Here are some tips, including the required configurations and code samples, to help you implement a Kafka producer in Java.
Required dependencies
Ensure that you have the following dependencies in your project:
<dependency>
<groupId>org.springframework.kafka</groupId>
<artifactId>spring-kafka</artifactId>
</dependency>
<dependency>
<groupId>io.strimzi</groupId>
<artifactId>kafka-oauth-client</artifactId>
<version>0.6.1</version>
</dependency>
<dependency>
<groupId>org.apache.kafka</groupId>
<artifactId>kafka-clients</artifactId>
<version>2.5.1</version>
</dependency>
<dependency>
<groupId>io.opentracing.contrib</groupId>
<artifactId>opentracing-kafka-client</artifactId>
<version>0.1.13</version>
</dependency>
Configuration
Ensure that you have the following configuration in your application.yml or application.properties file:
spring:
kafka:
bootstrap-servers: localhost:9092
security.protocol: "PLAINTEXT"
producer:
key-serializer: org.apache.kafka.common.serialization.StringSerializer
properties:
message:
max:
bytes: ${KAFKA_MESSAGE_MAX_BYTES:52428800} #50MB
max:
request:
size: ${KAFKA_MESSAGE_MAX_BYTES:52428800} #50MB
Code sample for a Kafka producer
Ensure that you have the necessary KafkaTemplate bean autowired in your producer class. The sendMessage method demonstrates how to send a message to a Kafka topic with the specified headers and payload. Make sure to include all the received Kafka headers in the response that is sent back to the FlowX Engine.
private final KafkaTemplate<String, Object> kafkaTemplate;
public void sendMessage(String topic, Headers headers, Object payload) {
ProducerRecord<String, Object> producerRecord = new ProducerRecord<>(topic, payload);
// make sure to send all the received headers back to the FlowX Engine
headers.forEach(header -> producerRecord.headers().add(header));
kafkaTemplate.send(producerRecord);
}
