Converter issue with TestRabbitTemplate (Spring AMQP)

Question

I am trying to run an integration test for my RabbitListener in Spring AMQP while the broker is not running so I am using TestRabbitTemplate. I am using a Jacksonized object and the Jackson2JsonMessageConverter was set for the TestRabbitTemplate. However upon sending a message to the exchange, I am getting the following exception.

org.springframework.amqp.rabbit.support.ListenerExecutionFailedException: Listener method could not be invoked with the incoming message
Caused by: org.springframework.messaging.converter.MessageConversionException: Cannot convert from [[B] to [com.murex.em.demo.springamqpdemo.message.CustomMessage] for GenericMessage [payload=byte[27], headers={amqp_contentEncoding=UTF-8, amqp_contentLength=27, amqp_replyTo=testRabbitTemplateReplyTo, id=fb0352d2-2abb-ae06-9b2e-03da1fc19e43, amqp_lastInBatch=false, contentType=application/json, __TypeId__=com.murex.em.demo.springamqpdemo.message.CustomMessage, timestamp=1676625212607}], failedMessage=GenericMessage [payload=byte[27], headers={amqp_contentEncoding=UTF-8, amqp_contentLength=27, amqp_replyTo=testRabbitTemplateReplyTo, id=fb0352d2-2abb-ae06-9b2e-03da1fc19e43, amqp_lastInBatch=false, contentType=application/json, __TypeId__=com.murex.em.demo.springamqpdemo.message.CustomMessage, timestamp=1676625212607}]
    at org.springframework.messaging.handler.annotation.support.PayloadMethodArgumentResolver.resolveArgument(PayloadMethodArgumentResolver.java:145)
    at org.springframework.amqp.rabbit.annotation.RabbitListenerAnnotationBeanPostProcessor$OptionalEmptyAwarePayloadArgumentResolver.resolveArgument(RabbitListenerAnnotationBeanPostProcessor.java:1053)
    at org.springframework.messaging.handler.invocation.HandlerMethodArgumentResolverComposite.resolveArgument(HandlerMethodArgumentResolverComposite.java:118)
    at org.springframework.messaging.handler.invocation.InvocableHandlerMethod.getMethodArgumentValues(InvocableHandlerMethod.java:147)
    at org.springframework.messaging.handler.invocation.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:115)
    at org.springframework.amqp.rabbit.listener.adapter.HandlerAdapter.invoke(HandlerAdapter.java:77)
    at org.springframework.amqp.rabbit.listener.adapter.MessagingMessageListenerAdapter.invokeHandler(MessagingMessageListenerAdapter.java:263)
    ... 78 more

Here are the relevant chunks of my code:

@Jacksonized
@Builder
@Value
public class CustomMessage {

    String id;

    String name;

}

@Component
public class InwardMessageConsumer {

    @RabbitListener(bindings = @QueueBinding(
            value = @Queue(name = "inward.messageQueue", durable = "true"),
            exchange = @Exchange(value = "inward", type = "topic"),
            key = "inwardRoutingKey")
    )
    public String processMessage(CustomMessage customMessage) {
        return customMessage.getName();

    }

}

@SpringJUnitConfig
@SpringBootTest
class BrokerNotRunningIT {

    @Autowired
    private TestRabbitTemplate template;

    @Test
    public void testSendAndReceive() {
        CustomMessage customMessage = CustomMessage.builder()
                .id("123")
                .name("name1")
                .build();

        assertThat(template.convertSendAndReceive("inward", "inward.messageQueue", customMessage)).isEqualTo("name1");
    }

    @TestConfiguration
    public static class RabbitTestConfiguration {

        @Bean
        public TestRabbitTemplate testRabbitTemplate(
                ConnectionFactory mockConnectionFactory,
                Jackson2JsonMessageConverter jackson2JsonMessageConverter
        ) {
            TestRabbitTemplate testRabbitTemplate = new TestRabbitTemplate(mockConnectionFactory);
            testRabbitTemplate.setMessageConverter(jackson2JsonMessageConverter);
            return testRabbitTemplate;
        }

        @Bean
        public ConnectionFactory mockConnectionFactory() throws IOException {
            ConnectionFactory factory = mock(ConnectionFactory.class);
            Connection connection = mock(Connection.class);
            Channel channel = mock(Channel.class);
            AMQP.Queue.DeclareOk declareOk = mock(AMQP.Queue.DeclareOk.class);
            willReturn(connection).given(factory).createConnection();
            willReturn(channel).given(connection).createChannel(anyBoolean());
            given(channel.isOpen()).willReturn(true);
            given(channel.queueDeclare(anyString(), anyBoolean(), anyBoolean(), anyBoolean(), anyMap()))
                    .willReturn(declareOk);
            return factory;
        }

        @Bean
        public SimpleRabbitListenerContainerFactory rabbitListenerContainerFactory(ConnectionFactory connectionFactory) {
            SimpleRabbitListenerContainerFactory factory = new SimpleRabbitListenerContainerFactory();
            factory.setConnectionFactory(connectionFactory);
            return factory;
        }

        @Bean
        public SimpleMessageListenerContainer simpleMessageListenerContainer(ConnectionFactory connectionFactory) {
            return new SimpleMessageListenerContainer(connectionFactory);
        }
    }
}

Answer 1

Apparently I needed to set the message converter in the RabbitListenerContainerFactory as well like this:

@Bean
        public SimpleRabbitListenerContainerFactory rabbitListenerContainerFactory(ConnectionFactory connectionFactory, Jackson2JsonMessageConverter jackson2JsonMessageConverter) {
            SimpleRabbitListenerContainerFactory factory = new SimpleRabbitListenerContainerFactory();
            factory.setConnectionFactory(connectionFactory);
            factory.setMessageConverter(jackson2JsonMessageConverter);
            return factory;
        }