add support for setting client ID

exporter/kafkaexporter/config.go

@@ -56,6 +56,10 @@ type Config struct {
 
 // Metadata defines configuration for retrieving metadata from the broker.
 type Metadata struct {
+	// ClientID to configure the Kafka client with. This can be leveraged by
+	// Kafka to enforce ACLs, throttling quotas, and more.
+	ClientID string `mapstructure:client_id`
+
 	// Whether to maintain a full set of metadata for all topics, or just
 	// the minimal set that has been necessary so far. The full set is simpler
 	// and usually more convenient, but can take up a substantial amount of

exporter/kafkaexporter/kafka_exporter.go

@@ -122,6 +122,9 @@ func (e *kafkaLogsProducer) Close(context.Context) error {
 
 func newSaramaProducer(config Config) (sarama.SyncProducer, error) {
 	c := sarama.NewConfig()
+
+	c.ClientID = config.Metadata.ClientID
+
 	// These setting are required by the sarama.SyncProducer implementation.
 	c.Producer.Return.Successes = true
 	c.Producer.Return.Errors = true