问题
The topology I am looking for is
So far I have not seen a way to define the topic per message in Cloud Stream. I understand that the consumers will be bound to specific topic but how does the producer sets the topic per message before sending the message to the exchange?
source.output().send(MessageBuilder.withPayload(myMessage).build());
Does not provide any way to set the topic for the exchange to route to the proper consumer.
Or maybe I don't understand something correctly?
UPDATE
I would expect not to receive the message in the consumer due to the bindingRoutingKey
being 2222
and I am sending with routeTo
1111
. But I still receive it on the consumer.
Producer Properties:
spring.rabbitmq.host=localhost
spring.rabbitmq.port=5672
spring.rabbitmq.username=guest
spring.rabbitmq.password=guest
spring.cloud.stream.bindings.output.content-type=application/json
spring.cloud.stream.bindings.output.destination=messageExchange
spring.cloud.stream.rabbit.bindings.output.producer.routing-key-expression=headers['routeTo']
@EnableBinding(Source.class)
@SpringBootApplication
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
}
Sender:
source.output().send(MessageBuilder.withPayload(mo).setHeader("routeTo", "1111").build());
And the Consumer:
spring.rabbitmq.host=localhost
spring.rabbitmq.port=5672
spring.rabbitmq.username=guest
spring.rabbitmq.password=guest
spring.cloud.stream.bindings.input.destination=messageExchange
spring.cloud.stream.rabbit.bindings.input.consumer.bindingRoutingKey=2222
Application:
@SpringBootApplication
@EnableBinding(Sink.class)
public class Application {
private static final Logger log = LoggerFactory.getLogger(Application.class);
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
@StreamListener(Sink.INPUT)
public void ReceiveMo(String moDTO) {
log.info("Message received moDTO: {}", moDTO);
}
}
SECOND UPDATE
With the suggestions in the accepted answer below. I was able to make it work. Needed to remove the exchanges and queues from RabbitMQ using its UI and restart the RabbitMQ docker image.
回答1:
The the routingKeyExpression
rabbitmq producer property.
e.g. ...producer.routing-key-expression=headers['routeTo']
then
source.output().send(MessageBuilder.withPayload(myMessage)
.setHeader("routeTo", "Booking.new")
.build());
Note that the destination is the exchange name. By default, the binder expects a Topic
exchange. If you wish to use a Direct exchange instead, you must set the exchangeType
property.
来源:https://stackoverflow.com/questions/50190785/spring-cloud-stream-topic-per-message-for-different-consumers