001/*
002 * (C) Copyright 2010 Nuxeo SAS (http://nuxeo.com/) and contributors.
003 *
004 * All rights reserved. This program and the accompanying materials
005 * are made available under the terms of the GNU Lesser General Public License
006 * (LGPL) version 2.1 which accompanies this distribution, and is available at
007 * http://www.gnu.org/licenses/lgpl.html
008 *
009 * This library is distributed in the hope that it will be useful,
010 * but WITHOUT ANY WARRANTY; without even the implied warranty of
011 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
012 * Lesser General Public License for more details.
013 *
014 * Contributors:
015 *     Olivier Grisel
016 */
017package org.nuxeo.ecm.platform.categorization.listener;
018
019import java.util.ArrayList;
020import java.util.Arrays;
021import java.util.HashSet;
022import java.util.LinkedHashSet;
023import java.util.List;
024import java.util.Set;
025
026import org.apache.commons.logging.Log;
027import org.apache.commons.logging.LogFactory;
028import org.nuxeo.common.collections.ScopeType;
029import org.nuxeo.common.collections.ScopedMap;
030import org.nuxeo.ecm.core.api.CoreSession;
031import org.nuxeo.ecm.core.api.DocumentModel;
032import org.nuxeo.ecm.core.api.event.DocumentEventTypes;
033import org.nuxeo.ecm.core.event.Event;
034import org.nuxeo.ecm.core.event.EventBundle;
035import org.nuxeo.ecm.core.event.EventContext;
036import org.nuxeo.ecm.core.event.PostCommitEventListener;
037import org.nuxeo.ecm.core.event.impl.DocumentEventContext;
038import org.nuxeo.ecm.platform.categorization.service.DocumentCategorizationService;
039import org.nuxeo.runtime.api.Framework;
040
041/**
042 * Base default implementation of an asynchronous event listener that runs the document categorization service.
043 *
044 * @author ogrisel@nuxeo.com
045 */
046public class DocumentCategorizationAsyncListener implements PostCommitEventListener {
047
048    protected static final Log log = LogFactory.getLog(DocumentCategorizationAsyncListener.class);
049
050    protected static final String ALLREADY_CATEGORIZED_FLAG = DocumentCategorizationAsyncListener.class.getName();
051
052    // to be overridden in derived classes
053    protected Set<String> eventNames = new HashSet<String>(Arrays.asList(DocumentEventTypes.DOCUMENT_CREATED,
054            DocumentEventTypes.DOCUMENT_UPDATED));
055
056    protected DocumentCategorizationService service;
057
058    public void handleEvent(EventBundle events) {
059        // collect ids of documents to analyze while filtering duplicated doc
060        // ids
061        Set<DocumentModel> collectedDocuments = new LinkedHashSet<DocumentModel>(events.size());
062        for (Event event : events) {
063            if (!eventNames.contains(event.getName())) {
064                continue;
065            }
066            EventContext ctx = event.getContext();
067            if (ctx.hasProperty(ALLREADY_CATEGORIZED_FLAG)) {
068                // avoid infinite loops with event listeners triggering them
069                // selves on the same documents
070                continue;
071            }
072            if (ctx instanceof DocumentEventContext) {
073                DocumentEventContext docCtx = (DocumentEventContext) ctx;
074                DocumentModel doc = docCtx.getSourceDocument();
075                if (doc != null) {
076                    ScopedMap contextData = doc.getContextData();
077                    contextData.putScopedValue(ScopeType.REQUEST, ALLREADY_CATEGORIZED_FLAG, Boolean.TRUE);
078                    collectedDocuments.add(doc);
079                }
080            }
081        }
082        if (!collectedDocuments.isEmpty()) {
083            // assume all document stem from the same repo, with the
084            // save session
085            CoreSession session = collectedDocuments.iterator().next().getCoreSession();
086            DocumentCategorizationService categorizationService = Framework.getService(
087                    DocumentCategorizationService.class);
088            List<DocumentModel> documents = categorizationService.updateCategories(
089                    new ArrayList<DocumentModel>(collectedDocuments));
090            if (!documents.isEmpty()) {
091                session.saveDocuments(documents.toArray(new DocumentModel[documents.size()]));
092                session.save();
093            }
094        }
095    }
096
097}