Source code

001/*
002 * This library is part of OpenCms -
003 * the Open Source Content Management System
004 *
005 * Copyright (c) Alkacon Software GmbH & Co. KG (https://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: https://www.alkacon.com
019 *
020 * For further information about OpenCms, please see the
021 * project website: https://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.loader;
029
030import org.opencms.ade.galleries.CmsPreviewService;
031import org.opencms.cache.CmsVfsNameBasedDiskCache;
032import org.opencms.configuration.CmsParameterConfiguration;
033import org.opencms.file.CmsFile;
034import org.opencms.file.CmsObject;
035import org.opencms.file.CmsResource;
036import org.opencms.main.CmsEvent;
037import org.opencms.main.CmsException;
038import org.opencms.main.CmsLog;
039import org.opencms.main.I_CmsEventListener;
040import org.opencms.main.OpenCms;
041import org.opencms.scheduler.jobs.CmsImageCacheCleanupJob;
042import org.opencms.util.CmsStringUtil;
043
044import java.io.IOException;
045import java.util.Map;
046
047import javax.servlet.http.HttpServletRequest;
048import javax.servlet.http.HttpServletResponse;
049
050import org.apache.commons.logging.Log;
051
052/**
053 * Loader for images from the OpenCms VSF with integrated image scaling and processing capabilities.<p>
054 *
055 * To scale or process an image, the parameter <code>{@link org.opencms.loader.CmsImageScaler#PARAM_SCALE}</code>
056 * has to be appended to the image URI. The value for the parameter needs to be composed from the <code>SCALE_PARAM</code>
057 * options provided by the constants in the <code>{@link org.opencms.file.types.CmsResourceTypeImage}</code> class.<p>
058 *
059 * For example, to scale an image to exact 800x600 pixel with center fitting and a background color of grey,
060 * the following parameter String can be used: <code>w:800,h:600,t:0,c:c0c0c0</code>.<p>
061 *
062 * @since 6.2.0
063 */
064public class CmsImageLoader extends CmsDumpLoader implements I_CmsEventListener {
065
066    /** Controls max number of threads that are allowed to scale images concurrently. */
067    public static final String CONFIGURATION_CONCURRENCY = "image.scaling.concurrency";
068
069    /** The configuration parameter for the OpenCms XML configuration to set the image down scale operation. */
070    public static final String CONFIGURATION_DOWNSCALE = "image.scaling.downscale";
071
072    /** The configuration parameter for the OpenCms XML configuration to set the image cache repository. */
073    public static final String CONFIGURATION_IMAGE_FOLDER = "image.folder";
074
075    /** The configuration parameter for the OpenCms XML configuration to set the maximum image blur size. */
076    public static final String CONFIGURATION_MAX_BLUR_SIZE = "image.scaling.maxblursize";
077
078    /** The configuration parameter for the OpenCms XML configuration to set the maximum image scale size. */
079    public static final String CONFIGURATION_MAX_SCALE_SIZE = "image.scaling.maxsize";
080
081    /** The configuration parameter for the OpenCms XML configuration to enable the image scaling. */
082    public static final String CONFIGURATION_SCALING_ENABLED = "image.scaling.enabled";
083
084    /** Default name for the image cache repository. */
085    public static final String IMAGE_REPOSITORY_DEFAULT = "/WEB-INF/imagecache/";
086
087    /** Clear event parameter. */
088    public static final String PARAM_CLEAR_IMAGES_CACHE = "_IMAGES_CACHE_";
089
090    /** The id of this loader. */
091    public static final int RESOURCE_LOADER_ID_IMAGE_LOADER = 2;
092
093    /** The log object for this class. */
094    protected static final Log LOG = CmsLog.getLog(CmsImageLoader.class);
095
096    /** The (optional) image down scale parameters for image write operations. */
097    protected static String m_downScaleParams;
098
099    /** Indicates if image scaling is active. */
100    protected static boolean m_enabled;
101
102    /** The maximum image size (width * height) to apply image blurring when down scaling (setting this to high may cause "out of memory" errors). */
103    protected static int m_maxBlurSize = CmsImageScaler.SCALE_DEFAULT_MAX_BLUR_SIZE;
104
105    /** The disk cache to use for saving scaled image versions. */
106    protected static CmsVfsNameBasedDiskCache m_vfsDiskCache;
107
108    /** The name of the configured image cache repository. */
109    protected String m_imageRepositoryFolder;
110
111    /** The maximum image size (width or height) to allow when up scaling an image using request parameters. */
112    protected int m_maxScaleSize = CmsImageScaler.SCALE_DEFAULT_MAX_SIZE;
113
114    /**
115     * Creates a new image loader.<p>
116     */
117    public CmsImageLoader() {
118
119        super();
120    }
121
122    /**
123     * Returns the image down scale parameters,
124     * which is set with the {@link #CONFIGURATION_DOWNSCALE} configuration option.<p>
125     *
126     * If no down scale parameters have been set in the configuration, this will return <code>null</code>.
127     *
128     * @return the image down scale parameters
129     */
130    public static String getDownScaleParams() {
131
132        return m_downScaleParams;
133    }
134
135    /**
136     * Returns the path of the image cache repository folder in the RFS,
137     * which is set with the {@link #CONFIGURATION_IMAGE_FOLDER} configuration option.<p>
138     *
139     * @return the path of the image cache repository folder in the RFS
140     */
141    public static String getImageRepositoryPath() {
142
143        return m_vfsDiskCache.getRepositoryPath();
144    }
145
146    /**
147     * The maximum blur size for image re-scale operations,
148     * which is set with the {@link #CONFIGURATION_MAX_BLUR_SIZE} configuration option.<p>
149     *
150     * The default is 2500 * 2500 pixel.<p>
151     *
152     * @return the maximum blur size for image re-scale operations
153     */
154    public static int getMaxBlurSize() {
155
156        return m_maxBlurSize;
157    }
158
159    /**
160     * Returns <code>true</code> if the image scaling and processing capabilities for the
161     * OpenCms VFS images have been enabled, <code>false</code> if not.<p>
162     *
163     * Image scaling is enabled by setting the loader parameter <code>image.scaling.enabled</code>
164     * to the value <code>true</code> in the configuration file <code>opencms-vfs.xml</code>.<p>
165     *
166     * Enabling image processing in OpenCms may require several additional configuration steps
167     * on the server running OpenCms, especially in UNIX systems. Here it is often required to have an X window server
168     * configured and accessible so that the required Java ImageIO operations work.
169     * Therefore the image scaling capabilities in OpenCms are disabled by default.<p>
170     *
171     * @return <code>true</code> if the image scaling and processing capabilities for the
172     *      OpenCms VFS images have been enabled
173     */
174    public static boolean isEnabled() {
175
176        return m_enabled;
177    }
178
179    /**
180     * @see org.opencms.configuration.I_CmsConfigurationParameterHandler#addConfigurationParameter(java.lang.String, java.lang.String)
181     */
182    @Override
183    public void addConfigurationParameter(String paramName, String paramValue) {
184
185        if (CmsStringUtil.isNotEmpty(paramName) && CmsStringUtil.isNotEmpty(paramValue)) {
186            if (CONFIGURATION_SCALING_ENABLED.equals(paramName)) {
187                m_enabled = Boolean.valueOf(paramValue).booleanValue();
188            }
189            if (CONFIGURATION_IMAGE_FOLDER.equals(paramName)) {
190                m_imageRepositoryFolder = paramValue.trim();
191            }
192            if (CONFIGURATION_MAX_SCALE_SIZE.equals(paramName)) {
193                m_maxScaleSize = CmsStringUtil.getIntValue(
194                    paramValue,
195                    CmsImageScaler.SCALE_DEFAULT_MAX_SIZE,
196                    paramName);
197            }
198            if (CONFIGURATION_MAX_BLUR_SIZE.equals(paramName)) {
199                m_maxBlurSize = CmsStringUtil.getIntValue(
200                    paramValue,
201                    CmsImageScaler.SCALE_DEFAULT_MAX_BLUR_SIZE,
202                    paramName);
203            }
204            if (CONFIGURATION_DOWNSCALE.equals(paramName)) {
205                m_downScaleParams = paramValue.trim();
206            }
207
208            if (CONFIGURATION_CONCURRENCY.equals(paramName)) {
209                int concurrency = CmsStringUtil.getIntValue(paramValue, CmsImageScaler.DEFAULT_CONCURRENCY, paramName);
210                if (concurrency > 0) {
211                    CmsImageScaler.setConcurrency(concurrency);
212                }
213            }
214        }
215        super.addConfigurationParameter(paramName, paramValue);
216    }
217
218    /**
219     * @see org.opencms.main.I_CmsEventListener#cmsEvent(org.opencms.main.CmsEvent)
220     */
221    public void cmsEvent(CmsEvent event) {
222
223        if (event == null) {
224            return;
225        }
226        // only react on the clear caches event
227        int type = event.getType();
228        if (type != I_CmsEventListener.EVENT_CLEAR_CACHES) {
229            return;
230        }
231        // only react if the clear images cache parameter is set
232        Map<String, ?> data = event.getData();
233        if (data == null) {
234            return;
235        }
236        Object param = data.get(PARAM_CLEAR_IMAGES_CACHE);
237        if (param == null) {
238            return;
239        }
240        float age = -1;
241        if (param instanceof String) {
242            age = Float.valueOf((String)param).floatValue();
243        } else if (param instanceof Number) {
244            age = ((Number)param).floatValue();
245        }
246        CmsImageCacheCleanupJob.cleanImageCache(age);
247    }
248
249    /**
250     * @see org.opencms.loader.I_CmsResourceLoader#destroy()
251     */
252    @Override
253    public void destroy() {
254
255        m_enabled = false;
256        m_imageRepositoryFolder = null;
257        m_vfsDiskCache = null;
258    }
259
260    /**
261     * @see org.opencms.configuration.I_CmsConfigurationParameterHandler#getConfiguration()
262     */
263    @Override
264    public CmsParameterConfiguration getConfiguration() {
265
266        CmsParameterConfiguration result = new CmsParameterConfiguration();
267        CmsParameterConfiguration config = super.getConfiguration();
268        if (config != null) {
269            result.putAll(config);
270        }
271        result.put(CONFIGURATION_SCALING_ENABLED, String.valueOf(m_enabled));
272        result.put(CONFIGURATION_IMAGE_FOLDER, m_imageRepositoryFolder);
273        return result;
274    }
275
276    /**
277     * @see org.opencms.loader.I_CmsResourceLoader#getLoaderId()
278     */
279    @Override
280    public int getLoaderId() {
281
282        return RESOURCE_LOADER_ID_IMAGE_LOADER;
283    }
284
285    /**
286     * @see org.opencms.configuration.I_CmsConfigurationParameterHandler#initConfiguration()
287     */
288    @Override
289    public void initConfiguration() {
290
291        if (CmsStringUtil.isEmpty(m_imageRepositoryFolder)) {
292            m_imageRepositoryFolder = IMAGE_REPOSITORY_DEFAULT;
293        }
294        // initialize the image cache
295        if (m_vfsDiskCache == null) {
296            m_vfsDiskCache = new CmsVfsNameBasedDiskCache(
297                OpenCms.getSystemInfo().getWebApplicationRfsPath(),
298                m_imageRepositoryFolder);
299        }
300        OpenCms.addCmsEventListener(this);
301        // output setup information
302        if (CmsLog.INIT.isInfoEnabled()) {
303            CmsLog.INIT.info(
304                Messages.get().getBundle().key(
305                    Messages.INIT_IMAGE_REPOSITORY_PATH_1,
306                    m_vfsDiskCache.getRepositoryPath()));
307            CmsLog.INIT.info(
308                Messages.get().getBundle().key(Messages.INIT_IMAGE_SCALING_ENABLED_1, Boolean.valueOf(m_enabled)));
309        }
310    }
311
312    /**
313     * @see org.opencms.loader.I_CmsResourceLoader#load(org.opencms.file.CmsObject, org.opencms.file.CmsResource, javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
314     */
315    @Override
316    public void load(CmsObject cms, CmsResource resource, HttpServletRequest req, HttpServletResponse res)
317    throws IOException, CmsException {
318
319        if (m_enabled) {
320            if (canSendLastModifiedHeader(resource, req, res)) {
321                // no image processing required at all
322                return;
323            }
324            // get the scale information from the request
325            CmsImageScaler scaler = new CmsImageScaler(req, m_maxScaleSize, m_maxBlurSize);
326            // load the file from the cache
327            CmsFile file = getScaledImage(cms, resource, scaler);
328            // now perform standard load operation inherited from dump loader
329            super.load(cms, file, req, res);
330        } else {
331            // scaling is disabled
332            super.load(cms, resource, req, res);
333        }
334    }
335
336    /**
337     * Returns a scaled version of the given OpenCms VFS image resource.<p>
338     *
339     * All results are cached in disk.
340     * If the scaled version does not exist in the cache, it is created.
341     * Unscaled versions of the images are also stored in the cache.<p>
342     *
343     * @param cms the current users OpenCms context
344     * @param resource the base VFS resource for the image
345     * @param scaler the configured image scaler
346     *
347     * @return a scaled version of the given OpenCms VFS image resource
348     *
349     * @throws IOException in case of errors accessing the disk based cache
350     * @throws CmsException in case of errors accessing the OpenCms VFS
351     */
352    protected CmsFile getScaledImage(CmsObject cms, CmsResource resource, CmsImageScaler scaler)
353    throws IOException, CmsException {
354
355        String cacheParam = scaler.isValid() ? scaler.toString() : null;
356        String cacheName = m_vfsDiskCache.getCacheName(resource, cacheParam);
357        byte[] content = m_vfsDiskCache.getCacheContent(cacheName);
358
359        CmsFile file;
360        if (content != null) {
361            if (resource instanceof CmsFile) {
362                // the original file content must be modified (required e.g. for static export)
363                file = (CmsFile)resource;
364            } else {
365                // this is no file, but we don't want to use "upgrade" since we don't need to read the content from the VFS
366                file = new CmsFile(resource);
367            }
368            // save the content in the file
369            file.setContents(content);
370        } else {
371            // we must read the content from the VFS (if this has not been done yet)
372            file = cms.readFile(resource);
373            // upgrade the file (load the content)
374            if (scaler.isValid()) {
375                if (scaler.getType() == 8) {
376                    // only need the focal point for mode 8
377                    scaler.setFocalPoint(CmsPreviewService.readFocalPoint(cms, resource));
378                }
379                // valid scaling parameters found, scale the content
380                content = scaler.scaleImage(file);
381                // exchange the content of the file with the scaled version
382                file.setContents(content);
383            }
384            // save the file content in the cache
385            m_vfsDiskCache.saveCacheFile(cacheName, file.getContents());
386        }
387        return file;
388    }
389}