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 */
019package org.crsh.plugin;
020
021import org.crsh.vfs.FS;
022import org.crsh.vfs.spi.FSMountFactory;
023
024import java.io.IOException;
025import java.util.Collections;
026import java.util.Map;
027import java.util.logging.Level;
028
029/**
030 * @author Julien Viet
031 */
032public class Embedded extends PluginLifeCycle {
033
034  /**
035   * Create the plugin context, allow subclasses to customize it.
036   *
037   * @param discovery the plugin discovery
038   * @return the plugin context
039   */
040  protected PluginContext create(Map<String, Object> attributes, PluginDiscovery discovery, ClassLoader loader) {
041
042    //
043    FS cmdFS;
044    FS confFS;
045    try {
046      cmdFS = createCommandFS();
047      confFS = createConfFS();
048    }
049    catch (IOException e) {
050      log.log(Level.SEVERE, "Coult not initialize the file system", e);
051      return null;
052    }
053
054    //
055    return new PluginContext(discovery, attributes, cmdFS, confFS, loader);
056  }
057
058  /**
059   * Create and start the plugin context.
060   *
061   * @param discovery the plugin discovery
062   * @return the plugin context
063   */
064  protected PluginContext start(Map<String, Object> attributes, PluginDiscovery discovery, ClassLoader loader) {
065    PluginContext context = create(attributes, discovery, loader);
066    if (context != null) {
067      context.refresh();
068      start(context);
069    }
070    return context;
071  }
072
073  /**
074   * Create the command file system from the <code>crash.mountpointconfig.cmd</code> servlet context parameter.
075   *
076   * @return the command file system
077   */
078  protected FS createCommandFS() throws IOException {
079    return createFS(resolveCmdMountPointConfig());
080  }
081
082  /**
083   * Create the conf file system from the <code>crash.mountpointconfig.conf</code> servlet context parameter.
084   *
085   * @return the conf file system
086   */
087  protected FS createConfFS() throws IOException {
088    return createFS(resolveConfMountPointConfig());
089  }
090
091  /**
092   * @return the registered drivers, by default an empty map is returned, subclasses can override to customize
093   */
094  protected Map<String, FSMountFactory<?>> getMountFactories() {
095    return Collections.emptyMap();
096  }
097
098  /**
099   * Create a new file system, configured by a the argument <code>mountPointConfig</code>: when the mount point
100   * configuration is not null, it is mounted on the returned file system.
101   *
102   * @param mountPointConfig the mount point configuration
103   * @return the configured file system
104   * @throws IOException any io exception
105   */
106  protected FS createFS(String mountPointConfig) throws IOException {
107    FS.Builder builder = new FS.Builder();
108    for (Map.Entry<String, FSMountFactory<?>> driver : getMountFactories().entrySet()) {
109      builder.register(driver.getKey(), driver.getValue());
110    }
111    if (mountPointConfig != null) {
112      builder.mount(mountPointConfig);
113    }
114    return builder.build();
115  }
116
117  protected String resolveConfMountPointConfig() {
118    return null;
119  }
120
121  protected String resolveCmdMountPointConfig() {
122    return null;
123  }
124}