001/*
002 *  Copyright 2011 Anyware Services
003 *
004 *  Licensed under the Apache 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.apache.org/licenses/LICENSE-2.0
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 */
016
017package org.ametys.web.cache;
018
019import java.util.Map;
020import java.util.regex.Matcher;
021import java.util.regex.Pattern;
022
023import org.apache.avalon.framework.service.ServiceException;
024import org.apache.avalon.framework.service.ServiceManager;
025import org.apache.avalon.framework.service.Serviceable;
026
027import org.ametys.core.observation.Event;
028import org.ametys.core.observation.Observer;
029import org.ametys.core.util.FilenameUtils;
030import org.ametys.core.util.URIUtils;
031import org.ametys.plugins.explorer.ObservationConstants;
032import org.ametys.runtime.plugin.component.AbstractLogEnabled;
033
034/**
035 * {@link Observer} for listening resource changes in order to invalidate cache on front-office.
036 */
037public class InvalidateCacheOnResourceUpdateObserver extends AbstractLogEnabled implements Observer, Serviceable
038{
039    private static final Pattern __RESOURCE_PATTERN = Pattern.compile("^.*/ametys-internal:sites/([^/]+)/ametys-internal:resources/(.*)$");
040    private static final Pattern __ROOT_SITE_RESOURCE_PATTERN = Pattern.compile("^.*/ametys-internal:sites/[^/]+/[^/]+/([^/]+)/ametys-internal:resources/(.*)$");
041    private static final Pattern __SHARED_RESOURCE_PATTERN = Pattern.compile("^.*/ametys:plugins/web-explorer/shared-resources/(.*)$");
042    
043    private FOCommHelper _foCommHelper;
044    
045    public void service(ServiceManager manager) throws ServiceException
046    {
047        _foCommHelper = (FOCommHelper) manager.lookup(FOCommHelper.ROLE);
048    }
049    
050    public int getPriority()
051    {
052        return Observer.MAX_PRIORITY;
053    }
054    
055    public boolean supports(Event event)
056    {
057        String eventType = event.getId();
058        return eventType.equals(ObservationConstants.EVENT_RESOURCE_CREATED)
059                || eventType.equals(ObservationConstants.EVENT_RESOURCE_UPDATED)
060                || eventType.equals(ObservationConstants.EVENT_RESOURCE_DELETED)
061                || eventType.equals(ObservationConstants.EVENT_RESOURCE_MOVED)
062                || eventType.equals(ObservationConstants.EVENT_RESOURCE_RENAMED)
063                || eventType.equals(ObservationConstants.EVENT_COLLECTION_CREATED)
064                || eventType.equals(ObservationConstants.EVENT_COLLECTION_DELETED)
065                || eventType.equals(ObservationConstants.EVENT_COLLECTION_RENAMED)
066                || eventType.equals(ObservationConstants.EVENT_COLLECTION_MOVED);
067    }
068    
069    @Override
070    public void observe(Event event, Map<String, Object> transientVars) throws Exception
071    {
072        String eventType = event.getId();
073        
074        try
075        {
076            Map<String, Object> args = event.getArguments();
077            if (eventType.equals(ObservationConstants.EVENT_RESOURCE_CREATED))
078            {
079                // Multiple resources may have been created, look for to parent path
080                String path = (String) args.get(ObservationConstants.ARGS_PARENT_PATH);
081                _invalidate(path);
082            }
083            else if (eventType.equals(ObservationConstants.EVENT_RESOURCE_UPDATED) || eventType.equals(ObservationConstants.EVENT_RESOURCE_DELETED) || eventType.equals(ObservationConstants.EVENT_COLLECTION_DELETED))
084            {
085                String path = (String) args.get(ObservationConstants.ARGS_PATH);
086                _invalidate(path);
087            }
088            else if (eventType.equals(ObservationConstants.EVENT_RESOURCE_RENAMED) || eventType.equals(ObservationConstants.EVENT_COLLECTION_RENAMED) || eventType.equals(ObservationConstants.EVENT_RESOURCE_MOVED)  || eventType.equals(ObservationConstants.EVENT_COLLECTION_MOVED))
089            {
090                String oldPath = (String) args.get("object.old.path");
091                _invalidate(oldPath);
092            }
093        }
094        catch (Exception e)
095        {
096            getLogger().error("Exception while trying to handle explorer event + " + event, e);
097        }
098        
099    }
100    
101    private void _invalidate(String path) throws Exception
102    {
103        Matcher matcher1 = __RESOURCE_PATTERN.matcher(path);
104        Matcher matcher2 = __ROOT_SITE_RESOURCE_PATTERN.matcher(path);
105        Matcher sharedMatcher = __SHARED_RESOURCE_PATTERN.matcher(path);
106        
107        String site = null;
108        String pathInSite = null;
109        if (matcher1.matches())
110        {
111            site = matcher1.group(1);
112            pathInSite = matcher1.group(2);
113        }
114        else if (matcher2.matches())
115        {
116            site = matcher2.group(1);
117            pathInSite = matcher2.group(2);
118        }
119        else if (sharedMatcher.matches())
120        {
121            pathInSite = sharedMatcher.group(1);
122        }
123        else
124        {
125            getLogger().debug("{} does not match attempted pattern for resources of explorer", path);
126            return;
127        }
128        
129        // encode it twice, as it is stored in encoded form on FO side
130        String encodedPath = URIUtils.encodePath(FilenameUtils.encodePath(pathInSite));
131        
132        if (site != null)
133        {
134            _foCommHelper.testWS("/_invalidate-page/" + site + "/_resource/" + encodedPath);
135            _foCommHelper.testWS("/_invalidate-images/" + site + "/_resource/" + encodedPath);
136        }
137        else
138        {
139            _foCommHelper.testWS("/_invalidate-shared-resources/_shared-resource/" + encodedPath);
140            _foCommHelper.testWS("/_invalidate-shared-resources-images/_shared-resource/" + encodedPath);
141        }
142    }
143}