| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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. |
| */ |
| |
| package org.apache.cloudstack.mom.inmemory; |
| |
| import java.util.Map; |
| import java.util.UUID; |
| import java.util.concurrent.ConcurrentHashMap; |
| |
| import javax.naming.ConfigurationException; |
| |
| import org.apache.log4j.Logger; |
| |
| import org.apache.cloudstack.framework.events.Event; |
| import org.apache.cloudstack.framework.events.EventBus; |
| import org.apache.cloudstack.framework.events.EventBusException; |
| import org.apache.cloudstack.framework.events.EventSubscriber; |
| import org.apache.cloudstack.framework.events.EventTopic; |
| |
| import com.cloud.utils.Pair; |
| import com.cloud.utils.component.ManagerBase; |
| |
| public class InMemoryEventBus extends ManagerBase implements EventBus { |
| |
| private static final Logger s_logger = Logger.getLogger(InMemoryEventBus.class); |
| |
| private final static Map<UUID, Pair<EventTopic, EventSubscriber>> subscribers; |
| |
| static { |
| subscribers = new ConcurrentHashMap<UUID, Pair<EventTopic, EventSubscriber>>(); |
| } |
| |
| @Override |
| public boolean configure(String name, Map<String, Object> params) throws ConfigurationException { |
| _name = name; |
| return true; |
| } |
| |
| @Override |
| public void setName(String name) { |
| _name = name; |
| } |
| |
| @Override |
| public UUID subscribe(EventTopic topic, EventSubscriber subscriber) throws EventBusException { |
| if (subscriber == null || topic == null) { |
| throw new EventBusException("Invalid EventSubscriber/EventTopic object passed."); |
| } |
| UUID subscriberId = UUID.randomUUID(); |
| |
| subscribers.put(subscriberId, new Pair<EventTopic, EventSubscriber>(topic, subscriber)); |
| return subscriberId; |
| } |
| |
| @Override |
| public void unsubscribe(UUID subscriberId, EventSubscriber subscriber) throws EventBusException { |
| if (subscriberId == null) { |
| throw new EventBusException("Cannot unregister a null subscriberId."); |
| } |
| |
| if (subscribers.isEmpty()) { |
| throw new EventBusException("There are no registered subscribers to unregister."); |
| } |
| |
| if (!subscribers.containsKey(subscriberId)) { |
| throw new EventBusException("No subscriber found with subscriber id " + subscriberId); |
| } else { |
| subscribers.remove(subscriberId); |
| } |
| } |
| |
| @Override |
| public void publish(Event event) throws EventBusException { |
| if (subscribers == null || subscribers.isEmpty()) { |
| return; // no subscriber to publish to, so just return |
| } |
| |
| for (UUID subscriberId : subscribers.keySet()) { |
| Pair<EventTopic, EventSubscriber> subscriberDetails = subscribers.get(subscriberId); |
| // if the event matches subscribers interested event topic then call back the subscriber with the event |
| if (isEventMatchesTopic(event, subscriberDetails.first())) { |
| EventSubscriber subscriber = subscriberDetails.second(); |
| subscriber.onEvent(event); |
| } |
| } |
| } |
| |
| @Override |
| public String getName() { |
| return _name; |
| } |
| |
| @Override |
| public boolean start() { |
| return true; |
| } |
| |
| @Override |
| public boolean stop() { |
| return true; |
| } |
| |
| public int totalSubscribers() { |
| return subscribers.size(); |
| } |
| |
| private String replaceNullWithWildcard(String key) { |
| if (key == null || key.isEmpty()) { |
| return "*"; |
| } else { |
| return key; |
| } |
| } |
| |
| private boolean isEventMatchesTopic(Event event, EventTopic topic) { |
| |
| String eventTopicSource = replaceNullWithWildcard(topic.getEventSource()); |
| eventTopicSource = eventTopicSource.replace(".", "-"); |
| String eventSource = replaceNullWithWildcard(event.getEventSource()); |
| eventSource = eventSource.replace(".", "-"); |
| if (!eventTopicSource.equals("*") && !eventSource.equals("*") && !eventTopicSource.equalsIgnoreCase(eventSource)) { |
| return false; |
| } |
| |
| String eventTopicCategory = replaceNullWithWildcard(topic.getEventCategory()); |
| eventTopicCategory = eventTopicCategory.replace(".", "-"); |
| String eventCategory = replaceNullWithWildcard(event.getEventCategory()); |
| eventCategory = eventCategory.replace(".", "-"); |
| if (!eventTopicCategory.equals("*") && !eventCategory.equals("*") && !eventTopicCategory.equalsIgnoreCase(eventCategory)) { |
| return false; |
| } |
| |
| String eventTopicType = replaceNullWithWildcard(topic.getEventType()); |
| eventTopicType = eventTopicType.replace(".", "-"); |
| String eventType = replaceNullWithWildcard(event.getEventType()); |
| eventType = eventType.replace(".", "-"); |
| if (!eventTopicType.equals("*") && !eventType.equals("*") && !eventTopicType.equalsIgnoreCase(eventType)) { |
| return false; |
| } |
| |
| String eventTopicResourceType = replaceNullWithWildcard(topic.getResourceType()); |
| eventTopicResourceType = eventTopicResourceType.replace(".", "-"); |
| String resourceType = replaceNullWithWildcard(event.getResourceType()); |
| resourceType = resourceType.replace(".", "-"); |
| if (!eventTopicResourceType.equals("*") && !resourceType.equals("*") && !eventTopicResourceType.equalsIgnoreCase(resourceType)) { |
| return false; |
| } |
| |
| String resourceUuid = replaceNullWithWildcard(event.getResourceUUID()); |
| resourceUuid = resourceUuid.replace(".", "-"); |
| String eventTopicresourceUuid = replaceNullWithWildcard(topic.getResourceUUID()); |
| eventTopicresourceUuid = eventTopicresourceUuid.replace(".", "-"); |
| if (!resourceUuid.equals("*") && !eventTopicresourceUuid.equals("*") && !resourceUuid.equalsIgnoreCase(eventTopicresourceUuid)) { |
| return false; |
| } |
| |
| return true; |
| } |
| } |