/*
* This library is part of OpenCms -
* the Open Source Content Management System
*
* Copyright (c) Alkacon Software GmbH (http://www.alkacon.com)
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* For further information about Alkacon Software, please see the
* company website: http://www.alkacon.com
*
* For further information about OpenCms, please see the
* project website: http://www.opencms.org
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
package org.opencms.loader;
import org.opencms.cache.CmsVfsNameBasedDiskCache;
import org.opencms.configuration.CmsParameterConfiguration;
import org.opencms.file.CmsFile;
import org.opencms.file.CmsObject;
import org.opencms.file.CmsResource;
import org.opencms.main.CmsEvent;
import org.opencms.main.CmsException;
import org.opencms.main.CmsLog;
import org.opencms.main.I_CmsEventListener;
import org.opencms.main.OpenCms;
import org.opencms.scheduler.jobs.CmsImageCacheCleanupJob;
import org.opencms.util.CmsStringUtil;
import java.io.IOException;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.logging.Log;
/**
* Loader for images from the OpenCms VSF with integrated image scaling and processing capabilities.<p>
*
* To scale or process an image, the parameter <code>{@link org.opencms.loader.CmsImageScaler#PARAM_SCALE}</code>
* has to be appended to the image URI. The value for the parameter needs to be composed from the <code>SCALE_PARAM</code>
* options provided by the constants in the <code>{@link org.opencms.file.types.CmsResourceTypeImage}</code> class.<p>
*
* For example, to scale an image to exact 800x600 pixel with center fitting and a background color of grey,
* the following parameter String can be used: <code>w:800,h:600,t:0,c:c0c0c0</code>.<p>
*
* @since 6.2.0
*/
public class CmsImageLoader extends CmsDumpLoader implements I_CmsEventListener {
/** The configuration parameter for the OpenCms XML configuration to set the image down scale operation. */
public static final String CONFIGURATION_DOWNSCALE = "image.scaling.downscale";
/** The configuration parameter for the OpenCms XML configuration to set the image cache repository. */
public static final String CONFIGURATION_IMAGE_FOLDER = "image.folder";
/** The configuration parameter for the OpenCms XML configuration to set the maximum image blur size. */
public static final String CONFIGURATION_MAX_BLUR_SIZE = "image.scaling.maxblursize";
/** The configuration parameter for the OpenCms XML configuration to set the maximum image scale size. */
public static final String CONFIGURATION_MAX_SCALE_SIZE = "image.scaling.maxsize";
/** The configuration parameter for the OpenCms XML configuration to enable the image scaling. */
public static final String CONFIGURATION_SCALING_ENABLED = "image.scaling.enabled";
/** Default name for the image cache repository. */
public static final String IMAGE_REPOSITORY_DEFAULT = "/WEB-INF/imagecache/";
/** Clear event parameter. */
public static final String PARAM_CLEAR_IMAGES_CACHE = "_IMAGES_CACHE_";
/** The id of this loader. */
public static final int RESOURCE_LOADER_ID_IMAGE_LOADER = 2;
/** The log object for this class. */
protected static final Log LOG = CmsLog.getLog(CmsImageLoader.class);
/** The (optional) image down scale parameters for image write operations. */
protected static String m_downScaleParams;
/** Indicates if image scaling is active. */
protected static boolean m_enabled;
/** The maximum image size (width * height) to apply image blurring when down scaling (setting this to high may cause "out of memory" errors). */
protected static int m_maxBlurSize = CmsImageScaler.SCALE_DEFAULT_MAX_BLUR_SIZE;
/** The disk cache to use for saving scaled image versions. */
protected static CmsVfsNameBasedDiskCache m_vfsDiskCache;
/** The name of the configured image cache repository. */
protected String m_imageRepositoryFolder;
/** The maximum image size (width or height) to allow when up scaling an image using request parameters. */
protected int m_maxScaleSize = CmsImageScaler.SCALE_DEFAULT_MAX_SIZE;
/**
* Creates a new image loader.<p>
*/
public CmsImageLoader() {
super();
}
/**
* Returns the image down scale parameters,
* which is set with the {@link #CONFIGURATION_DOWNSCALE} configuration option.<p>
*
* If no down scale parameters have been set in the configuration, this will return <code>null</code>.
*
* @return the image down scale parameters
*/
public static String getDownScaleParams() {
return m_downScaleParams;
}
/**
* Returns the path of the image cache repository folder in the RFS,
* which is set with the {@link #CONFIGURATION_IMAGE_FOLDER} configuration option.<p>
*
* @return the path of the image cache repository folder in the RFS
*/
public static String getImageRepositoryPath() {
return m_vfsDiskCache.getRepositoryPath();
}
/**
* The maximum blur size for image re-scale operations,
* which is set with the {@link #CONFIGURATION_MAX_BLUR_SIZE} configuration option.<p>
*
* The default is 2500 * 2500 pixel.<p>
*
* @return the maximum blur size for image re-scale operations
*/
public static int getMaxBlurSize() {
return m_maxBlurSize;
}
/**
* Returns <code>true</code> if the image scaling and processing capabilities for the
* OpenCms VFS images have been enabled, <code>false</code> if not.<p>
*
* Image scaling is enabled by setting the loader parameter <code>image.scaling.enabled</code>
* to the value <code>true</code> in the configuration file <code>opencms-vfs.xml</code>.<p>
*
* Enabling image processing in OpenCms may require several additional configuration steps
* on the server running OpenCms, especially in UNIX systems. Here it is often required to have an X window server
* configured and accessible so that the required Java ImageIO operations work.
* Therefore the image scaling capabilities in OpenCms are disabled by default.<p>
*
* @return <code>true</code> if the image scaling and processing capabilities for the
* OpenCms VFS images have been enabled
*/
public static boolean isEnabled() {
return m_enabled;
}
/**
* @see org.opencms.configuration.I_CmsConfigurationParameterHandler#addConfigurationParameter(java.lang.String, java.lang.String)
*/
@Override
public void addConfigurationParameter(String paramName, String paramValue) {
if (CmsStringUtil.isNotEmpty(paramName) && CmsStringUtil.isNotEmpty(paramValue)) {
if (CONFIGURATION_SCALING_ENABLED.equals(paramName)) {
m_enabled = Boolean.valueOf(paramValue).booleanValue();
}
if (CONFIGURATION_IMAGE_FOLDER.equals(paramName)) {
m_imageRepositoryFolder = paramValue.trim();
}
if (CONFIGURATION_MAX_SCALE_SIZE.equals(paramName)) {
m_maxScaleSize = CmsStringUtil.getIntValue(paramValue, CmsImageScaler.SCALE_DEFAULT_MAX_SIZE, paramName);
}
if (CONFIGURATION_MAX_BLUR_SIZE.equals(paramName)) {
m_maxBlurSize = CmsStringUtil.getIntValue(
paramValue,
CmsImageScaler.SCALE_DEFAULT_MAX_BLUR_SIZE,
paramName);
}
if (CONFIGURATION_DOWNSCALE.equals(paramName)) {
m_downScaleParams = paramValue.trim();
}
}
super.addConfigurationParameter(paramName, paramValue);
}
/**
* @see org.opencms.main.I_CmsEventListener#cmsEvent(org.opencms.main.CmsEvent)
*/
public void cmsEvent(CmsEvent event) {
if (event == null) {
return;
}
// only react on the clear caches event
int type = event.getType();
if (type != I_CmsEventListener.EVENT_CLEAR_CACHES) {
return;
}
// only react if the clear images cache parameter is set
Map<String, ?> data = event.getData();
if (data == null) {
return;
}
Object param = data.get(PARAM_CLEAR_IMAGES_CACHE);
if (param == null) {
return;
}
float age = -1;
if (param instanceof String) {
age = Float.valueOf((String)param).floatValue();
} else if (param instanceof Number) {
age = ((Number)param).floatValue();
}
CmsImageCacheCleanupJob.cleanImageCache(age);
}
/**
* @see org.opencms.loader.I_CmsResourceLoader#destroy()
*/
@Override
public void destroy() {
m_enabled = false;
m_imageRepositoryFolder = null;
m_vfsDiskCache = null;
}
/**
* @see org.opencms.configuration.I_CmsConfigurationParameterHandler#getConfiguration()
*/
@Override
public CmsParameterConfiguration getConfiguration() {
CmsParameterConfiguration result = new CmsParameterConfiguration();
CmsParameterConfiguration config = super.getConfiguration();
if (config != null) {
result.putAll(config);
}
result.put(CONFIGURATION_SCALING_ENABLED, String.valueOf(m_enabled));
result.put(CONFIGURATION_IMAGE_FOLDER, m_imageRepositoryFolder);
return result;
}
/**
* @see org.opencms.loader.I_CmsResourceLoader#getLoaderId()
*/
@Override
public int getLoaderId() {
return RESOURCE_LOADER_ID_IMAGE_LOADER;
}
/**
* @see org.opencms.configuration.I_CmsConfigurationParameterHandler#initConfiguration()
*/
@Override
public void initConfiguration() {
if (CmsStringUtil.isEmpty(m_imageRepositoryFolder)) {
m_imageRepositoryFolder = IMAGE_REPOSITORY_DEFAULT;
}
// initialize the image cache
if (m_vfsDiskCache == null) {
m_vfsDiskCache = new CmsVfsNameBasedDiskCache(
OpenCms.getSystemInfo().getWebApplicationRfsPath(),
m_imageRepositoryFolder);
}
OpenCms.addCmsEventListener(this);
// output setup information
if (CmsLog.INIT.isInfoEnabled()) {
CmsLog.INIT.info(Messages.get().getBundle().key(
Messages.INIT_IMAGE_REPOSITORY_PATH_1,
m_vfsDiskCache.getRepositoryPath()));
CmsLog.INIT.info(Messages.get().getBundle().key(
Messages.INIT_IMAGE_SCALING_ENABLED_1,
Boolean.valueOf(m_enabled)));
}
}
/**
* @see org.opencms.loader.I_CmsResourceLoader#load(org.opencms.file.CmsObject, org.opencms.file.CmsResource, javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
*/
@Override
public void load(CmsObject cms, CmsResource resource, HttpServletRequest req, HttpServletResponse res)
throws IOException, CmsException {
if (m_enabled) {
if (canSendLastModifiedHeader(resource, req, res)) {
// no image processing required at all
return;
}
// get the scale information from the request
CmsImageScaler scaler = new CmsImageScaler(req, m_maxScaleSize, m_maxBlurSize);
// load the file from the cache
CmsFile file = getScaledImage(cms, resource, scaler);
// now perform standard load operation inherited from dump loader
super.load(cms, file, req, res);
} else {
// scaling is disabled
super.load(cms, resource, req, res);
}
}
/**
* Returns a scaled version of the given OpenCms VFS image resource.<p>
*
* All results are cached in disk.
* If the scaled version does not exist in the cache, it is created.
* Unscaled versions of the images are also stored in the cache.<p>
*
* @param cms the current users OpenCms context
* @param resource the base VFS resource for the image
* @param scaler the configured image scaler
*
* @return a scaled version of the given OpenCms VFS image resource
*
* @throws IOException in case of errors accessing the disk based cache
* @throws CmsException in case of errors accessing the OpenCms VFS
*/
protected CmsFile getScaledImage(CmsObject cms, CmsResource resource, CmsImageScaler scaler)
throws IOException, CmsException {
String cacheParam = scaler.isValid() ? scaler.toString() : null;
String cacheName = m_vfsDiskCache.getCacheName(resource, cacheParam);
byte[] content = m_vfsDiskCache.getCacheContent(cacheName);
CmsFile file;
if (content != null) {
if (resource instanceof CmsFile) {
// the original file content must be modified (required e.g. for static export)
file = (CmsFile)resource;
} else {
// this is no file, but we don't want to use "upgrade" since we don't need to read the content from the VFS
file = new CmsFile(resource);
}
// save the content in the file
file.setContents(content);
} else {
// we must read the content from the VFS (if this has not been done yet)
file = cms.readFile(resource);
// upgrade the file (load the content)
if (scaler.isValid()) {
// valid scaling parameters found, scale the content
content = scaler.scaleImage(file);
// exchange the content of the file with the scaled version
file.setContents(content);
}
// save the file content in the cache
m_vfsDiskCache.saveCacheFile(cacheName, file.getContents());
}
return file;
}
}