Source code

001/*
002 * This library is part of OpenCms -
003 * the Open Source Content Management System
004 *
005 * Copyright (c) Alkacon Software GmbH (http://www.alkacon.com)
006 *
007 * This library is free software; you can redistribute it and/or
008 * modify it under the terms of the GNU Lesser General Public
009 * License as published by the Free Software Foundation; either
010 * version 2.1 of the License, or (at your option) any later version.
011 *
012 * This library is distributed in the hope that it will be useful,
013 * but WITHOUT ANY WARRANTY; without even the implied warranty of
014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
015 * Lesser General Public License for more details.
016 *
017 * For further information about Alkacon Software, please see the
018 * company website: http://www.alkacon.com
019 *
020 * For further information about OpenCms, please see the
021 * project website: http://www.opencms.org
022 *
023 * You should have received a copy of the GNU Lesser General Public
024 * License along with this library; if not, write to the Free Software
025 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
026 */
027
028package org.opencms.gwt;
029
030import org.opencms.db.CmsDriverManager;
031import org.opencms.file.CmsObject;
032import org.opencms.file.CmsResource;
033import org.opencms.main.CmsEvent;
034import org.opencms.main.CmsLog;
035import org.opencms.main.I_CmsEventListener;
036import org.opencms.main.OpenCms;
037import org.opencms.util.CmsCollectionsGenericWrapper;
038import org.opencms.util.CmsStringUtil;
039
040import java.io.ByteArrayInputStream;
041import java.io.File;
042import java.io.FileInputStream;
043import java.io.IOException;
044import java.io.InputStream;
045import java.net.MalformedURLException;
046import java.net.URL;
047import java.text.ParseException;
048import java.util.List;
049
050import org.apache.commons.logging.Log;
051
052import com.google.gwt.user.server.rpc.SerializationPolicy;
053import com.google.gwt.user.server.rpc.SerializationPolicyLoader;
054
055/**
056 * This class contains the data that should be cached for a specific service class.<p>
057 *
058 * We cache instances of this class rather than caching instances of {@link CmsGwtService} directly because
059 * its superclass, {@link com.google.gwt.user.server.rpc.RemoteServiceServlet}, does some caching which we can't use because it doesn't
060 * take the distinction between online and offline requests into account.
061 *
062 * @since 8.0.0
063 *
064 */
065public class CmsGwtServiceContext implements I_CmsEventListener {
066
067    /** The static log object for this class. */
068    private static final Log LOG = CmsLog.getLog(CmsGwtServiceContext.class);
069
070    /** The name, which is used for debugging. */
071    private String m_name;
072
073    /** The serialization policy path. */
074    private String m_serializationPolicyPath;
075
076    /** The offline serialization policy. */
077    private SerializationPolicy m_serPolicyOffline;
078
079    /** The online serialization policy. */
080    private SerializationPolicy m_serPolicyOnline;
081
082    /**
083     * Creates a new service context object.<p>
084     *
085     * @param name an identifier which is used for debugging
086     */
087    public CmsGwtServiceContext(String name) {
088
089        m_name = name;
090
091        // listen on VFS changes for serialization policies
092        OpenCms.addCmsEventListener(
093            this,
094            new int[] {
095                I_CmsEventListener.EVENT_RESOURCE_AND_PROPERTIES_MODIFIED,
096                I_CmsEventListener.EVENT_RESOURCES_AND_PROPERTIES_MODIFIED,
097                I_CmsEventListener.EVENT_RESOURCE_MODIFIED,
098                I_CmsEventListener.EVENT_RESOURCES_MODIFIED,
099                I_CmsEventListener.EVENT_RESOURCE_DELETED,
100                I_CmsEventListener.EVENT_PUBLISH_PROJECT,
101                I_CmsEventListener.EVENT_CLEAR_CACHES,
102                I_CmsEventListener.EVENT_CLEAR_ONLINE_CACHES,
103                I_CmsEventListener.EVENT_CLEAR_OFFLINE_CACHES});
104
105    }
106
107    /**
108     * @see org.opencms.main.I_CmsEventListener#cmsEvent(org.opencms.main.CmsEvent)
109     */
110    public void cmsEvent(CmsEvent event) {
111
112        CmsResource resource = null;
113        List<CmsResource> resources = null;
114
115        switch (event.getType()) {
116            case I_CmsEventListener.EVENT_RESOURCE_AND_PROPERTIES_MODIFIED:
117            case I_CmsEventListener.EVENT_RESOURCE_MODIFIED:
118                Object change = event.getData().get(I_CmsEventListener.KEY_CHANGE);
119                if ((change != null) && change.equals(new Integer(CmsDriverManager.NOTHING_CHANGED))) {
120                    // skip lock & unlock
121                    return;
122                }
123                // a resource has been modified in a way that it *IS NOT* necessary also to clear
124                // lists of cached sub-resources where the specified resource might be contained inside.
125                resource = (CmsResource)event.getData().get(I_CmsEventListener.KEY_RESOURCE);
126                uncacheResource(resource);
127                break;
128
129            case I_CmsEventListener.EVENT_RESOURCES_AND_PROPERTIES_MODIFIED:
130                // a list of resources and all of their properties have been modified
131                resources = CmsCollectionsGenericWrapper.list(event.getData().get(I_CmsEventListener.KEY_RESOURCES));
132                uncacheResources(resources);
133                break;
134
135            case I_CmsEventListener.EVENT_RESOURCE_MOVED:
136            case I_CmsEventListener.EVENT_RESOURCE_DELETED:
137            case I_CmsEventListener.EVENT_RESOURCES_MODIFIED:
138                // a list of resources has been modified
139                resources = CmsCollectionsGenericWrapper.list(event.getData().get(I_CmsEventListener.KEY_RESOURCES));
140                uncacheResources(resources);
141                break;
142
143            case I_CmsEventListener.EVENT_CLEAR_ONLINE_CACHES:
144            case I_CmsEventListener.EVENT_PUBLISH_PROJECT:
145                m_serPolicyOnline = null;
146                break;
147
148            case I_CmsEventListener.EVENT_CLEAR_CACHES:
149                m_serPolicyOnline = null;
150                m_serPolicyOffline = null;
151                break;
152
153            case I_CmsEventListener.EVENT_CLEAR_OFFLINE_CACHES:
154                m_serPolicyOffline = null;
155                break;
156
157            default:
158                // noop
159                break;
160        }
161    }
162
163    /**
164     * @see java.lang.Object#toString()
165     */
166    @Override
167    public String toString() {
168
169        return super.toString() + "(" + m_name + ")";
170    }
171
172    /**
173     * Returns the serialization policy for the service.<p>
174     *
175     * @param cms the current CMS context
176     * @param moduleBaseURL the module's base URL
177     * @param strongName the strong name of the service
178     *
179     * @return the serialization policy for the given service
180     */
181    protected SerializationPolicy getSerializationPolicy(CmsObject cms, String moduleBaseURL, String strongName) {
182
183        if (m_serializationPolicyPath == null) {
184            m_serializationPolicyPath = getSerializationPolicyPath(moduleBaseURL, strongName);
185        }
186        return getSerializationPolicy(cms);
187    }
188
189    /**
190     * Finds the path of the serialization policy file.<p>
191     *
192     * @param moduleBaseURL the GWT module's base url
193     * @param strongName the strong name of the service
194     *
195     * @return the serialization policy path
196     */
197    protected String getSerializationPolicyPath(String moduleBaseURL, String strongName) {
198
199        // locate the serialization policy file in OpenCms
200        String modulePath = null;
201        try {
202            modulePath = new URL(moduleBaseURL).getPath();
203        } catch (MalformedURLException ex) {
204            // moduleBaseUrl is bad
205            LOG.error(ex.getLocalizedMessage(), ex);
206            return null;
207        } catch (NullPointerException ex) {
208            // moduleBaseUrl is null
209            LOG.error(ex.getLocalizedMessage(), ex);
210            return null;
211        }
212        return SerializationPolicyLoader.getSerializationPolicyFileName(modulePath + strongName);
213    }
214
215    /**
216     * Returns the serialization policy, using lazy initialization.<p>
217     *
218     * @param cms the current cms context
219     *
220     * @return the serialization policy
221     */
222    private SerializationPolicy getSerializationPolicy(CmsObject cms) {
223
224        boolean online = cms.getRequestContext().getCurrentProject().isOnlineProject();
225        if (online && (m_serPolicyOnline != null)) {
226            return m_serPolicyOnline;
227        } else if (!online && (m_serPolicyOffline != null)) {
228            return m_serPolicyOffline;
229        }
230
231        SerializationPolicy serializationPolicy = null;
232
233        // Open the RPC resource file and read its contents
234        InputStream is;
235        try {
236            // first try reading from the RFS
237            String rfsPath = m_serializationPolicyPath;
238
239            if (rfsPath.startsWith(OpenCms.getSystemInfo().getContextPath())) {
240                rfsPath = rfsPath.substring(OpenCms.getSystemInfo().getContextPath().length());
241            }
242            rfsPath = CmsStringUtil.joinPaths(OpenCms.getSystemInfo().getWebApplicationRfsPath(), rfsPath);
243            File policyFile = new File(rfsPath);
244            if (policyFile.exists() && policyFile.canRead()) {
245                is = new FileInputStream(policyFile);
246            } else {
247                // the file does not exist in the RFS, try the VFS
248                String policyPath = OpenCms.getLinkManager().getRootPath(cms, rfsPath);
249                is = new ByteArrayInputStream(cms.readFile(policyPath).getContents());
250            }
251        } catch (Exception ex) {
252            // most likely file not found
253            String message = "ERROR: The serialization policy file '"
254                + m_serializationPolicyPath
255                + "' was not found; did you forget to include it in this deployment?";
256            LOG.warn(message);
257            LOG.warn(ex.getLocalizedMessage(), ex);
258            return new CmsDummySerializationPolicy();
259        }
260
261        // read the policy
262        try {
263            serializationPolicy = SerializationPolicyLoader.loadFromStream(is, null);
264        } catch (ParseException e) {
265            LOG.error("ERROR: Failed to parse the policy file '" + m_serializationPolicyPath + "'", e);
266        } catch (IOException e) {
267            LOG.error("ERROR: Could not read the policy file '" + m_serializationPolicyPath + "'", e);
268        } finally {
269            try {
270                is.close();
271            } catch (IOException e) {
272                // Ignore this error
273            }
274        }
275
276        if (online) {
277            m_serPolicyOnline = serializationPolicy;
278        } else {
279            m_serPolicyOffline = serializationPolicy;
280        }
281        return serializationPolicy;
282    }
283
284    /**
285     * Removes a cached resource from the cache.<p>
286     *
287     * @param resource the resource
288     */
289    private void uncacheResource(CmsResource resource) {
290
291        if (resource == null) {
292            return;
293        }
294        if ((m_serializationPolicyPath != null) && resource.getRootPath().equals(m_serializationPolicyPath)) {
295            m_serPolicyOffline = null;
296        }
297    }
298
299    /**
300     * Removes a bunch of cached resources from the cache.<p>
301     *
302     * @param resources a list of resources
303     *
304     * @see #uncacheResource(CmsResource)
305     */
306    private void uncacheResources(List<CmsResource> resources) {
307
308        if (resources == null) {
309            return;
310        }
311        for (int i = 0, n = resources.size(); i < n; i++) {
312            // remove the resource
313            uncacheResource(resources.get(i));
314        }
315    }
316
317}