KafkaNullConverterTest.java

/*
 * Copyright 2016-present the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.cloud.stream.binder.kafka.integration;

import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;
import java.util.function.Consumer;

import org.junit.jupiter.api.Test;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.cloud.stream.function.StreamBridge;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.kafka.annotation.KafkaListener;
import org.springframework.kafka.support.KafkaNull;
import org.springframework.kafka.test.context.EmbeddedKafka;
import org.springframework.messaging.Message;
import org.springframework.messaging.MessageChannel;
import org.springframework.messaging.handler.annotation.Payload;
import org.springframework.messaging.support.GenericMessage;
import org.springframework.test.annotation.DirtiesContext;

import static org.assertj.core.api.Assertions.assertThat;

/**
 * @author Aldo Sinanaj
 * @author Gary Russell
 * @author Soby Chacko
 */
@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.NONE, properties = {
		"spring.kafka.consumer.auto-offset-reset=earliest",
		"spring.cloud.stream.function.bindings.inputListen-in-0=kafkaNullInput"})
@DirtiesContext
@EmbeddedKafka
class KafkaNullConverterTest {

	@Autowired
	private ApplicationContext context;

	@Autowired
	private KafkaNullConverterTestConfig config;

	@Test
	void kafkaNullConverterOutput() throws InterruptedException {
		final StreamBridge streamBridge = context.getBean(StreamBridge.class);

		streamBridge.send("kafkaNullOutput", new GenericMessage<>(KafkaNull.INSTANCE));

		assertThat(this.config.countDownLatchOutput.await(10, TimeUnit.SECONDS)).isTrue();
		assertThat(this.config.outputPayload).isNull();
	}

	@Test
	void kafkaNullConverterInput() throws InterruptedException {

		final MessageChannel kafkaNullInput = context.getBean("kafkaNullInput", MessageChannel.class);

		kafkaNullInput.send(new GenericMessage<>(KafkaNull.INSTANCE));

		assertThat(this.config.countDownLatchInput.await(10, TimeUnit.SECONDS)).isTrue();
		assertThat(this.config.inputPayload).isNull();
	}

	@EnableAutoConfiguration
	@Configuration
	public static class KafkaNullConverterTestConfig {

		final CountDownLatch countDownLatchOutput = new CountDownLatch(1);

		final CountDownLatch countDownLatchInput = new CountDownLatch(1);

		volatile byte[] outputPayload = new byte[0];

		volatile byte[] inputPayload = new byte[0];

		@KafkaListener(id = "foo", topics = "kafkaNullOutput")
		public void listen(@Payload(required = false) byte[] in) {
			this.outputPayload = in;
			countDownLatchOutput.countDown();
		}

		@Bean
		public Consumer<Message<byte[]>> inputListen() {
			return in -> {
				Object v = in.getPayload();
				String className = v.getClass().getName();
				if (className.equals("org.springframework.kafka.support.KafkaNull")) {
					this.inputPayload = null;
				}
				countDownLatchInput.countDown();
			};
		}

	}
}