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spring-bootkotlinspring-amqp

is it possible to declare these bindings with RabbitListener?

given this code


    @Bean
    open fun exchange(): TopicExchange {
        return TopicExchange("amq.topic")
    }


    @RabbitListener(queues = [Amqp.BODY_WEIGHT_NEW])
    open fun record(entity: Collection<BodyWeight>) {
        log.trace("saving: {}", entity)
    }

    @Bean
    open fun weight(): Queue {
        return Queue(Amqp.BODY_WEIGHT_NEW)
    }

    @Bean
    open fun bindWeight(): Binding {
        return BindingBuilder.bind(weight()).to(exchange).with(Amqp.BODY_WEIGHT_NEW)
    }

is it possible to reduce my @Bean declarations using @RabbitListener? I know I can list the queue as a queue to declare, but I'm not sure on what the bindings would look like.

tried this

    @RabbitListener(bindings = [QueueBinding(value = Queue(Amqp.BODY_WEIGHT_NEW), exchange = Exchange("amqp.topic"))])

but it doesn't seem to bind to the exchange in the same way, as my tests aren't passing.

Solution

  • You need to add the routing key to the @QueueBinding...

    key = Amqp.BODY_WEIGHT_NEW

    (that's what the with clause on the BindingBuilder does).

    EDIT

    Works fine for me...

    @SpringBootApplication
open class So55928905Application {

    @RabbitListener(bindings = [QueueBinding(value = Queue("foo"), 
                                  exchange = Exchange("amqp.topic"), 
                                  key = ["foo"])])
    fun `in`(`in`: String) {

    }

    companion object {

        @JvmStatic
        fun main(args: Array<String>) {
            SpringApplication.run(So55928905Application::class.java, *args)
        }
    }

}

    enter image description here

    EDIT2

    The problem is your exchange name MQTT publishes to the standard amq.topic not amqp.topic.

    @SpringBootApplication
open class So55928905Application {

    @RabbitListener(bindings = [QueueBinding(value = Queue("foo"),
                        exchange = Exchange(name = "amq.topic", type = "topic"),
                        key = ["foo"])])
    fun listen(string: String) {
        println(string)
    }

    companion object {

        @JvmStatic
        fun main(args: Array<String>) {
            SpringApplication.run(So55928905Application::class.java, *args)
        }
    }

}