What is Kafka and How to use Kafka with SpringBoot and Apache Camel?

Jasvinder S Saggu
2 min readJul 10, 2021

docker-compose.yml

version: '3.2'
services:
zookeeper:
image: confluentinc/cp-zookeeper:latest
environment:
ZOOKEEPER_CLIENT_PORT: 2181
ZOOKEEPER_TICK_TIME: 2000
ports:
- 22181:2181

kafka:
image: confluentinc/cp-kafka:latest
depends_on:
- zookeeper
ports:
- 29092:29092
environment:
KAFKA_BROKER_ID: 1
KAFKA_ZOOKEEPER_CONNECT: zookeeper:2181
KAFKA_ADVERTISED_LISTENERS: PLAINTEXT://kafka:9092,PLAINTEXT_HOST://localhost:29092
KAFKA_LISTENER_SECURITY_PROTOCOL_MAP: PLAINTEXT:PLAINTEXT,PLAINTEXT_HOST:PLAINTEXT
KAFKA_INTER_BROKER_LISTENER_NAME: PLAINTEXT
KAFKA_OFFSETS_TOPIC_REPLICATION_FACTOR: 1

CamelApplication.java

package com.jss.camel;

import org.apache.camel.ProducerTemplate;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.ComponentScan;

@SpringBootApplication
@ComponentScan(basePackages = {"com.jss"})
public class CamelApplication {
@Autowired
ProducerTemplate producerTemplate;

public static void main(String[] args) throws InterruptedException {
SpringApplication.run(CamelApplication.class, args);
}
}

StockKafkaRoute.java

package com.jss.camel.components.routes.kafka;

import org.apache.camel.builder.RouteBuilder;
import org.springframework.stereotype.Component;

import java.util.Date;

import static org.apache.camel.LoggingLevel.ERROR;

@Component
public class StockKafkaRoute extends RouteBuilder {

final String KAFKA_ENDPOINT = "kafka:%s?brokers=localhost:29092";

@Override
public void configure() throws Exception {
fromF(KAFKA_ENDPOINT, "stock-live")
.log(ERROR, "[${header.kafka.OFFSET}] [${body}]")
.bean(StockPriceEnricher.class)
.toF(KAFKA_ENDPOINT, "stock-audit")
;
}

private class StockPriceEnricher {
public String enrichStockPrice(String stockPrice) {
return stockPrice + "," + new Date();
}
}
}

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.4.7</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.jss</groupId>
<artifactId>camel</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>camel</name>
<description>Apache Camel with Spring Boot</description>

<properties>
<java.version>1.8</java.version>
<junit.platform.version>1.6.0</junit.platform.version>
<camel.version>3.7.3</camel.version>
</properties>

<dependencies>
<dependency>
<groupId>org.apache.camel.springboot</groupId>
<artifactId>camel-spring-boot-starter</artifactId>
<version>${camel.version}</version>
</dependency>

<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>

<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>

<dependency>
<groupId>org.apache.camel</groupId>
<artifactId>camel-test</artifactId>
<scope>test</scope>
<version>${camel.version}</version>
</dependency>

<dependency>
<groupId>org.apache.camel</groupId>
<artifactId>camel-rabbitmq</artifactId>
<version>${camel.version}</version>
</dependency>

<dependency>
<groupId>org.apache.camel</groupId>
<artifactId>camel-jackson</artifactId>
<version>${camel.version}</version>
</dependency>

<dependency>
<groupId>org.apache.camel</groupId>
<artifactId>camel-jaxb</artifactId>
<version>${camel.version}</version>
</dependency>

<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
<version>1.18.12</version>
</dependency>

<dependency>
<groupId>org.apache.camel</groupId>
<artifactId>camel-servlet</artifactId>
<version>${camel.version}</version>
</dependency>

<dependency>
<groupId>org.apache.camel.springboot</groupId>
<artifactId>camel-servlet-starter</artifactId>
<version>${camel.version}</version>
</dependency>

<dependency>
<groupId>org.apache.camel.springboot</groupId>
<artifactId>camel-rest-starter</artifactId>
<version>${camel.version}</version>
</dependency>

<dependency>
<groupId>org.apache.camel</groupId>
<artifactId>camel-kafka</artifactId>
<version>${camel.version}</version>
</dependency>

<dependency>
<groupId>org.junit.platform</groupId>
<artifactId>junit-platform-runner</artifactId>
<version>${junit.platform.version}</version>
<scope>test</scope>
</dependency>

<dependency>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
<version>5.7.0</version>
<scope>test</scope>
</dependency>

<dependency>
<groupId>org.apache.camel</groupId>
<artifactId>camel-test-junit5</artifactId>
<version>${camel.version}</version>
<scope>test</scope>
</dependency>

<dependency>
<groupId>org.apache.camel</groupId>
<artifactId>camel-test-spring-junit5</artifactId>
<version>${camel.version}</version>
<scope>test</scope>
</dependency>

</dependencies>

<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>

</project>

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