docs: add producer interceptor example

README.md

@@ -196,6 +196,10 @@ After running `docker-compose up` command, you can run any application you want.
 
 </details>
 
+#### With Producer Interceptor
+
+Please refer to [Producer Interceptor Example](examples/with-kafka-producer-interceptor)
+
 #### With Distributed Tracing Support
 
 Please refer to [Tracing Example](examples/with-tracing/README.md)

examples/with-kafka-producer-interceptor/main.go

@@ -0,0 +1,38 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"github.com/Trendyol/kafka-konsumer/v2"
+)
+
+func main() {
+	producer, _ := kafka.NewProducer(&kafka.ProducerConfig{
+		Writer: kafka.WriterConfig{
+			Brokers: []string{"localhost:29092"},
+		},
+	}, newProducerInterceptor()...)
+
+	const topicName = "standart-topic"
+
+	_ = producer.Produce(context.Background(), kafka.Message{
+		Topic: topicName,
+		Key:   []byte("1"),
+		Value: []byte(`{ "foo": "bar" }`),
+	})
+
+	_ = producer.ProduceBatch(context.Background(), []kafka.Message{
+		{
+			Topic: topicName,
+			Key:   []byte("1"),
+			Value: []byte(`{ "foo": "bar" }`),
+		},
+		{
+			Topic: topicName,
+			Key:   []byte("2"),
+			Value: []byte(`{ "foo2": "bar2" }`),
+		},
+	})
+
+	fmt.Println("Messages sended...!")
+}

examples/with-kafka-producer-interceptor/producer-interceptor.go

@@ -0,0 +1,16 @@
+package main
+
+import "github.com/Trendyol/kafka-konsumer/v2"
+
+type producerInterceptor struct{}
+
+func (i *producerInterceptor) OnProduce(ctx kafka.ProducerInterceptorContext) {
+	ctx.Message.Headers = append(ctx.Message.Headers, kafka.Header{
+		Key:   "x-source-app",
+		Value: []byte("kafka-konsumer"),
+	})
+}
+
+func newProducerInterceptor() []kafka.ProducerInterceptor {
+	return []kafka.ProducerInterceptor{&producerInterceptor{}}
+}