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spring-amqp

Reply Message post processing in AsyncRabbitTemplate

I'm running into trouble with GZip/GUnzip message processing when using the AsyncRabbitTemplate.

Things work fine with an synchronous template setup like so:

@Bean
@Scope(ConfigurableBeanFactory.SCOPE_PROTOTYPE)
public RabbitTemplate rabbitTemplate(final ConnectionFactory connectionFactory) {
    final RabbitTemplate rabbitTemplate = new RabbitTemplate(connectionFactory);
    rabbitTemplate.setMessageConverter(jsonConverter());
    rabbitTemplate.setReplyTimeout(config.getRabbitSendAndReceiveReplyTimeout());
    rabbitTemplate.setReceiveTimeout(config.getRabbitSendAndReceiveReceiveTimeout());
    rabbitTemplate.setAfterReceivePostProcessors(new GUnzipPostProcessor(true));
    rabbitTemplate.setBeforePublishPostProcessors(new GZipPostProcessor(true));
    return rabbitTemplate;
}

However, when I setup an async template like this:

@Bean
@Scope(ConfigurableBeanFactory.SCOPE_PROTOTYPE)
public AsyncRabbitTemplate rabbitTemplateAsync(final ConnectionFactory connectionFactory) {
    final AsyncRabbitTemplate asyncRabbitTemplate = new AsyncRabbitTemplate(rabbitTemplate(connectionFactory));
    // need to manually start the reply listener container for some reason
    asyncRabbitTemplate.start();
    return asyncRabbitTemplate;
}

The reply message isn't unzipped properly, and I get this error message

Caused by: java.io.UnsupportedEncodingException: gzip:UTF-8
    at java.lang.StringCoding.decode(Unknown Source) ~[?:1.8.0_192]
    at java.lang.String.<init>(Unknown Source) ~[?:1.8.0_192]
    at java.lang.String.<init>(Unknown Source) ~[?:1.8.0_192]
    at org.springframework.amqp.support.converter.AbstractJackson2MessageConverter.convertBytesToObject(AbstractJackson2MessageConverter.java:235) ~[spring-amqp-2.1.4.RELEASE.jar:2.1.4.RELEASE]
    at org.springframework.amqp.support.converter.AbstractJackson2MessageConverter.fromMessage(AbstractJackson2MessageConverter.java:199) ~[spring-amqp-2.1.4.RELEASE.jar:2.1.4.RELEASE]
    at org.springframework.amqp.rabbit.AsyncRabbitTemplate.onMessage(AsyncRabbitTemplate.java:576) ~[spring-rabbit-2.1.4.RELEASE.jar:2.1.4.RELEASE]

I've tried giving the AsyncRabbitTemplate a configured DirectReplyToMessageListenerContainer, but it doesn't help

    final DirectReplyToMessageListenerContainer directReplyToMessageListenerContainer = new DirectReplyToMessageListenerContainer(
            connectionFactory);
    directReplyToMessageListenerContainer.setAfterReceivePostProcessors(new GUnzipPostProcessor(true));
    final AsyncRabbitTemplate asyncRabbitTemplate = new AsyncRabbitTemplate(rabbitTemplate(connectionFactory),
            directReplyToMessageListenerContainer);

This just results in this error:

[ERROR] 2019-03-06 12:18:05.192 [AMQP Connection 172.17.3.6:5672] CachingConnectionFactory.log - Channel shutdown: channel error; protocol method: #method(reply-code=406, reply-text=PRECONDITION_FAILED - fast reply consumer does not exist, class-id=60, method-id=40)

Note that I was able to get things working by taking a branch of the spring-rabbit project and adding this constructor to AsyncRabbitTemplate:

public IndigoAsyncRabbitTemplate(final RabbitTemplate template,
        final DirectReplyToMessageListenerContainer directReplyToContainer) {
    Assert.notNull(template, "'template' cannot be null");
    this.template = template;
    container = null;
    replyAddress = null;
    this.directReplyToContainer = directReplyToContainer;
    directReplyToContainer.setMessageListener(this);
}

So, is this going to take an enhancement to the spring rabbit library to get working? Or is there a way to get GUnzip working on the reply listener without jumping through too many hoops?

Solution

  • Right, this has to go as an improvement into the framework. We are just missing the fact of the afterReceivePostProcessors in case of AsyncRabbitTemplate. We can re-configure an internal DirectReplyToMessageListenerContainer to use afterReceivePostProcessors from the provided RabbitTemplate.

    Meanwhile you can stick with a regular SimpleMessageListenerContainer injection. Or you can try with an external DirectReplyToMessageListenerContainer injection though.

    See this ctor:

    /**
 * Construct an instance using the provided arguments. The first queue the container
 * is configured to listen to will be used as the reply queue. Replies will be
 * routed using the default exchange with that queue name as the routing key.
 * @param template a {@link RabbitTemplate}
 * @param container a {@link AbstractMessageListenerContainer}.
 */
public AsyncRabbitTemplate(RabbitTemplate template, AbstractMessageListenerContainer container) {
    this(template, container, null);
}

    The issue on the matter: https://github.com/spring-projects/spring-amqp/issues/920