001    /**
002     * Copyright (c) 2010 Yahoo! Inc. All rights reserved.
003     * Licensed under the Apache License, Version 2.0 (the "License");
004     * you may not use this file except in compliance with the License.
005     * You may obtain a copy of the License at
006     *
007     *   http://www.apache.org/licenses/LICENSE-2.0
008     *
009     *  Unless required by applicable law or agreed to in writing, software
010     *  distributed under the License is distributed on an "AS IS" BASIS,
011     *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012     *  See the License for the specific language governing permissions and
013     *  limitations under the License. See accompanying LICENSE file.
014     */
015    package org.apache.oozie.servlet;
016    
017    import java.io.IOException;
018    import java.util.Arrays;
019    import java.util.List;
020    
021    import javax.servlet.ServletException;
022    import javax.servlet.http.HttpServletRequest;
023    import javax.servlet.http.HttpServletResponse;
024    
025    import org.apache.oozie.ErrorCode;
026    import org.apache.oozie.SLAEventBean;
027    import org.apache.oozie.XException;
028    import org.apache.oozie.client.rest.RestConstants;
029    import org.apache.oozie.command.CommandException;
030    import org.apache.oozie.command.coord.SLAEventsCommand;
031    import org.apache.oozie.service.SLAStoreService;
032    import org.apache.oozie.service.Services;
033    import org.apache.oozie.store.SLAStore;
034    import org.apache.oozie.store.StoreException;
035    import org.apache.oozie.util.XLog;
036    import org.apache.oozie.util.XmlUtils;
037    import org.jdom.Element;
038    import org.jdom.JDOMException;
039    
040    public class SLAServlet extends JsonRestServlet {
041        private static final String INSTRUMENTATION_NAME = "sla";
042    
043        private static final JsonRestServlet.ResourceInfo RESOURCES_INFO[] = new JsonRestServlet.ResourceInfo[1];
044    
045        static {
046            RESOURCES_INFO[0] = new JsonRestServlet.ResourceInfo("", Arrays
047                    .asList("GET"), Arrays.asList(
048                    new JsonRestServlet.ParameterInfo(
049                            RestConstants.SLA_GT_SEQUENCE_ID, String.class, true,
050                            Arrays.asList("GET")),
051                    new JsonRestServlet.ParameterInfo(RestConstants.MAX_EVENTS,
052                                                      String.class, false, Arrays.asList("GET"))));
053        }
054    
055        public SLAServlet() {
056            super(INSTRUMENTATION_NAME, RESOURCES_INFO);
057        }
058    
059        /**
060         * Return information about SLA Events.
061         */
062        @SuppressWarnings("unchecked")
063        public void doGet(HttpServletRequest request, HttpServletResponse response)
064                throws ServletException, IOException {
065    
066            try {
067                String gtSequenceNum = request
068                        .getParameter(RestConstants.SLA_GT_SEQUENCE_ID);
069                String strMaxEvents = request
070                        .getParameter(RestConstants.MAX_EVENTS);
071                int maxNoEvents = 100; // Default
072                XLog.getLog(getClass()).debug(
073                        "Got SLA GET request for :" + gtSequenceNum
074                                + " and max-events :" + strMaxEvents);
075                if (strMaxEvents != null && strMaxEvents.length() > 0) {
076                    maxNoEvents = Integer.parseInt(strMaxEvents);
077                }
078                if (gtSequenceNum != null) {
079                    long seqId = Long.parseLong(gtSequenceNum);
080                    stopCron();
081                    SLAEventsCommand seCommand = new SLAEventsCommand(seqId, maxNoEvents);
082                    List<SLAEventBean> slaEvntList = seCommand.call();
083                    long lastSeqId = seCommand.getLastSeqId();
084    
085                    Element eResponse = new Element("sla-message");
086                    for (SLAEventBean event : slaEvntList) {
087                        eResponse.addContent(event.toXml());
088                    }
089                    Element eLastSeq = new Element("last-sequence-id");
090                    eLastSeq.addContent(String.valueOf(lastSeqId));
091                    eResponse.addContent(eLastSeq);
092                    response.setContentType(XML_UTF8);
093                    XLog.getLog(getClass()).debug("Writing back SLA Servlet  Caller with last-seq-id " + lastSeqId);
094                    startCron();
095                    response.setStatus(HttpServletResponse.SC_OK);
096                    response.getWriter().write(
097                            XmlUtils.prettyPrint(eResponse) + "\n");
098                }
099                else {
100                    XLog.getLog(getClass()).error(
101                            "Not implemented witout gt_seq_id");
102                    throw new XServletException(HttpServletResponse.SC_BAD_REQUEST,
103                                                ErrorCode.E0401, "Not implemented without gtSeqID");
104                }
105            }
106            catch (CommandException ce) {
107                ce.printStackTrace();
108                XLog.getLog(getClass()).error("Command exception ", ce);
109                throw new XServletException(HttpServletResponse.SC_BAD_REQUEST, ce);
110            }
111            catch (RuntimeException re) {
112                re.printStackTrace();
113                XLog.getLog(getClass()).error("Runtime error ", re);
114                throw new XServletException(HttpServletResponse.SC_BAD_REQUEST, ErrorCode.E0307, re.getMessage());
115            }
116        }
117    
118    }