Akka、Camel和HTTP轮询

Answer 1

您有两个选项（示例代码用Java编写）：

1）使用“计时器”（或更高级的quartz）Camel组件。然后，您需要一个非常简单的计时器执行器，它在每个句点调用一个新的HTTProducer执行器：

    public class TimerConsumer extends UntypedConsumerActor{

    //Generates an event every 60 seconds:
    @Override
    public String getEndpointUri() {
        return "timer://foo?fixedRate=true&period=15000";
    }

    @Override
    public void onReceive(Object m) throws Exception {
        if (m instanceof CamelMessage){
            System.out.println("New Event (every 15sec)");
            Akka.system().actorOf(Props.create(HTTProducer.class)).tell("http://google.com", getSelf());
        }
    }
}

2）使用Akka调度程序

//Somewhere in the beginning of your application (Global.java for Play Framework 2)
ActorRef httpActor = Akka.system().actorOf(Props.create(HTTProducer.class));
//A message every 15s to the httpActor
Akka.system().scheduler().schedule(Duration.Zero(),
Duration.create(15, TimeUnit.SECONDS), httpActor, "http://google.com",
Akka.system().dispatcher(), null);

public class HTTProducer extends UntypedProducerActor {

    @Override
    public String getEndpointUri() {
        return "http://empty.com";
    }

    @Override
    public Object onTransformOutgoingMessage(Object m) {
        if (m instanceof String){
            Map<String,Object> headers=new HashMap<>();
            headers.put(Exchange.HTTP_URI, (String)m);
            headers.put(Exchange.HTTP_METHOD, "GET");
            return super.onTransformOutgoingMessage(new CamelMessage(null,headers));
        }
        return super.onTransformOutgoingMessage(m);
    }

    @Override
    public void onRouteResponse(Object m) {
        if (m instanceof CamelMessage){
            CamelMessage message=(CamelMessage) m;
            System.out.println("Response: " + message.getBodyAs(String.class, getCamelContext()));
            System.out.println("Code: " + message.headers().get(Exchange.HTTP_RESPONSE_CODE).get());
        }
    }