001 /*
002 * Copyright (C) 2003-2009 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 package org.crsh.plugin;
020
021 import org.crsh.vfs.FS;
022 import org.crsh.vfs.File;
023 import org.crsh.vfs.Path;
024 import org.crsh.vfs.Resource;
025 import org.slf4j.Logger;
026 import org.slf4j.LoggerFactory;
027
028 import java.io.ByteArrayOutputStream;
029 import java.io.IOException;
030 import java.io.InputStream;
031 import java.util.*;
032 import java.util.concurrent.ExecutorService;
033 import java.util.concurrent.Executors;
034 import java.util.concurrent.ScheduledExecutorService;
035 import java.util.concurrent.ScheduledThreadPoolExecutor;
036 import java.util.concurrent.TimeUnit;
037 import java.util.regex.Matcher;
038 import java.util.regex.Pattern;
039
040 /**
041 * The plugin context.
042 *
043 * @author <a href="mailto:julien.viet@exoplatform.com">Julien Viet</a>
044 * @version $Revision$
045 */
046 public final class PluginContext {
047
048 /** . */
049 private static final Pattern p = Pattern.compile("(.+)\\.groovy");
050
051 /** . */
052 private static final Logger log = LoggerFactory.getLogger(PluginContext.class);
053
054 /** . */
055 final PluginManager manager;
056
057 /** . */
058 private final ClassLoader loader;
059
060 /** . */
061 private final String version;
062
063 /** . */
064 private ScheduledExecutorService scanner;
065
066 /** . */
067 private volatile List<File> dirs;
068
069 /** . */
070 private final Map<PropertyDescriptor<?>, Property<?>> properties;
071
072 /** . */
073 private final FS cmdFS;
074
075 /** . */
076 private final Map<String, ?> attributes;
077
078 /** . */
079 private final FS confFS;
080
081 /** . */
082 private boolean started;
083
084 /** The shared executor. */
085 private ExecutorService executor;
086
087
088 /**
089 * Create a new plugin context.
090 *
091 * @param discovery the plugin discovery
092 * @param cmdFS the command file system
093 * @param attributes the attributes
094 * @param confFS the conf file system
095 * @param loader the loader
096 * @throws NullPointerException if any parameter argument is null
097 */
098 public PluginContext(
099 PluginDiscovery discovery,
100 Map<String, ?> attributes,
101 FS cmdFS,
102 FS confFS,
103 ClassLoader loader) throws NullPointerException {
104 if (discovery == null) {
105 throw new NullPointerException("No null plugin disocovery accepted");
106 }
107 if (confFS == null) {
108 throw new NullPointerException("No null configuration file system accepted");
109 }
110 if (cmdFS == null) {
111 throw new NullPointerException("No null command file system accepted");
112 }
113 if (loader == null) {
114 throw new NullPointerException();
115 }
116 if (attributes == null) {
117 throw new NullPointerException();
118 }
119
120 //
121 String version = null;
122 try {
123 Properties props = new Properties();
124 InputStream in = getClass().getClassLoader().getResourceAsStream("META-INF/maven/org.crsh/crsh.shell.core/pom.properties");
125 if (in != null) {
126 props.load(in);
127 version = props.getProperty("version");
128 }
129 } catch (Exception e) {
130 log.error("Could not load maven properties", e);
131 }
132
133 //
134 if (version == null) {
135 log.warn("No version found will use unknown value instead");
136 version = "unknown";
137 }
138
139 //
140 this.loader = loader;
141 this.attributes = attributes;
142 this.version = version;
143 this.dirs = Collections.emptyList();
144 this.cmdFS = cmdFS;
145 this.properties = new HashMap<PropertyDescriptor<?>, Property<?>>();
146 this.started = false;
147 this.manager = new PluginManager(this, discovery);
148 this.confFS = confFS;
149 this.executor = Executors.newFixedThreadPool(20);
150 }
151
152 public Iterable<CRaSHPlugin<?>> getPlugins() {
153 return manager.getPlugins();
154 }
155
156 public String getVersion() {
157 return version;
158 }
159
160 public Map<String, ?> getAttributes() {
161 return attributes;
162 }
163
164 public ExecutorService getExecutor() {
165 return executor;
166 }
167
168 /**
169 * Returns a context property or null if it cannot be found.
170 *
171 * @param desc the property descriptor
172 * @param <T> the property parameter type
173 * @return the property value
174 * @throws NullPointerException if the descriptor argument is null
175 */
176 public <T> T getProperty(PropertyDescriptor<T> desc) throws NullPointerException {
177 if (desc == null) {
178 throw new NullPointerException();
179 }
180 Property<T> property = (Property<T>)properties.get(desc);
181 return property != null ? property.getValue() : desc.defaultValue;
182 }
183
184 /**
185 * Returns a context property or null if it cannot be found.
186 *
187 * @param propertyName the name of the property
188 * @param type the property type
189 * @param <T> the property parameter type
190 * @return the property value
191 * @throws NullPointerException if the descriptor argument is null
192 */
193 public <T> T getProperty(String propertyName, Class<T> type) throws NullPointerException {
194 if (propertyName == null) {
195 throw new NullPointerException("No null property name accepted");
196 }
197 if (type == null) {
198 throw new NullPointerException("No null property type accepted");
199 }
200 for (PropertyDescriptor<?> pd : properties.keySet())
201 {
202 if (pd.name.equals(propertyName) && type.isAssignableFrom(pd.type))
203 {
204 return type.cast(getProperty(pd));
205 }
206 }
207 return null;
208 }
209
210 /**
211 * Set a context property to a new value. If the provided value is null, then the property is removed.
212 *
213 * @param desc the property descriptor
214 * @param value the property value
215 * @param <T> the property parameter type
216 * @throws NullPointerException if the descriptor argument is null
217 */
218 public <T> void setProperty(PropertyDescriptor<T> desc, T value) throws NullPointerException {
219 if (desc == null) {
220 throw new NullPointerException();
221 }
222 if (value == null) {
223 log.debug("Removing property " + desc.name);
224 properties.remove(desc);
225 } else {
226 Property<T> property = new Property<T>(desc, value);
227 log.debug("Setting property " + desc.name + " to value " + property.getValue());
228 properties.put(desc, property);
229 }
230 }
231
232 /**
233 * Set a context property to a new value. If the provided value is null, then the property is removed.
234 *
235 * @param desc the property descriptor
236 * @param value the property value
237 * @param <T> the property parameter type
238 * @throws NullPointerException if the descriptor argument is null
239 * @throws IllegalArgumentException if the string value cannot be converted to the property type
240 */
241 public <T> void setProperty(PropertyDescriptor<T> desc, String value) throws NullPointerException, IllegalArgumentException {
242 if (desc == null) {
243 throw new NullPointerException();
244 }
245 if (value == null) {
246 log.debug("Removing property " + desc.name);
247 properties.remove(desc);
248 } else {
249 Property<T> property = desc.toProperty(value);
250 log.debug("Setting property " + desc.name + " to value " + property.getValue());
251 properties.put(desc, property);
252 }
253 }
254
255 /**
256 * Load a resource from the context.
257 *
258 * @param resourceId the resource id
259 * @param resourceKind the resource kind
260 * @return the resource or null if it cannot be found
261 */
262 public Resource loadResource(String resourceId, ResourceKind resourceKind) {
263 Resource res = null;
264 try {
265
266 //
267 switch (resourceKind) {
268 case LIFECYCLE:
269 if ("login".equals(resourceId) || "logout".equals(resourceId)) {
270 ByteArrayOutputStream buffer = new ByteArrayOutputStream();
271 long timestamp = Long.MIN_VALUE;
272 for (File path : dirs) {
273 File f = path.child(resourceId + ".groovy", false);
274 if (f != null) {
275 Resource sub = f.getResource();
276 if (sub != null) {
277 buffer.write(sub.getContent());
278 buffer.write('\n');
279 timestamp = Math.max(timestamp, sub.getTimestamp());
280 }
281 }
282 }
283 return new Resource(buffer.toByteArray(), timestamp);
284 }
285 break;
286 case COMMAND:
287 // Find the resource first, we find for the first found
288 for (File path : dirs) {
289 File f = path.child(resourceId + ".groovy", false);
290 if (f != null) {
291 res = f.getResource();
292 }
293 }
294 break;
295 case CONFIG:
296 String path = "/" + resourceId;
297 File file = confFS.get(Path.get(path));
298 if (file != null) {
299 res = file.getResource();
300 }
301 }
302 } catch (IOException e) {
303 log.warn("Could not obtain resource " + resourceId, e);
304 }
305 return res;
306 }
307
308 /**
309 * List the resources id for a specific resource kind.
310 *
311 * @param kind the resource kind
312 * @return the resource ids
313 */
314 public List<String> listResourceId(ResourceKind kind) {
315 switch (kind) {
316 case COMMAND:
317 SortedSet<String> all = new TreeSet<String>();
318 try {
319 for (File path : dirs) {
320 for (File file : path.children()) {
321 String name = file.getName();
322 Matcher matcher = p.matcher(name);
323 if (matcher.matches()) {
324 all.add(matcher.group(1));
325 }
326 }
327 }
328 }
329 catch (IOException e) {
330 e.printStackTrace();
331 }
332 all.remove("login");
333 all.remove("logout");
334 return new ArrayList<String>(all);
335 default:
336 return Collections.emptyList();
337 }
338 }
339
340 /**
341 * Returns the classloader associated with this context.
342 *
343 * @return the class loader
344 */
345 public ClassLoader getLoader() {
346 return loader;
347 }
348
349 /**
350 * Returns the plugins associated with this context.
351 *
352 * @param pluginType the plugin type
353 * @param <T> the plugin generic type
354 * @return the plugins
355 */
356 public <T> Iterable<T> getPlugins(Class<T> pluginType) {
357 return manager.getPlugins(pluginType);
358 }
359
360 /**
361 * Refresh the fs system view. This is normally triggered by the periodic job but it can be manually
362 * invoked to trigger explicit refreshes.
363 */
364 public void refresh() {
365 try {
366 File commands = cmdFS.get(Path.get("/"));
367 List<File> newDirs = new ArrayList<File>();
368 newDirs.add(commands);
369 for (File path : commands.children()) {
370 if (path.isDir()) {
371 newDirs.add(path);
372 }
373 }
374 dirs = newDirs;
375 }
376 catch (IOException e) {
377 e.printStackTrace();
378 }
379 }
380
381 synchronized void start() {
382 if (!started) {
383
384 // Start refresh
385 Integer refreshRate = getProperty(PropertyDescriptor.VFS_REFRESH_PERIOD);
386 TimeUnit timeUnit = getProperty(PropertyDescriptor.VFS_REFRESH_UNIT);
387 if (refreshRate != null && refreshRate > 0) {
388 TimeUnit tu = timeUnit != null ? timeUnit : TimeUnit.SECONDS;
389 scanner = new ScheduledThreadPoolExecutor(1);
390 scanner.scheduleWithFixedDelay(new Runnable() {
391 public void run() {
392 refresh();
393 }
394 }, 0, refreshRate, tu);
395 }
396
397 // Init plugins
398 manager.getPlugins(Object.class);
399
400 //
401 started = true;
402 } else {
403 log.warn("Attempt to double start");
404 }
405 }
406
407 synchronized void stop() {
408
409 //
410 if (started) {
411
412 // Shutdown manager
413 manager.shutdown();
414
415 // Shutdown scanner
416 if (scanner != null) {
417 ScheduledExecutorService tmp = scanner;
418 scanner = null;
419 tmp.shutdownNow();
420 }
421
422 // Shutdown executor
423 executor.shutdownNow();
424 } else {
425 log.warn("Attempt to stop when stopped");
426 }
427 }
428 }