001 /**
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements. See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership. The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License. You may obtain a copy of the License at
009 *
010 * http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018 package org.apache.oozie.action.hadoop;
019
020 import java.io.BufferedReader;
021 import java.io.ByteArrayOutputStream;
022 import java.io.File;
023 import java.io.FileNotFoundException;
024 import java.io.IOException;
025 import java.io.InputStream;
026 import java.io.InputStreamReader;
027 import java.io.PrintStream;
028 import java.io.StringReader;
029 import java.net.ConnectException;
030 import java.net.URI;
031 import java.net.URISyntaxException;
032 import java.net.UnknownHostException;
033 import java.util.ArrayList;
034 import java.util.HashMap;
035 import java.util.HashSet;
036 import java.util.Iterator;
037 import java.util.List;
038 import java.util.Map;
039 import java.util.Properties;
040 import java.util.Set;
041 import java.util.Map.Entry;
042
043 import org.apache.hadoop.conf.Configuration;
044 import org.apache.hadoop.filecache.DistributedCache;
045 import org.apache.hadoop.fs.FileStatus;
046 import org.apache.hadoop.fs.FileSystem;
047 import org.apache.hadoop.fs.Path;
048 import org.apache.hadoop.fs.permission.AccessControlException;
049 import org.apache.hadoop.mapred.JobClient;
050 import org.apache.hadoop.mapred.JobConf;
051 import org.apache.hadoop.mapred.JobID;
052 import org.apache.hadoop.mapred.RunningJob;
053 import org.apache.hadoop.mapreduce.security.token.delegation.DelegationTokenIdentifier;
054 import org.apache.hadoop.util.DiskChecker;
055 import org.apache.oozie.WorkflowActionBean;
056 import org.apache.oozie.WorkflowJobBean;
057 import org.apache.oozie.action.ActionExecutor;
058 import org.apache.oozie.action.ActionExecutorException;
059 import org.apache.oozie.client.OozieClient;
060 import org.apache.oozie.client.WorkflowAction;
061 import org.apache.oozie.service.HadoopAccessorException;
062 import org.apache.oozie.service.HadoopAccessorService;
063 import org.apache.oozie.service.Services;
064 import org.apache.oozie.service.WorkflowAppService;
065 import org.apache.oozie.servlet.CallbackServlet;
066 import org.apache.oozie.util.ELEvaluator;
067 import org.apache.oozie.util.IOUtils;
068 import org.apache.oozie.util.PropertiesUtils;
069 import org.apache.oozie.util.XConfiguration;
070 import org.apache.oozie.util.XLog;
071 import org.apache.oozie.util.XmlUtils;
072 import org.jdom.Element;
073 import org.jdom.JDOMException;
074 import org.jdom.Namespace;
075 import org.apache.hadoop.security.token.Token;
076 import org.apache.hadoop.security.token.TokenIdentifier;
077
078 public class JavaActionExecutor extends ActionExecutor {
079
080 private static final String HADOOP_USER = "user.name";
081 private static final String HADOOP_JOB_TRACKER = "mapred.job.tracker";
082 private static final String HADOOP_JOB_TRACKER_2 = "mapreduce.jobtracker.address";
083 private static final String HADOOP_YARN_RM = "yarn.resourcemanager.address";
084 private static final String HADOOP_NAME_NODE = "fs.default.name";
085 public static final String OOZIE_COMMON_LIBDIR = "oozie";
086 public static final int MAX_EXTERNAL_STATS_SIZE_DEFAULT = Integer.MAX_VALUE;
087 private static final Set<String> DISALLOWED_PROPERTIES = new HashSet<String>();
088 public final static String MAX_EXTERNAL_STATS_SIZE = "oozie.external.stats.max.size";
089 public static final String ACL_VIEW_JOB = "mapreduce.job.acl-view-job";
090 public static final String ACL_MODIFY_JOB = "mapreduce.job.acl-modify-job";
091 private static int maxActionOutputLen;
092 private static int maxExternalStatsSize;
093
094 private static final String SUCCEEDED = "SUCCEEDED";
095 private static final String KILLED = "KILLED";
096 private static final String FAILED = "FAILED";
097 private static final String FAILED_KILLED = "FAILED/KILLED";
098 private static final String RUNNING = "RUNNING";
099 protected XLog log = XLog.getLog(getClass());
100
101 static {
102 DISALLOWED_PROPERTIES.add(HADOOP_USER);
103 DISALLOWED_PROPERTIES.add(HADOOP_JOB_TRACKER);
104 DISALLOWED_PROPERTIES.add(HADOOP_NAME_NODE);
105 DISALLOWED_PROPERTIES.add(HADOOP_JOB_TRACKER_2);
106 DISALLOWED_PROPERTIES.add(HADOOP_YARN_RM);
107 }
108
109 public JavaActionExecutor() {
110 this("java");
111 requiresNNJT = true;
112 }
113
114 protected JavaActionExecutor(String type) {
115 super(type);
116 requiresNNJT = true;
117 }
118
119 protected String getLauncherJarName() {
120 return getType() + "-launcher.jar";
121 }
122
123 protected List<Class> getLauncherClasses() {
124 List<Class> classes = new ArrayList<Class>();
125 classes.add(LauncherMapper.class);
126 classes.add(LauncherSecurityManager.class);
127 classes.add(LauncherException.class);
128 classes.add(LauncherMainException.class);
129 classes.add(FileSystemActions.class);
130 classes.add(PrepareActionsDriver.class);
131 classes.add(ActionStats.class);
132 classes.add(ActionType.class);
133 return classes;
134 }
135
136 @Override
137 public void initActionType() {
138 XLog log = XLog.getLog(getClass());
139 super.initActionType();
140 maxActionOutputLen = getOozieConf()
141 .getInt(LauncherMapper.CONF_OOZIE_ACTION_MAX_OUTPUT_DATA,
142 // TODO: Remove the below config get in a subsequent release..
143 // This other irrelevant property is only used to
144 // preserve backwards compatibility cause of a typo.
145 // See OOZIE-4.
146 getOozieConf().getInt(CallbackServlet.CONF_MAX_DATA_LEN,
147 2 * 1024));
148 //Get the limit for the maximum allowed size of action stats
149 maxExternalStatsSize = getOozieConf().getInt(JavaActionExecutor.MAX_EXTERNAL_STATS_SIZE, MAX_EXTERNAL_STATS_SIZE_DEFAULT);
150 maxExternalStatsSize = (maxExternalStatsSize == -1) ? Integer.MAX_VALUE : maxExternalStatsSize;
151 try {
152 List<Class> classes = getLauncherClasses();
153 Class[] launcherClasses = classes.toArray(new Class[classes.size()]);
154 IOUtils.createJar(new File(getOozieRuntimeDir()), getLauncherJarName(), launcherClasses);
155
156 registerError(UnknownHostException.class.getName(), ActionExecutorException.ErrorType.TRANSIENT, "JA001");
157 registerError(AccessControlException.class.getName(), ActionExecutorException.ErrorType.NON_TRANSIENT,
158 "JA002");
159 registerError(DiskChecker.DiskOutOfSpaceException.class.getName(),
160 ActionExecutorException.ErrorType.NON_TRANSIENT, "JA003");
161 registerError(org.apache.hadoop.hdfs.protocol.QuotaExceededException.class.getName(),
162 ActionExecutorException.ErrorType.NON_TRANSIENT, "JA004");
163 registerError(org.apache.hadoop.hdfs.server.namenode.SafeModeException.class.getName(),
164 ActionExecutorException.ErrorType.NON_TRANSIENT, "JA005");
165 registerError(ConnectException.class.getName(), ActionExecutorException.ErrorType.TRANSIENT, " JA006");
166 registerError(JDOMException.class.getName(), ActionExecutorException.ErrorType.ERROR, "JA007");
167 registerError(FileNotFoundException.class.getName(), ActionExecutorException.ErrorType.ERROR, "JA008");
168 registerError(IOException.class.getName(), ActionExecutorException.ErrorType.TRANSIENT, "JA009");
169 }
170 catch (IOException ex) {
171 throw new RuntimeException(ex);
172 }
173 catch (java.lang.NoClassDefFoundError err) {
174 ByteArrayOutputStream baos = new ByteArrayOutputStream();
175 err.printStackTrace(new PrintStream(baos));
176 log.warn(baos.toString());
177 }
178 }
179
180 /**
181 * Get the maximum allowed size of stats
182 *
183 * @return maximum size of stats
184 */
185 public static int getMaxExternalStatsSize() {
186 return maxExternalStatsSize;
187 }
188
189 static void checkForDisallowedProps(Configuration conf, String confName) throws ActionExecutorException {
190 for (String prop : DISALLOWED_PROPERTIES) {
191 if (conf.get(prop) != null) {
192 throw new ActionExecutorException(ActionExecutorException.ErrorType.FAILED, "JA010",
193 "Property [{0}] not allowed in action [{1}] configuration", prop, confName);
194 }
195 }
196 }
197
198 public JobConf createBaseHadoopConf(Context context, Element actionXml) {
199 Namespace ns = actionXml.getNamespace();
200 String jobTracker = actionXml.getChild("job-tracker", ns).getTextTrim();
201 String nameNode = actionXml.getChild("name-node", ns).getTextTrim();
202 JobConf conf = Services.get().get(HadoopAccessorService.class).createJobConf(jobTracker);
203 conf.set(HADOOP_USER, context.getProtoActionConf().get(WorkflowAppService.HADOOP_USER));
204 conf.set(HADOOP_JOB_TRACKER, jobTracker);
205 conf.set(HADOOP_JOB_TRACKER_2, jobTracker);
206 conf.set(HADOOP_YARN_RM, jobTracker);
207 conf.set(HADOOP_NAME_NODE, nameNode);
208 conf.set("mapreduce.fileoutputcommitter.marksuccessfuljobs", "true");
209 return conf;
210 }
211
212 private void injectLauncherProperties(Configuration srcConf, Configuration launcherConf) {
213 for (Map.Entry<String, String> entry : srcConf) {
214 if (entry.getKey().startsWith("oozie.launcher.")) {
215 String name = entry.getKey().substring("oozie.launcher.".length());
216 String value = entry.getValue();
217 // setting original KEY
218 launcherConf.set(entry.getKey(), value);
219 // setting un-prefixed key (to allow Hadoop job config
220 // for the launcher job
221 launcherConf.set(name, value);
222 }
223 }
224 }
225
226 Configuration setupLauncherConf(Configuration conf, Element actionXml, Path appPath, Context context)
227 throws ActionExecutorException {
228 try {
229 Namespace ns = actionXml.getNamespace();
230 Element e = actionXml.getChild("configuration", ns);
231 if (e != null) {
232 String strConf = XmlUtils.prettyPrint(e).toString();
233 XConfiguration inlineConf = new XConfiguration(new StringReader(strConf));
234
235 XConfiguration launcherConf = new XConfiguration();
236 HadoopAccessorService has = Services.get().get(HadoopAccessorService.class);
237 XConfiguration actionDefaultConf = has.createActionDefaultConf(conf.get(HADOOP_JOB_TRACKER), getType());
238 injectLauncherProperties(actionDefaultConf, launcherConf);
239 injectLauncherProperties(inlineConf, launcherConf);
240 checkForDisallowedProps(launcherConf, "launcher configuration");
241 XConfiguration.copy(launcherConf, conf);
242 }
243 return conf;
244 }
245 catch (IOException ex) {
246 throw convertException(ex);
247 }
248 }
249
250 public static void parseJobXmlAndConfiguration(Context context, Element element, Path appPath, Configuration conf)
251 throws IOException, ActionExecutorException, HadoopAccessorException, URISyntaxException {
252 Namespace ns = element.getNamespace();
253 Iterator<Element> it = element.getChildren("job-xml", ns).iterator();
254 while (it.hasNext()) {
255 Element e = it.next();
256 String jobXml = e.getTextTrim();
257 Path path = new Path(appPath, jobXml);
258 FileSystem fs = context.getAppFileSystem();
259 Configuration jobXmlConf = new XConfiguration(fs.open(path));
260 checkForDisallowedProps(jobXmlConf, "job-xml");
261 XConfiguration.copy(jobXmlConf, conf);
262 }
263 Element e = element.getChild("configuration", ns);
264 if (e != null) {
265 String strConf = XmlUtils.prettyPrint(e).toString();
266 XConfiguration inlineConf = new XConfiguration(new StringReader(strConf));
267 checkForDisallowedProps(inlineConf, "inline configuration");
268 XConfiguration.copy(inlineConf, conf);
269 }
270 }
271
272 Configuration setupActionConf(Configuration actionConf, Context context, Element actionXml, Path appPath)
273 throws ActionExecutorException {
274 try {
275 HadoopAccessorService has = Services.get().get(HadoopAccessorService.class);
276 XConfiguration actionDefaults = has.createActionDefaultConf(actionConf.get(HADOOP_JOB_TRACKER), getType());
277 XConfiguration.injectDefaults(actionDefaults, actionConf);
278
279 has.checkSupportedFilesystem(appPath.toUri());
280
281 parseJobXmlAndConfiguration(context, actionXml, appPath, actionConf);
282 return actionConf;
283 }
284 catch (IOException ex) {
285 throw convertException(ex);
286 }
287 catch (HadoopAccessorException ex) {
288 throw convertException(ex);
289 }
290 catch (URISyntaxException ex) {
291 throw convertException(ex);
292 }
293 }
294
295 Configuration addToCache(Configuration conf, Path appPath, String filePath, boolean archive)
296 throws ActionExecutorException {
297 Path path = null;
298 try {
299 if (filePath.startsWith("/")) {
300 path = new Path(filePath);
301 }
302 else {
303 path = new Path(appPath, filePath);
304 }
305 URI uri = new URI(path.toUri().getPath());
306 if (archive) {
307 DistributedCache.addCacheArchive(uri, conf);
308 }
309 else {
310 String fileName = filePath.substring(filePath.lastIndexOf("/") + 1);
311 if (fileName.endsWith(".so") || fileName.contains(".so.")) { // .so files
312 uri = new Path(path.toString() + "#" + fileName).toUri();
313 uri = new URI(uri.getPath());
314 DistributedCache.addCacheFile(uri, conf);
315 }
316 else if (fileName.endsWith(".jar")) { // .jar files
317 if (!fileName.contains("#")) {
318 path = new Path(uri.toString());
319
320 String user = conf.get("user.name");
321 Services.get().get(HadoopAccessorService.class).addFileToClassPath(user, path, conf);
322 }
323 else {
324 DistributedCache.addCacheFile(uri, conf);
325 }
326 }
327 else { // regular files
328 if (!fileName.contains("#")) {
329 uri = new Path(path.toString() + "#" + fileName).toUri();
330 uri = new URI(uri.getPath());
331 }
332 DistributedCache.addCacheFile(uri, conf);
333 }
334 }
335 DistributedCache.createSymlink(conf);
336 return conf;
337 }
338 catch (Exception ex) {
339 XLog.getLog(getClass()).debug(
340 "Errors when add to DistributedCache. Path=" + path + ", archive=" + archive + ", conf="
341 + XmlUtils.prettyPrint(conf).toString());
342 throw convertException(ex);
343 }
344 }
345
346 String getOozieLauncherJar(Context context) throws ActionExecutorException {
347 try {
348 return new Path(context.getActionDir(), getLauncherJarName()).toString();
349 }
350 catch (Exception ex) {
351 throw convertException(ex);
352 }
353 }
354
355 public void prepareActionDir(FileSystem actionFs, Context context) throws ActionExecutorException {
356 try {
357 Path actionDir = context.getActionDir();
358 Path tempActionDir = new Path(actionDir.getParent(), actionDir.getName() + ".tmp");
359 if (!actionFs.exists(actionDir)) {
360 try {
361 actionFs.copyFromLocalFile(new Path(getOozieRuntimeDir(), getLauncherJarName()), new Path(
362 tempActionDir, getLauncherJarName()));
363 actionFs.rename(tempActionDir, actionDir);
364 }
365 catch (IOException ex) {
366 actionFs.delete(tempActionDir, true);
367 actionFs.delete(actionDir, true);
368 throw ex;
369 }
370 }
371 }
372 catch (Exception ex) {
373 throw convertException(ex);
374 }
375 }
376
377 void cleanUpActionDir(FileSystem actionFs, Context context) throws ActionExecutorException {
378 try {
379 Path actionDir = context.getActionDir();
380 if (!context.getProtoActionConf().getBoolean("oozie.action.keep.action.dir", false)
381 && actionFs.exists(actionDir)) {
382 actionFs.delete(actionDir, true);
383 }
384 }
385 catch (Exception ex) {
386 throw convertException(ex);
387 }
388 }
389
390 protected void addShareLib(Path appPath, Configuration conf, String actionShareLibName)
391 throws ActionExecutorException {
392 if (actionShareLibName != null) {
393 try {
394 Path systemLibPath = Services.get().get(WorkflowAppService.class).getSystemLibPath();
395 if (systemLibPath != null) {
396 Path actionLibPath = new Path(systemLibPath, actionShareLibName);
397 String user = conf.get("user.name");
398 FileSystem fs =
399 Services.get().get(HadoopAccessorService.class).createFileSystem(user, appPath.toUri(), conf);
400 if (fs.exists(actionLibPath)) {
401 FileStatus[] files = fs.listStatus(actionLibPath);
402 for (FileStatus file : files) {
403 addToCache(conf, appPath, file.getPath().toUri().getPath(), false);
404 }
405 }
406 }
407 }
408 catch (HadoopAccessorException ex){
409 throw new ActionExecutorException(ActionExecutorException.ErrorType.FAILED,
410 ex.getErrorCode().toString(), ex.getMessage());
411 }
412 catch (IOException ex){
413 throw new ActionExecutorException(ActionExecutorException.ErrorType.FAILED,
414 "It should never happen", ex.getMessage());
415 }
416 }
417 }
418
419 protected void addActionLibs(Path appPath, Configuration conf) throws ActionExecutorException {
420 String[] actionLibsStrArr = conf.getStrings("oozie.launcher.oozie.libpath");
421 if (actionLibsStrArr != null) {
422 try {
423 for (String actionLibsStr : actionLibsStrArr) {
424 actionLibsStr = actionLibsStr.trim();
425 if (actionLibsStr.length() > 0)
426 {
427 Path actionLibsPath = new Path(actionLibsStr);
428 String user = conf.get("user.name");
429 FileSystem fs = Services.get().get(HadoopAccessorService.class).createFileSystem(user, appPath.toUri(), conf);
430 if (fs.exists(actionLibsPath)) {
431 FileStatus[] files = fs.listStatus(actionLibsPath);
432 for (FileStatus file : files) {
433 addToCache(conf, appPath, file.getPath().toUri().getPath(), false);
434 }
435 }
436 }
437 }
438 }
439 catch (HadoopAccessorException ex){
440 throw new ActionExecutorException(ActionExecutorException.ErrorType.FAILED,
441 ex.getErrorCode().toString(), ex.getMessage());
442 }
443 catch (IOException ex){
444 throw new ActionExecutorException(ActionExecutorException.ErrorType.FAILED,
445 "It should never happen", ex.getMessage());
446 }
447 }
448 }
449
450 @SuppressWarnings("unchecked")
451 void setLibFilesArchives(Context context, Element actionXml, Path appPath, Configuration conf)
452 throws ActionExecutorException {
453 Configuration proto = context.getProtoActionConf();
454
455 // launcher JAR
456 addToCache(conf, appPath, getOozieLauncherJar(context), false);
457
458 // Workflow lib/
459 String[] paths = proto.getStrings(WorkflowAppService.APP_LIB_PATH_LIST);
460 if (paths != null) {
461 for (String path : paths) {
462 addToCache(conf, appPath, path, false);
463 }
464 }
465
466 // Action libs
467 addActionLibs(appPath, conf);
468
469 // files and archives defined in the action
470 for (Element eProp : (List<Element>) actionXml.getChildren()) {
471 if (eProp.getName().equals("file")) {
472 String path = eProp.getTextTrim();
473 addToCache(conf, appPath, path, false);
474 }
475 else {
476 if (eProp.getName().equals("archive")) {
477 String path = eProp.getTextTrim();
478 addToCache(conf, appPath, path, true);
479 }
480 }
481 }
482
483 addAllShareLibs(appPath, conf, context, actionXml);
484 }
485
486 // Adds action specific share libs and common share libs
487 private void addAllShareLibs(Path appPath, Configuration conf, Context context, Element actionXml)
488 throws ActionExecutorException {
489 // Add action specific share libs
490 addActionShareLib(appPath, conf, context, actionXml);
491 // Add common sharelibs for Oozie
492 addShareLib(appPath, conf, JavaActionExecutor.OOZIE_COMMON_LIBDIR);
493 }
494
495 private void addActionShareLib(Path appPath, Configuration conf, Context context, Element actionXml) throws ActionExecutorException {
496 XConfiguration wfJobConf = null;
497 try {
498 wfJobConf = new XConfiguration(new StringReader(context.getWorkflow().getConf()));
499 }
500 catch (IOException ioe) {
501 throw new ActionExecutorException(ActionExecutorException.ErrorType.FAILED, "It should never happen",
502 ioe.getMessage());
503 }
504 // Action sharelibs are only added if user has specified to use system libpath
505 if (wfJobConf.getBoolean(OozieClient.USE_SYSTEM_LIBPATH, false)) {
506 // add action specific sharelibs
507 addShareLib(appPath, conf, getShareLibName(context, actionXml, conf));
508 }
509 }
510
511
512 protected String getLauncherMain(Configuration launcherConf, Element actionXml) {
513 Namespace ns = actionXml.getNamespace();
514 Element e = actionXml.getChild("main-class", ns);
515 return e.getTextTrim();
516 }
517
518 private static final String QUEUE_NAME = "mapred.job.queue.name";
519
520 private static final Set<String> SPECIAL_PROPERTIES = new HashSet<String>();
521
522 static {
523 SPECIAL_PROPERTIES.add(QUEUE_NAME);
524 SPECIAL_PROPERTIES.add(ACL_VIEW_JOB);
525 SPECIAL_PROPERTIES.add(ACL_MODIFY_JOB);
526 }
527
528 @SuppressWarnings("unchecked")
529 JobConf createLauncherConf(FileSystem actionFs, Context context, WorkflowAction action, Element actionXml, Configuration actionConf)
530 throws ActionExecutorException {
531 try {
532
533 // app path could be a file
534 Path appPathRoot = new Path(context.getWorkflow().getAppPath());
535 if (actionFs.isFile(appPathRoot)) {
536 appPathRoot = appPathRoot.getParent();
537 }
538
539 // launcher job configuration
540 JobConf launcherJobConf = createBaseHadoopConf(context, actionXml);
541 setupLauncherConf(launcherJobConf, actionXml, appPathRoot, context);
542
543 String actionShareLibProperty = actionConf.get(ACTION_SHARELIB_FOR + getType());
544 if (actionShareLibProperty != null) {
545 launcherJobConf.set(ACTION_SHARELIB_FOR + getType(), actionShareLibProperty);
546 }
547 setLibFilesArchives(context, actionXml, appPathRoot, launcherJobConf);
548 String jobName = XLog.format("oozie:launcher:T={0}:W={1}:A={2}:ID={3}", getType(), context.getWorkflow()
549 .getAppName(), action.getName(), context.getWorkflow().getId());
550 launcherJobConf.setJobName(jobName);
551
552 String jobId = context.getWorkflow().getId();
553 String actionId = action.getId();
554 Path actionDir = context.getActionDir();
555 String recoveryId = context.getRecoveryId();
556
557 // Getting the prepare XML from the action XML
558 Namespace ns = actionXml.getNamespace();
559 Element prepareElement = actionXml.getChild("prepare", ns);
560 String prepareXML = "";
561 if (prepareElement != null) {
562 if (prepareElement.getChildren().size() > 0) {
563 prepareXML = XmlUtils.prettyPrint(prepareElement).toString().trim();
564 }
565 }
566 LauncherMapper.setupLauncherInfo(launcherJobConf, jobId, actionId, actionDir, recoveryId, actionConf,
567 prepareXML);
568
569 LauncherMapper.setupMainClass(launcherJobConf, getLauncherMain(launcherJobConf, actionXml));
570 LauncherMapper.setupSupportedFileSystems(
571 launcherJobConf, Services.get().getConf().get(HadoopAccessorService.SUPPORTED_FILESYSTEMS));
572 LauncherMapper.setupMaxOutputData(launcherJobConf, maxActionOutputLen);
573 LauncherMapper.setupMaxExternalStatsSize(launcherJobConf, maxExternalStatsSize);
574
575 List<Element> list = actionXml.getChildren("arg", ns);
576 String[] args = new String[list.size()];
577 for (int i = 0; i < list.size(); i++) {
578 args[i] = list.get(i).getTextTrim();
579 }
580 LauncherMapper.setupMainArguments(launcherJobConf, args);
581
582 List<Element> javaopts = actionXml.getChildren("java-opt", ns);
583 for (Element opt: javaopts) {
584 String opts = launcherJobConf.get("mapred.child.java.opts", "");
585 opts = opts + " " + opt.getTextTrim();
586 opts = opts.trim();
587 launcherJobConf.set("mapred.child.java.opts", opts);
588 }
589
590 Element opt = actionXml.getChild("java-opts", ns);
591 if (opt != null) {
592 String opts = launcherJobConf.get("mapred.child.java.opts", "");
593 opts = opts + " " + opt.getTextTrim();
594 opts = opts.trim();
595 launcherJobConf.set("mapred.child.java.opts", opts);
596 }
597
598 // properties from action that are needed by the launcher (e.g. QUEUE NAME, ACLs)
599 // maybe we should add queue to the WF schema, below job-tracker
600 actionConfToLauncherConf(actionConf, launcherJobConf);
601
602 // to disable cancelation of delegation token on launcher job end
603 launcherJobConf.setBoolean("mapreduce.job.complete.cancel.delegation.tokens", false);
604
605 return launcherJobConf;
606 }
607 catch (Exception ex) {
608 throw convertException(ex);
609 }
610 }
611
612 private void injectCallback(Context context, Configuration conf) {
613 String callback = context.getCallbackUrl("$jobStatus");
614 if (conf.get("job.end.notification.url") != null) {
615 XLog.getLog(getClass()).warn("Overriding the action job end notification URI");
616 }
617 conf.set("job.end.notification.url", callback);
618 }
619
620 void injectActionCallback(Context context, Configuration actionConf) {
621 injectCallback(context, actionConf);
622 }
623
624 void injectLauncherCallback(Context context, Configuration launcherConf) {
625 injectCallback(context, launcherConf);
626 }
627
628 private void actionConfToLauncherConf(Configuration actionConf, JobConf launcherConf) {
629 for (String name : SPECIAL_PROPERTIES) {
630 if (actionConf.get(name) != null && launcherConf.get("oozie.launcher." + name) == null) {
631 launcherConf.set(name, actionConf.get(name));
632 }
633 }
634 }
635
636 public void submitLauncher(FileSystem actionFs, Context context, WorkflowAction action) throws ActionExecutorException {
637 JobClient jobClient = null;
638 boolean exception = false;
639 try {
640 Path appPathRoot = new Path(context.getWorkflow().getAppPath());
641
642 // app path could be a file
643 if (actionFs.isFile(appPathRoot)) {
644 appPathRoot = appPathRoot.getParent();
645 }
646
647 Element actionXml = XmlUtils.parseXml(action.getConf());
648
649 // action job configuration
650 Configuration actionConf = createBaseHadoopConf(context, actionXml);
651 setupActionConf(actionConf, context, actionXml, appPathRoot);
652 XLog.getLog(getClass()).debug("Setting LibFilesArchives ");
653 setLibFilesArchives(context, actionXml, appPathRoot, actionConf);
654 String jobName = XLog.format("oozie:action:T={0}:W={1}:A={2}:ID={3}", getType(), context.getWorkflow()
655 .getAppName(), action.getName(), context.getWorkflow().getId());
656 actionConf.set("mapred.job.name", jobName);
657 injectActionCallback(context, actionConf);
658
659 if(actionConf.get(ACL_MODIFY_JOB) == null || actionConf.get(ACL_MODIFY_JOB).trim().equals("")) {
660 // ONLY in the case where user has not given the
661 // modify-job ACL specifically
662 if (context.getWorkflow().getAcl() != null) {
663 // setting the group owning the Oozie job to allow anybody in that
664 // group to modify the jobs.
665 actionConf.set(ACL_MODIFY_JOB, context.getWorkflow().getAcl());
666 }
667 }
668
669 // Setting the credential properties in launcher conf
670 HashMap<String, CredentialsProperties> credentialsProperties = setCredentialPropertyToActionConf(context,
671 action, actionConf);
672
673 // Adding if action need to set more credential tokens
674 JobConf credentialsConf = new JobConf(false);
675 XConfiguration.copy(actionConf, credentialsConf);
676 setCredentialTokens(credentialsConf, context, action, credentialsProperties);
677
678 // insert conf to action conf from credentialsConf
679 for (Entry<String, String> entry : credentialsConf) {
680 if (actionConf.get(entry.getKey()) == null) {
681 actionConf.set(entry.getKey(), entry.getValue());
682 }
683 }
684
685 JobConf launcherJobConf = createLauncherConf(actionFs, context, action, actionXml, actionConf);
686 injectLauncherCallback(context, launcherJobConf);
687 XLog.getLog(getClass()).debug("Creating Job Client for action " + action.getId());
688 jobClient = createJobClient(context, launcherJobConf);
689 String launcherId = LauncherMapper.getRecoveryId(launcherJobConf, context.getActionDir(), context
690 .getRecoveryId());
691 boolean alreadyRunning = launcherId != null;
692 RunningJob runningJob;
693
694 // if user-retry is on, always submit new launcher
695 boolean isUserRetry = ((WorkflowActionBean)action).isUserRetry();
696
697 if (alreadyRunning && !isUserRetry) {
698 runningJob = jobClient.getJob(JobID.forName(launcherId));
699 if (runningJob == null) {
700 String jobTracker = launcherJobConf.get("mapred.job.tracker");
701 throw new ActionExecutorException(ActionExecutorException.ErrorType.ERROR, "JA017",
702 "unknown job [{0}@{1}], cannot recover", launcherId, jobTracker);
703 }
704 }
705 else {
706 XLog.getLog(getClass()).debug("Submitting the job through Job Client for action " + action.getId());
707
708 // setting up propagation of the delegation token.
709 Token<DelegationTokenIdentifier> mrdt = jobClient.getDelegationToken(HadoopAccessorService
710 .getMRDelegationTokenRenewer(launcherJobConf));
711 launcherJobConf.getCredentials().addToken(HadoopAccessorService.MR_TOKEN_ALIAS, mrdt);
712
713 // insert credentials tokens to launcher job conf if needed
714 if (needInjectCredentials()) {
715 for (Token<? extends TokenIdentifier> tk : credentialsConf.getCredentials().getAllTokens()) {
716 log.debug("ADDING TOKEN: " + tk.getKind().toString());
717 launcherJobConf.getCredentials().addToken(tk.getKind(), tk);
718 }
719 }
720 else {
721 log.info("No need to inject credentials.");
722 }
723 runningJob = jobClient.submitJob(launcherJobConf);
724 if (runningJob == null) {
725 throw new ActionExecutorException(ActionExecutorException.ErrorType.ERROR, "JA017",
726 "Error submitting launcher for action [{0}]", action.getId());
727 }
728 launcherId = runningJob.getID().toString();
729 XLog.getLog(getClass()).debug("After submission get the launcherId " + launcherId);
730 }
731
732 String jobTracker = launcherJobConf.get(HADOOP_JOB_TRACKER);
733 String consoleUrl = runningJob.getTrackingURL();
734 context.setStartData(launcherId, jobTracker, consoleUrl);
735 }
736 catch (Exception ex) {
737 exception = true;
738 throw convertException(ex);
739 }
740 finally {
741 if (jobClient != null) {
742 try {
743 jobClient.close();
744 }
745 catch (Exception e) {
746 if (exception) {
747 log.error("JobClient error: ", e);
748 }
749 else {
750 throw convertException(e);
751 }
752 }
753 }
754 }
755 }
756
757 private boolean needInjectCredentials() {
758 boolean methodExists = true;
759
760 Class klass;
761 try {
762 klass = Class.forName("org.apache.hadoop.mapred.JobConf");
763 klass.getMethod("getCredentials");
764 }
765 catch (ClassNotFoundException ex) {
766 methodExists = false;
767 }
768 catch (NoSuchMethodException ex) {
769 methodExists = false;
770 }
771
772 return methodExists;
773 }
774
775 protected HashMap<String, CredentialsProperties> setCredentialPropertyToActionConf(Context context,
776 WorkflowAction action, Configuration actionConf) throws Exception {
777 HashMap<String, CredentialsProperties> credPropertiesMap = null;
778 if (context != null && action != null) {
779 credPropertiesMap = getActionCredentialsProperties(context, action);
780 if (credPropertiesMap != null) {
781 for (String key : credPropertiesMap.keySet()) {
782 CredentialsProperties prop = credPropertiesMap.get(key);
783 if (prop != null) {
784 log.debug("Credential Properties set for action : " + action.getId());
785 for (String property : prop.getProperties().keySet()) {
786 actionConf.set(property, prop.getProperties().get(property));
787 log.debug("property : '" + property + "', value : '" + prop.getProperties().get(property) + "'");
788 }
789 }
790 }
791 }
792 else {
793 log.warn("No credential properties found for action : " + action.getId() + ", cred : " + action.getCred());
794 }
795 }
796 else {
797 log.warn("context or action is null");
798 }
799 return credPropertiesMap;
800 }
801
802 protected void setCredentialTokens(JobConf jobconf, Context context, WorkflowAction action,
803 HashMap<String, CredentialsProperties> credPropertiesMap) throws Exception {
804
805 if (context != null && action != null && credPropertiesMap != null) {
806 for (Entry<String, CredentialsProperties> entry : credPropertiesMap.entrySet()) {
807 String credName = entry.getKey();
808 CredentialsProperties credProps = entry.getValue();
809 if (credProps != null) {
810 CredentialsProvider credProvider = new CredentialsProvider(credProps.getType());
811 Credentials credentialObject = credProvider.createCredentialObject();
812 if (credentialObject != null) {
813 credentialObject.addtoJobConf(jobconf, credProps, context);
814 log.debug("Retrieved Credential '" + credName + "' for action " + action.getId());
815 }
816 else {
817 log.debug("Credentials object is null for name= " + credName + ", type=" + credProps.getType());
818 }
819 }
820 }
821 }
822
823 }
824
825 protected HashMap<String, CredentialsProperties> getActionCredentialsProperties(Context context,
826 WorkflowAction action) throws Exception {
827 HashMap<String, CredentialsProperties> props = new HashMap<String, CredentialsProperties>();
828 if (context != null && action != null) {
829 String credsInAction = action.getCred();
830 log.debug("Get credential '" + credsInAction + "' properties for action : " + action.getId());
831 String[] credNames = credsInAction.split(",");
832 for (String credName : credNames) {
833 CredentialsProperties credProps = getCredProperties(context, credName);
834 props.put(credName, credProps);
835 }
836 }
837 else {
838 log.warn("context or action is null");
839 }
840 return props;
841 }
842
843 @SuppressWarnings("unchecked")
844 protected CredentialsProperties getCredProperties(Context context, String credName)
845 throws Exception {
846 CredentialsProperties credProp = null;
847 String workflowXml = ((WorkflowJobBean) context.getWorkflow()).getWorkflowInstance().getApp().getDefinition();
848 XConfiguration wfjobConf = new XConfiguration(new StringReader(context.getWorkflow().getConf()));
849 Element elementJob = XmlUtils.parseXml(workflowXml);
850 Element credentials = elementJob.getChild("credentials", elementJob.getNamespace());
851 if (credentials != null) {
852 for (Element credential : (List<Element>) credentials.getChildren("credential", credentials.getNamespace())) {
853 String name = credential.getAttributeValue("name");
854 String type = credential.getAttributeValue("type");
855 log.debug("getCredProperties: Name: " + name + ", Type: " + type);
856 if (name.equalsIgnoreCase(credName)) {
857 credProp = new CredentialsProperties(name, type);
858 for (Element property : (List<Element>) credential.getChildren("property",
859 credential.getNamespace())) {
860 String propertyName = property.getChildText("name", property.getNamespace());
861 String propertyValue = property.getChildText("value", property.getNamespace());
862 ELEvaluator eval = new ELEvaluator();
863 for (Map.Entry<String, String> entry : wfjobConf) {
864 eval.setVariable(entry.getKey(), entry.getValue().trim());
865 }
866 propertyName = eval.evaluate(propertyName, String.class);
867 propertyValue = eval.evaluate(propertyValue, String.class);
868
869 credProp.getProperties().put(propertyName, propertyValue);
870 log.debug("getCredProperties: Properties name :'" + propertyName + "', Value : '"
871 + propertyValue + "'");
872 }
873 }
874 }
875 } else {
876 log.warn("credentials is null for the action");
877 }
878 return credProp;
879 }
880
881 @Override
882 public void start(Context context, WorkflowAction action) throws ActionExecutorException {
883 try {
884 XLog.getLog(getClass()).debug("Starting action " + action.getId() + " getting Action File System");
885 FileSystem actionFs = context.getAppFileSystem();
886 XLog.getLog(getClass()).debug("Preparing action Dir through copying " + context.getActionDir());
887 prepareActionDir(actionFs, context);
888 XLog.getLog(getClass()).debug("Action Dir is ready. Submitting the action ");
889 submitLauncher(actionFs, context, action);
890 XLog.getLog(getClass()).debug("Action submit completed. Performing check ");
891 check(context, action);
892 XLog.getLog(getClass()).debug("Action check is done after submission");
893 }
894 catch (Exception ex) {
895 throw convertException(ex);
896 }
897 }
898
899 @Override
900 public void end(Context context, WorkflowAction action) throws ActionExecutorException {
901 try {
902 String externalStatus = action.getExternalStatus();
903 WorkflowAction.Status status = externalStatus.equals(SUCCEEDED) ? WorkflowAction.Status.OK
904 : WorkflowAction.Status.ERROR;
905 context.setEndData(status, getActionSignal(status));
906 }
907 catch (Exception ex) {
908 throw convertException(ex);
909 }
910 finally {
911 try {
912 FileSystem actionFs = context.getAppFileSystem();
913 cleanUpActionDir(actionFs, context);
914 }
915 catch (Exception ex) {
916 throw convertException(ex);
917 }
918 }
919 }
920
921 /**
922 * Create job client object
923 *
924 * @param context
925 * @param jobConf
926 * @return
927 * @throws HadoopAccessorException
928 */
929 protected JobClient createJobClient(Context context, JobConf jobConf) throws HadoopAccessorException {
930 String user = context.getWorkflow().getUser();
931 String group = context.getWorkflow().getGroup();
932 return Services.get().get(HadoopAccessorService.class).createJobClient(user, jobConf);
933 }
934
935 @Override
936 public void check(Context context, WorkflowAction action) throws ActionExecutorException {
937 JobClient jobClient = null;
938 boolean exception = false;
939 try {
940 Element actionXml = XmlUtils.parseXml(action.getConf());
941 FileSystem actionFs = context.getAppFileSystem();
942 JobConf jobConf = createBaseHadoopConf(context, actionXml);
943 jobClient = createJobClient(context, jobConf);
944 RunningJob runningJob = jobClient.getJob(JobID.forName(action.getExternalId()));
945 if (runningJob == null) {
946 context.setExternalStatus(FAILED);
947 context.setExecutionData(FAILED, null);
948 throw new ActionExecutorException(ActionExecutorException.ErrorType.FAILED, "JA017",
949 "Unknown hadoop job [{0}] associated with action [{1}]. Failing this action!", action
950 .getExternalId(), action.getId());
951 }
952 if (runningJob.isComplete()) {
953 Path actionDir = context.getActionDir();
954
955 String user = context.getWorkflow().getUser();
956 String group = context.getWorkflow().getGroup();
957 if (LauncherMapper.hasIdSwap(runningJob, user, group, actionDir)) {
958 String launcherId = action.getExternalId();
959 Path idSwapPath = LauncherMapper.getIdSwapPath(context.getActionDir());
960 InputStream is = actionFs.open(idSwapPath);
961 BufferedReader reader = new BufferedReader(new InputStreamReader(is));
962 Properties props = PropertiesUtils.readProperties(reader, maxActionOutputLen);
963 reader.close();
964 String newId = props.getProperty("id");
965 runningJob = jobClient.getJob(JobID.forName(newId));
966 if (runningJob == null) {
967 context.setExternalStatus(FAILED);
968 throw new ActionExecutorException(ActionExecutorException.ErrorType.FAILED, "JA017",
969 "Unknown hadoop job [{0}] associated with action [{1}]. Failing this action!", newId,
970 action.getId());
971 }
972
973 context.setStartData(newId, action.getTrackerUri(), runningJob.getTrackingURL());
974 XLog.getLog(getClass()).info(XLog.STD, "External ID swap, old ID [{0}] new ID [{1}]", launcherId,
975 newId);
976 }
977 if (runningJob.isComplete()) {
978 XLog.getLog(getClass()).info(XLog.STD, "action completed, external ID [{0}]",
979 action.getExternalId());
980 if (runningJob.isSuccessful() && LauncherMapper.isMainSuccessful(runningJob)) {
981 getActionData(actionFs, runningJob, action, context);
982 XLog.getLog(getClass()).info(XLog.STD, "action produced output");
983 }
984 else {
985 XLog log = XLog.getLog(getClass());
986 String errorReason;
987 Path actionError = LauncherMapper.getErrorPath(context.getActionDir());
988 if (actionFs.exists(actionError)) {
989 InputStream is = actionFs.open(actionError);
990 BufferedReader reader = new BufferedReader(new InputStreamReader(is));
991 Properties props = PropertiesUtils.readProperties(reader, -1);
992 reader.close();
993 String errorCode = props.getProperty("error.code");
994 if (errorCode.equals("0")) {
995 errorCode = "JA018";
996 }
997 if (errorCode.equals("-1")) {
998 errorCode = "JA019";
999 }
1000 errorReason = props.getProperty("error.reason");
1001 log.warn("Launcher ERROR, reason: {0}", errorReason);
1002 String exMsg = props.getProperty("exception.message");
1003 String errorInfo = (exMsg != null) ? exMsg : errorReason;
1004 context.setErrorInfo(errorCode, errorInfo);
1005 String exStackTrace = props.getProperty("exception.stacktrace");
1006 if (exMsg != null) {
1007 log.warn("Launcher exception: {0}{E}{1}", exMsg, exStackTrace);
1008 }
1009 }
1010 else {
1011 errorReason = XLog.format("LauncherMapper died, check Hadoop log for job [{0}:{1}]", action
1012 .getTrackerUri(), action.getExternalId());
1013 log.warn(errorReason);
1014 }
1015 context.setExecutionData(FAILED_KILLED, null);
1016 }
1017 }
1018 else {
1019 context.setExternalStatus(RUNNING);
1020 XLog.getLog(getClass()).info(XLog.STD, "checking action, external ID [{0}] status [{1}]",
1021 action.getExternalId(), action.getExternalStatus());
1022 }
1023 }
1024 else {
1025 context.setExternalStatus(RUNNING);
1026 XLog.getLog(getClass()).info(XLog.STD, "checking action, external ID [{0}] status [{1}]",
1027 action.getExternalId(), action.getExternalStatus());
1028 }
1029 }
1030 catch (Exception ex) {
1031 XLog.getLog(getClass()).warn("Exception in check(). Message[{0}]", ex.getMessage(), ex);
1032 exception = true;
1033 throw convertException(ex);
1034 }
1035 finally {
1036 if (jobClient != null) {
1037 try {
1038 jobClient.close();
1039 }
1040 catch (Exception e) {
1041 if (exception) {
1042 log.error("JobClient error: ", e);
1043 }
1044 else {
1045 throw convertException(e);
1046 }
1047 }
1048 }
1049 }
1050 }
1051
1052 /**
1053 * Get the output data of an action. Subclasses should override this method
1054 * to get action specific output data.
1055 *
1056 * @param actionFs the FileSystem object
1057 * @param runningJob the runningJob
1058 * @param action the Workflow action
1059 * @param context executor context
1060 *
1061 */
1062 protected void getActionData(FileSystem actionFs, RunningJob runningJob, WorkflowAction action, Context context)
1063 throws HadoopAccessorException, JDOMException, IOException, URISyntaxException {
1064 Properties props = null;
1065 if (getCaptureOutput(action)) {
1066 props = new Properties();
1067 if (LauncherMapper.hasOutputData(runningJob)) {
1068 Path actionOutput = LauncherMapper.getOutputDataPath(context.getActionDir());
1069 InputStream is = actionFs.open(actionOutput);
1070 BufferedReader reader = new BufferedReader(new InputStreamReader(is));
1071 props = PropertiesUtils.readProperties(reader, maxActionOutputLen);
1072 reader.close();
1073 }
1074 }
1075 context.setExecutionData(SUCCEEDED, props);
1076 }
1077
1078 protected boolean getCaptureOutput(WorkflowAction action) throws JDOMException {
1079 Element eConf = XmlUtils.parseXml(action.getConf());
1080 Namespace ns = eConf.getNamespace();
1081 Element captureOutput = eConf.getChild("capture-output", ns);
1082 return captureOutput != null;
1083 }
1084
1085 @Override
1086 public void kill(Context context, WorkflowAction action) throws ActionExecutorException {
1087 JobClient jobClient = null;
1088 boolean exception = false;
1089 try {
1090 Element actionXml = XmlUtils.parseXml(action.getConf());
1091 JobConf jobConf = createBaseHadoopConf(context, actionXml);
1092 jobClient = createJobClient(context, jobConf);
1093 RunningJob runningJob = jobClient.getJob(JobID.forName(action.getExternalId()));
1094 if (runningJob != null) {
1095 runningJob.killJob();
1096 }
1097 context.setExternalStatus(KILLED);
1098 context.setExecutionData(KILLED, null);
1099 }
1100 catch (Exception ex) {
1101 exception = true;
1102 throw convertException(ex);
1103 }
1104 finally {
1105 try {
1106 FileSystem actionFs = context.getAppFileSystem();
1107 cleanUpActionDir(actionFs, context);
1108 if (jobClient != null) {
1109 jobClient.close();
1110 }
1111 }
1112 catch (Exception ex) {
1113 if (exception) {
1114 log.error("Error: ", ex);
1115 }
1116 else {
1117 throw convertException(ex);
1118 }
1119 }
1120 }
1121 }
1122
1123 private static Set<String> FINAL_STATUS = new HashSet<String>();
1124
1125 static {
1126 FINAL_STATUS.add(SUCCEEDED);
1127 FINAL_STATUS.add(KILLED);
1128 FINAL_STATUS.add(FAILED);
1129 FINAL_STATUS.add(FAILED_KILLED);
1130 }
1131
1132 @Override
1133 public boolean isCompleted(String externalStatus) {
1134 return FINAL_STATUS.contains(externalStatus);
1135 }
1136
1137
1138 /**
1139 * Return the sharelib name for the action.
1140 * <p/>
1141 * If <code>NULL</code> or emtpy, it means that the action does not use the action
1142 * sharelib.
1143 * <p/>
1144 * If a non-empty string, i.e. <code>foo</code>, it means the action uses the
1145 * action sharelib subdirectory <code>foo</code> and all JARs in the sharelib
1146 * <code>foo</code> directory will be in the action classpath.
1147 * <p/>
1148 * The resolution is done using the following precedence order:
1149 * <ul>
1150 * <li><b>action.sharelib.for.#ACTIONTYPE#</b> in the action configuration</li>
1151 * <li><b>action.sharelib.for.#ACTIONTYPE#</b> in the job configuration</li>
1152 * <li><b>action.sharelib.for.#ACTIONTYPE#</b> in the oozie configuration</li>
1153 * <li>Action Executor <code>getDefaultShareLibName()</code> method</li>
1154 * </ul>
1155 *
1156 *
1157 * @param context executor context.
1158 * @param actionXml
1159 *@param conf action configuration. @return the action sharelib name.
1160 */
1161 protected String getShareLibName(Context context, Element actionXml, Configuration conf) {
1162 String name = conf.get(ACTION_SHARELIB_FOR + getType());
1163 if (name == null) {
1164 try {
1165 XConfiguration jobConf = new XConfiguration(new StringReader(context.getWorkflow().getConf()));
1166 name = jobConf.get(ACTION_SHARELIB_FOR + getType());
1167 if (name == null) {
1168 name = Services.get().getConf().get(ACTION_SHARELIB_FOR + getType());
1169 if (name == null) {
1170 name = getDefaultShareLibName(actionXml);
1171 }
1172 }
1173 }
1174 catch (IOException ex) {
1175 throw new RuntimeException("It cannot happen, " + ex.toString(), ex);
1176 }
1177 }
1178 return name;
1179 }
1180
1181 private final static String ACTION_SHARELIB_FOR = "oozie.action.sharelib.for.";
1182
1183
1184 /**
1185 * Returns the default sharelib name for the action if any.
1186 *
1187 * @param actionXml the action XML fragment.
1188 * @return the sharelib name for the action, <code>NULL</code> if none.
1189 */
1190 protected String getDefaultShareLibName(Element actionXml) {
1191 return null;
1192 }
1193 }