Need an example on Embedded kafka with camel - spring

Question

I am facing issue while testing kafka with camel. I used Embedded kafka with camel and here's what I tried
I have tried this example which tells us about testing kafka using embedded kafka
https://codenotfound.com/spring-kafka-embedded-unit-test-example.html
package com.codenotfound.kafka.producer;
import static org.assertj.core.api.Assertions.assertThat;
import static org.junit.Assert.assertThat;
import static org.springframework.kafka.test.assertj.KafkaConditions.key;
import static org.springframework.kafka.test.hamcrest.KafkaMatchers.hasValue;
import java.util.Map;
import java.util.Map.Entry;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.TimeUnit;
import org.apache.camel.builder.RouteBuilder;
import org.apache.camel.main.Main;
import org.apache.kafka.clients.consumer.ConsumerRecord;
import org.junit.After;
import org.junit.Before;
import org.junit.ClassRule;
import org.junit.Ignore;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.kafka.core.DefaultKafkaConsumerFactory;
import org.springframework.kafka.listener.ContainerProperties;
import org.springframework.kafka.listener.KafkaMessageListenerContainer;
import org.springframework.kafka.listener.MessageListener;
import org.springframework.kafka.test.rule.EmbeddedKafkaRule;
import org.springframework.kafka.test.utils.ContainerTestUtils;
import org.springframework.kafka.test.utils.KafkaTestUtils;
import org.springframework.test.annotation.DirtiesContext;
import org.springframework.test.context.junit4.SpringRunner;
#RunWith(SpringRunner.class)
#SpringBootTest
#DirtiesContext
public class SpringKafkaSenderTest {
private static final Logger LOGGER = LoggerFactory.getLogger(SpringKafkaSenderTest.class);
private static String SENDER_TOPIC = "sender.t";
#Autowired
private Sender sender;
private KafkaMessageListenerContainer<String, String> container;
private BlockingQueue<ConsumerRecord<String, String>> records;
Object groupId;
Object bootstrapServers;
#ClassRule
public static EmbeddedKafkaRule embeddedKafka = new EmbeddedKafkaRule(1, true, SENDER_TOPIC);
#Before
public void setUp() throws Exception {
// set up the Kafka consumer properties
Map<String, Object> consumerProperties = KafkaTestUtils.consumerProps("sender", "false",
embeddedKafka.getEmbeddedKafka());
for (Entry<String, Object> entry : consumerProperties.entrySet()) {
System.out.println("Key = " + entry.getKey() + ", Value = " + entry.getValue());
if (entry.getKey().equals("group.id")) {
groupId = entry.getValue();
} else if (entry.getKey().equals("bootstrap.servers")) {
bootstrapServers = entry.getValue();
}
}
// create a Kafka consumer factory
DefaultKafkaConsumerFactory<String, String> consumerFactory = new DefaultKafkaConsumerFactory<String, String>(
consumerProperties);
// set the topic that needs to be consumed
ContainerProperties containerProperties = new ContainerProperties(SENDER_TOPIC);
// create a Kafka MessageListenerContainer
container = new KafkaMessageListenerContainer<>(consumerFactory, containerProperties);
// create a thread safe queue to store the received message
records = new LinkedBlockingQueue<>();
// setup a Kafka message listener
container.setupMessageListener(new MessageListener<String, String>() {
#Override
public void onMessage(ConsumerRecord<String, String> record) {
LOGGER.debug("test-listener received message='{}'", record.toString());
records.add(record);
}
});
// start the container and underlying message listener
container.start();
// wait until the container has the required number of assigned partitions
ContainerTestUtils.waitForAssignment(container, embeddedKafka.getEmbeddedKafka().getPartitionsPerTopic());
}
#After
public void tearDown() {
// stop the container
container.stop();
}
#Test
public void testCamelWithKafka() throws Exception {
String topicName = "topic=javainuse-topic";
String kafkaServer = "kafka:localhost:9092";
String zooKeeperHost = "zookeeperHost=localhost&zookeeperPort=2181";
String serializerClass = "serializerClass=kafka.serializer.StringEncoder";
String toKafka = new StringBuilder().append(kafkaServer).append("?").append(topicName).append("&")
.append(zooKeeperHost).append("&").append(serializerClass).toString();
String embedded = new StringBuilder().append(bootstrapServers).append("?").append(topicName).append("&")
// .append(embeddedKafka.getEmbeddedKafka().getZookeeperConnectionString())
.append(zooKeeperHost).append("&").append(serializerClass).toString();
Main main = new Main();
main.addRouteBuilder(new RouteBuilder() {
#Override
public void configure() throws Exception {
from("file:D://inbox//?noop=true").split().tokenize("\n").to("direct:embedded");
}
});
main.run();
ConsumerRecord<String, String> received =
records.poll(10, TimeUnit.SECONDS);
// assertThat(received, hasValue(greeting));
// AssertJ Condition to check the key
// assertThat(received).has(key(null));
// System.out.println(received);
}
}
Camel should able to read from a file and move the data to kafka and consumer should able to read it.

Answer 1

You can use the #Runwith(CamelSpringBootRunner.class) to run the test case.