config *config.Config, csvHelper *csv.Helper)
 }
 
 func StartListening(logger *zap.Logger, config *config.Config, client mqtt.Client) {
+	logger.Info("Subscribing to", zap.Int("topics", len(config.Topics)))
 	for _, topic := range config.Topics {
 		if token := client.Subscribe(topic, 0, nil); token.Wait() && token.Error() != nil {
 			logger.Error("error subscribing to topic", zap.String("topic", topic), zap.Error(token.Error()))