PublishToQueueVerticle.java

/*
 * Copyright 2011 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import io.vertx.core.AbstractVerticle;
import io.vertx.core.json.JsonObject;
import io.vertx.ext.amqp.*;

/**
 * Demonstrates how to use the AmqpService interface for publishing to a queue
 * within a message broker.
 * <p/>
 * This example assumes an ActiveMQ broker (or another AMQP 1.0 broker) is
 * running at localhost:6672
 * <p/>
 * 1. Run ConsumeFromQueueVerticle or another Consumer app subscribing to my-queue on the above broker<br>
 * 2. Setup an outgoing-link to 'amqp://localhost:6672/my-queue' and map it to
 * vert.x address 'my-pub-queue'.<br>
 * 3. Send a message to vert.x address 'my-pub-queue'. <br>
 * 4. The message should be received by the consumer created for 'my-sub-queue'.<br>
 * 5. When the message is accepted by the broker, we cancel the outgoing link.
 *
 * @author <a href="mailto:rajith@rajith.lk">Rajith Muditha Attapattu</a>
 */
public class PublishToQueueVerticle extends AbstractVerticle {
  private String outgoingLinkRef = null;

  private int i = 0;

  @Override
  public void start() throws Exception {
    final AMQPService service = AMQPService.createEventBusProxy(vertx, "vertx.service-amqp");
    registerForNotifications(service);

    // 1. Setup an outgoing-link to 'amqp://localhost:6672/my-queue' and map
    // it to vert.x address 'my-pub-queue'
    OutgoingLinkOptions options = new OutgoingLinkOptions();
    options.setReliability(ReliabilityMode.AT_LEAST_ONCE);

    System.out
      .println("Attempting to establish an outgoing link from the bridge to 'amqp://localhost:5672/my-queue'");
    service.establishOutgoingLink("amqp://localhost:6672/my-queue", "my-pub-queue", "my-pub-notifications",
      options, result -> {
        if (result.succeeded()) {
          outgoingLinkRef = result.result();
          System.out.println("Outgoing link ref : " + outgoingLinkRef);
          // 2. Send a message to vert.x address 'my-pub-queue'
          // Use a unique id for outgoing msg ref. When a delivery
          // notification is set, you could use this ref to
          // correlate the tracker to the original message.
          System.out.println("Sending a message to vertx address my-pub-queue");
          vertx.eventBus().publish("my-pub-queue", new JsonObject().put("body", "rajith").put(AMQPService.OUTGOING_MSG_REF, "msg-ref".concat(String.valueOf(i++))));
        } else {
          System.out.println("Error occured while setting up outgoing link from application to AMQP peer: "
            + result.cause());
          result.cause().printStackTrace();
        }
      });
  }

  private void registerForNotifications(final AMQPService service) {
    vertx.eventBus().consumer("my-pub-notifications", msg -> {
      JsonObject json = (JsonObject) msg.body();
      NotificationType type = NotificationHelper.getType(json);
      if (type == NotificationType.DELIVERY_STATE) {
        DeliveryTracker tracker = NotificationHelper.getDeliveryTracker(json);
        System.out.println("Delivery State : " + tracker.getMessageRef());
        System.out.println("Delivery State : " + tracker.getDeliveryState());
        System.out.println("Message State : " + tracker.getMessageState());
        // 5. When the message is accepted by the broker, we cancel the outgoing link.
        service.cancelOutgoingLink(outgoingLinkRef, result -> {
        });
      } else if (type == NotificationType.LINK_CREDIT) {
        System.out.println("Received " + NotificationHelper.getCredits(json) + " message credits from broker");
      }
    });
  }
}