001 /*
002 * Copyright (C) 2012 eXo Platform SAS.
003 *
004 * This is free software; you can redistribute it and/or modify it
005 * under the terms of the GNU Lesser General Public License as
006 * published by the Free Software Foundation; either version 2.1 of
007 * the License, or (at your option) any later version.
008 *
009 * This software 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 * You should have received a copy of the GNU Lesser General Public
015 * License along with this software; if not, write to the Free
016 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
017 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
018 */
019
020 package org.crsh.plugin;
021
022 import org.crsh.util.ServletContextMap;
023 import org.crsh.util.Utils;
024 import org.crsh.vfs.spi.FSMountFactory;
025 import org.crsh.vfs.spi.file.FileMountFactory;
026 import org.crsh.vfs.spi.servlet.WarMountFactory;
027 import org.crsh.vfs.spi.url.ClassPathMountFactory;
028
029 import javax.servlet.ServletContext;
030 import javax.servlet.ServletContextEvent;
031 import javax.servlet.ServletContextListener;
032 import java.util.HashMap;
033 import java.util.Map;
034 import java.util.logging.Level;
035
036 public class WebPluginLifeCycle extends Embedded implements ServletContextListener {
037
038 /** . */
039 private static final Object lock = new Object();
040
041 /** . */
042 private static final Map<String, PluginContext> contextMap = new HashMap<String, PluginContext>();
043
044 /** . */
045 private boolean registered = false;
046
047 /** . */
048 private Map<String, FSMountFactory<?>> mountContexts = new HashMap<String, FSMountFactory<?>>(3);
049
050 /** . */
051 private ServletContext context;
052
053 /**
054 * Returns a plugin context associated with the servlet context or null if such context does not exist.
055 *
056 * @param contextPath the context path
057 * @return the associated plugin context
058 * @throws NullPointerException if the servlet context argument is null
059 */
060 public static PluginContext getPluginContext(String contextPath) throws NullPointerException {
061 synchronized (lock) {
062 return contextMap.get(contextPath);
063 }
064 }
065
066 /**
067 * This implementation register three file system drivers:
068 * <ul>
069 * <li><code>file</code> : the current file system</li>
070 * <li><code>classpath</code> : the classpath</li>
071 * <li><code>war</code> : the war content</li>
072 * </ul>
073 *
074 * @return the drivers
075 */
076 @Override
077 protected Map<String, FSMountFactory<?>> getMountFactories() {
078 return mountContexts;
079 }
080
081 /**
082 * Create the service loader discovery, this can be subclassed to provide an implementation, the current
083 * implementation returns a {@link ServiceLoaderDiscovery} instance.
084 *
085 * @param context the servlet context
086 * @param classLoader the class loader
087 * @return the plugin discovery
088 */
089 protected PluginDiscovery createDiscovery(ServletContext context, ClassLoader classLoader) {
090 return new ServiceLoaderDiscovery(classLoader);
091 }
092
093 public void contextInitialized(ServletContextEvent sce) {
094 context = sce.getServletContext();
095
096 // Use JVM properties as external config
097 setConfig(System.getProperties());
098
099 // Initialise the registerable drivers
100 try {
101 mountContexts.put("classpath", new ClassPathMountFactory(context.getClassLoader()));
102 mountContexts.put("file", new FileMountFactory(Utils.getCurrentDirectory()));
103 mountContexts.put("war", new WarMountFactory(context));
104 }
105 catch (Exception e) {
106 log.log(Level.SEVERE, "Coult not initialize classpath driver", e);
107 return;
108 }
109
110 //
111 String contextPath = context.getContextPath();
112 synchronized (lock) {
113 if (!contextMap.containsKey(contextPath)) {
114 ClassLoader webAppLoader = Thread.currentThread().getContextClassLoader();
115 PluginDiscovery discovery = createDiscovery(context, webAppLoader);
116 PluginContext pluginContext = start(new ServletContextMap(context), discovery, context.getClassLoader());
117 contextMap.put(contextPath, pluginContext);
118 registered = true;
119 }
120 }
121 }
122
123 /**
124 * The path property is resolved from the servlet context parameters. When the parameter does not exist,
125 * the <code>defaultValue</code> argument is used instead, so it should not be null.
126 * After the path is resolved, it is interpolated using the JVM system properties and the syntax
127 * defined by the {@link org.crsh.util.Utils#interpolate(String, java.util.Map)} function.
128 *
129 * @param propertyName the property name to resolve
130 * @param defaultValue the default property value
131 * @return the path value
132 */
133 private String resolvePathProperty(String propertyName, String defaultValue) {
134 String path = context.getInitParameter(propertyName);
135 if (path == null) {
136 path = defaultValue;
137 }
138 return Utils.interpolate(path, System.getProperties());
139 }
140
141 /**
142 * @return the value returned by {@link #resolvePathProperty(String, String)} with the <code>crash.mountpointconfig.conf</code> name
143 * and the {@link #getDefaultConfMountPointConfig()} default value
144 */
145 @Override
146 protected String resolveConfMountPointConfig() {
147 return resolvePathProperty("crash.mountpointconfig.conf", getDefaultConfMountPointConfig());
148 }
149
150 /**
151 * @return the value returned by {@link #resolvePathProperty(String, String)} with the <code>crash.mountpointconfig.cmd</code> name
152 * and the {@link #getDefaultCmdMountPointConfig()} default value
153 */
154 @Override
155 protected String resolveCmdMountPointConfig() {
156 return resolvePathProperty("crash.mountpointconfig.cmd", getDefaultCmdMountPointConfig());
157 }
158
159 /**
160 * @return <code>war:/WEB-INF/crash/commands/</code>
161 */
162 protected String getDefaultCmdMountPointConfig() {
163 return "war:/WEB-INF/crash/commands/";
164 }
165
166 /**
167 * @return <code>war:/WEB-INF/crash/</code>
168 */
169 protected String getDefaultConfMountPointConfig() {
170 return "war:/WEB-INF/crash";
171 }
172
173 public void contextDestroyed(ServletContextEvent sce) {
174 if (registered) {
175
176 //
177 ServletContext sc = sce.getServletContext();
178 String contextPath = sc.getContextPath();
179
180 //
181 synchronized (lock) {
182
183 //
184 contextMap.remove(contextPath);
185 registered = false;
186
187 //
188 stop();
189 }
190 }
191 }
192 }