001/**
002 * Copyright 2005-2016 The Kuali Foundation
003 *
004 * Licensed under the Educational Community License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.opensource.org/licenses/ecl2.php
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016package org.kuali.rice.ksb.messaging;
017
018import org.apache.log4j.Logger;
019import org.kuali.rice.core.api.config.property.ConfigContext;
020import org.kuali.rice.ksb.messaging.service.MessageQueueService;
021import org.kuali.rice.ksb.service.KSBServiceLocator;
022import org.kuali.rice.ksb.util.KSBConstants;
023import org.kuali.rice.ksb.util.KSBConstants.Config;
024import org.springframework.transaction.TransactionStatus;
025import org.springframework.transaction.support.TransactionCallback;
026
027/**
028 * Fetches messages from the db. Marks as 'R'. Gives messages to ThreadPool for execution
029 * 
030 * @author Kuali Rice Team (rice.collab@kuali.org)
031 * 
032 */
033public class MessageFetcher implements Runnable {
034
035    private static final Logger LOG = Logger.getLogger(MessageFetcher.class);
036
037    private Integer maxMessages;
038    private Long routeQueueId;
039
040    public MessageFetcher(Integer maxMessages) {
041        this.maxMessages = maxMessages;
042    }
043
044    public MessageFetcher(Long routeQueueId) {
045        this.routeQueueId = routeQueueId;
046    }
047
048    public void run() {
049        if (ConfigContext.getCurrentContextConfig().getBooleanProperty(KSBConstants.Config.MESSAGE_PERSISTENCE, false)) {
050                try {
051                        requeueDocument();
052                        requeueMessages();
053                } catch (Throwable t) {
054                        LOG.error("Failed to fetch messages.", t);
055                }
056        }
057    }
058
059    private void requeueMessages() {
060        if (this.routeQueueId == null) {
061            try {
062                for (final PersistedMessageBO message : getRouteQueueService().getNextDocuments(maxMessages)) {
063                    markEnrouteAndSaveMessage(message);
064                    executeMessage(message);
065                }
066            } catch (Throwable t) {
067                LOG.error("Failed to fetch or process some messages during requeueMessages", t);
068            }
069        }
070    }
071
072    private void requeueDocument() {
073        try {
074            if (this.routeQueueId != null) {
075                PersistedMessageBO message = getRouteQueueService().findByRouteQueueId(this.routeQueueId);
076                message.setQueueStatus(KSBConstants.ROUTE_QUEUE_ROUTING);
077                getRouteQueueService().save(message);
078                executeMessage(message);
079            }
080        } catch (Throwable t) {
081            LOG.error("Failed to fetch or process some messages during requeueDocument", t);
082        }
083    }
084
085    private void executeMessage(PersistedMessageBO message) {
086        try {
087            KSBServiceLocator.getThreadPool().execute(new MessageServiceInvoker(message));
088        } catch (Throwable t) {
089            LOG.error("Failed to place message " + message + " in thread pool for execution", t);
090        }
091    }
092
093    private void markEnrouteAndSaveMessage(final PersistedMessageBO message) {
094        try {
095            KSBServiceLocator.getTransactionTemplate().execute(new TransactionCallback() {
096                public Object doInTransaction(TransactionStatus status) {
097                    message.setQueueStatus(KSBConstants.ROUTE_QUEUE_ROUTING);
098                    getRouteQueueService().save(message);
099                    return null;
100                }
101            });
102        } catch (Throwable t) {
103            LOG.error("Caught error attempting to mark message " + message + " as R", t);
104        }
105    }
106
107    private MessageQueueService getRouteQueueService() {
108        return KSBServiceLocator.getMessageQueueService();
109    }
110
111}