Declarabes in Spring application using Rabbit MQ

Question

I am using spring aqmp version 2.2.6 to create multiple binding to a topic exchange. I understand from the discussion and the reference document that i can use declarables .Spring AMQP: Creating multiple queues dynamically

But in my case i will have the routing keys in the application config as comma seperated and ever growing . How would i use the config to create the declarable bean dynamically. ? below is application config entry. rabbit.MQ_SUBSCRIBER_ROUTING_KEY = my.#,test.#

The routing key will be added as in when required by service .

Shoud i loop the rabbit.MQ_SUBSCRIBER_ROUTING_KEY and call bean function ?

Answer 1

my.queues=foo,bar,baz

Spring can convert that to a List<String>.

@Bean
public Declarables queues(@Value("${my.queues}") List<String> queues) {
    return new Declarables(queues
            .stream()
            .map(q -> new Queue(q))
            .collect(Collectors.toList())
            .toArray(new Queue[0]));
}

EDIT

For the complete picture:

@Bean
public Declarables declarables(@Value("${my.queues}") List<String> queues,
        @Value("${my.exchange}") String exch, 
        @Value("${my.routing.keys}") List<String> routingKeys) {

    List<Declarable> declarables = queues
                    .stream()
                    .map(q -> new Queue(q))
                    .collect(Collectors.toList());
    declarables.add(new DirectExchange(exch));
    for (int i = 0; i < routingKeys.size(); i++) {
        declarables.add(new Binding(queues.get(i), DestinationType.QUEUE, exch, 
                routingKeys.get(i), null));
    }
    return new Declarables(declarables
            .toArray(new Declarable[0]));
}

my.queues=foo,bar,baz
my.exchange=qux
my.routing.keys=rk1,rk2,rk3