Add consume ability to sasl_scram_client example

examples/sasl_scram_client/main.go

@@ -7,6 +7,7 @@ import (
 	"io/ioutil"
 	"log"
 	"os"
+	"os/signal"
 	"strings"
 
 	"github.com/Shopify/sarama"
@@ -27,6 +28,8 @@ var (
 	caFile    = flag.String("ca", "", "The optional certificate authority file for TLS client authentication")
 	verifySSL = flag.Bool("verify", false, "Optional verify ssl certificates chain")
 	useTLS    = flag.Bool("tls", false, "Use TLS to communicate with the cluster")
+	mode      = flag.String("mode", "produce", "Mode to run in: \"produce\" to produce, \"consume\" to consume")
+	logMsg    = flag.Bool("logmsg", false, "True to log consumed messages to console")
 
 	logger = log.New(os.Stdout, "[Producer] ", log.LstdFlags)
 )
@@ -62,8 +65,9 @@ func main() {
 	flag.Parse()
 
 	if *brokers == "" {
-		log.Fatalln("at least one brocker is required")
+		log.Fatalln("at least one broker is required")
 	}
+	splitBrokers := strings.Split(*brokers, ",")
 
 	if *userName == "" {
 		log.Fatalln("SASL username is required")
@@ -101,18 +105,66 @@ func main() {
 		conf.Net.TLS.Config = createTLSConfiguration()
 	}
 
-	syncProcuder, err := sarama.NewSyncProducer(strings.Split(*brokers, ","), conf)
-	if err != nil {
-		logger.Fatalln("failed to create producer: ", err)
-	}
-	partition, offset, err := syncProcuder.SendMessage(&sarama.ProducerMessage{
-		Topic: *topic,
-		Value: sarama.StringEncoder("test_message"),
-	})
-	if err != nil {
-		logger.Fatalln("failed to send message to ", *topic, err)
+	if *mode == "consume" {
+		consumer, err := sarama.NewConsumer(splitBrokers, conf)
+		if err != nil {
+			panic(err)
+		}
+		log.Println("consumer created")
+		defer func() {
+			if err := consumer.Close(); err != nil {
+				log.Fatalln(err)
+			}
+		}()
+		log.Println("commence consuming")
+		partitionConsumer, err := consumer.ConsumePartition(*topic, 0, sarama.OffsetOldest)
+		if err != nil {
+			panic(err)
+		}
+
+		defer func() {
+			if err := partitionConsumer.Close(); err != nil {
+				log.Fatalln(err)
+			}
+		}()
+
+		// Trap SIGINT to trigger a shutdown.
+		signals := make(chan os.Signal, 1)
+		signal.Notify(signals, os.Interrupt)
+
+		consumed := 0
+	ConsumerLoop:
+		for {
+			log.Println("in the for")
+			select {
+			case msg := <-partitionConsumer.Messages():
+				log.Printf("Consumed message offset %d\n", msg.Offset)
+				if *logMsg {
+					log.Printf("KEY: %s VALUE: %s", msg.Key, msg.Value)
+				}
+				consumed++
+			case <-signals:
+				break ConsumerLoop
+			}
+		}
+
+		log.Printf("Consumed: %d\n", consumed)
+
+	} else {
+		syncProducer, err := sarama.NewSyncProducer(splitBrokers, conf)
+		if err != nil {
+			logger.Fatalln("failed to create producer: ", err)
+		}
+		partition, offset, err := syncProducer.SendMessage(&sarama.ProducerMessage{
+			Topic: *topic,
+			Value: sarama.StringEncoder("test_message"),
+		})
+		if err != nil {
+			logger.Fatalln("failed to send message to ", *topic, err)
+		}
+		logger.Printf("wrote message at partition: %d, offset: %d", partition, offset)
+		_ = syncProducer.Close()
 	}
-	logger.Printf("wrote message at partition: %d, offset: %d", partition, offset)
-	_ = syncProcuder.Close()
 	logger.Println("Bye now !")
+
 }