snapshot of https://github.com/centrifugal/centrifugo.git (master, 2026-09-16; blobs > 131072B omitted)

misc/kafka_producer/main.go

@@ -0,0 +1,113 @@
+// kafka_producer produces publish commands to a Kafka topic for Centrifugo to consume.
+//
+// Usage:
+//
+//	go run ./misc/kafka_producer/ -broker localhost:29092 -topic centrifugo -channel test -interval 1s
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"flag"
+	"fmt"
+	"log"
+	"os"
+	"os/signal"
+	"strings"
+	"syscall"
+	"time"
+
+	"github.com/twmb/franz-go/pkg/kadm"
+	"github.com/twmb/franz-go/pkg/kgo"
+)
+
+type publishRequest struct {
+	Channel string          `json:"channel"`
+	Data    json.RawMessage `json:"data"`
+}
+
+type methodPayload struct {
+	Method  string          `json:"method"`
+	Payload json.RawMessage `json:"payload"`
+}
+
+func main() {
+	broker := flag.String("broker", "localhost:29092", "Kafka broker address")
+	topic := flag.String("topic", "centrifugo", "Kafka topic to produce to")
+	channel := flag.String("channel", "test", "Centrifugo channel to publish to")
+	interval := flag.Duration("interval", time.Second, "Interval between messages")
+	count := flag.Int("count", 0, "Number of messages to send (0 = unlimited)")
+	flag.Parse()
+
+	client, err := kgo.NewClient(kgo.SeedBrokers(*broker))
+	if err != nil {
+		log.Fatal("error creating Kafka client:", err)
+	}
+	defer client.Close()
+
+	ctx, cancel := signal.NotifyContext(context.Background(), os.Interrupt, syscall.SIGTERM)
+	defer cancel()
+
+	// Ensure topic exists (use a separate client since kadm.Close closes the underlying kgo client).
+	admClient, err := kgo.NewClient(kgo.SeedBrokers(*broker))
+	if err != nil {
+		log.Fatal("error creating admin client:", err)
+	}
+	adm := kadm.NewClient(admClient)
+	resp, err := adm.CreateTopics(ctx, 1, 1, nil, *topic)
+	if err != nil {
+		log.Fatal("error creating topic:", err)
+	}
+	for _, t := range resp.Sorted() {
+		if t.Err != nil && !strings.Contains(t.Err.Error(), "TOPIC_ALREADY_EXISTS") {
+			log.Fatalf("error creating topic %s: %v", t.Topic, t.Err)
+		}
+		log.Printf("topic %s ready", t.Topic)
+	}
+	adm.Close()
+
+	i := 0
+	for {
+		i++
+		if *count > 0 && i > *count {
+			break
+		}
+
+		data, _ := json.Marshal(map[string]interface{}{
+			"message": fmt.Sprintf("hello #%d", i),
+			"ts":      time.Now().UnixMilli(),
+		})
+
+		publishReq, _ := json.Marshal(publishRequest{
+			Channel: *channel,
+			Data:    data,
+		})
+
+		msg, _ := json.Marshal(methodPayload{
+			Method:  "publish",
+			Payload: publishReq,
+		})
+
+		record := &kgo.Record{
+			Topic: *topic,
+			Value: msg,
+		}
+
+		res := client.ProduceSync(ctx, record)
+		err := res.FirstErr()
+		if err != nil {
+			if ctx.Err() != nil {
+				break
+			}
+			log.Println("error producing:", err)
+		} else {
+			log.Printf("produced message #%d to topic=%s channel=%s %s (offset %d)", i, *topic, *channel, string(data), res[0].Record.Offset)
+		}
+
+		select {
+		case <-ctx.Done():
+			return
+		case <-time.After(*interval):
+		}
+	}
+}