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
019package org.apache.oozie.dependency;
020
021import java.net.URI;
022import java.net.URISyntaxException;
023import java.util.ArrayList;
024import java.util.Arrays;
025import java.util.List;
026
027import org.apache.commons.lang.StringUtils;
028import org.apache.hadoop.conf.Configuration;
029import org.apache.oozie.ErrorCode;
030import org.apache.oozie.client.OozieClient;
031import org.apache.oozie.command.CommandException;
032import org.apache.oozie.coord.CoordELFunctions;
033import org.apache.oozie.service.Services;
034import org.apache.oozie.service.URIHandlerService;
035import org.apache.oozie.util.ParamChecker;
036import org.apache.oozie.util.XLog;
037
038public class DependencyChecker {
039
040    /**
041     * Return a string of missing dependencies concatenated by CoordELFunctions.INSTANCE_SEPARATOR
042     *
043     * @param missingDependencies list of missing dependencies
044     * @return missing dependencies as a string
045     */
046    public static String dependenciesAsString(List<String> missingDependencies) {
047        return StringUtils.join(missingDependencies, CoordELFunctions.INSTANCE_SEPARATOR);
048    }
049
050    /**
051     * Return a array of missing dependencies
052     *
053     * @param missingDependencies missing dependencies concatenated by
054     *        CoordELFunctions.INSTANCE_SEPARATOR
055     * @return missing dependencies as a array
056     */
057    public static String[] dependenciesAsArray(String missingDependencies) {
058        if(StringUtils.isEmpty(missingDependencies)){
059            return new String[0];
060        }
061        return missingDependencies.split(CoordELFunctions.INSTANCE_SEPARATOR);
062    }
063
064    /**
065     * Get the currently missing and available dependencies after checking the list of known missing
066     * dependencies against the source.
067     *
068     * @param missingDependencies known missing dependencies
069     * @param actionConf Configuration for the action
070     * @param stopOnFirstMissing Does not continue check for the rest of list if there is a missing
071     *        dependency
072     * @return ActionDependency which has the list of missing and available dependencies
073     * @throws CommandException in case of error
074     */
075    public static ActionDependency checkForAvailability(String missingDependencies, Configuration actionConf,
076            boolean stopOnFirstMissing) throws CommandException {
077        return checkForAvailability(Arrays.asList(dependenciesAsArray(missingDependencies)), actionConf, stopOnFirstMissing);
078    }
079
080    /**
081     * Get the currently missing and available dependencies after checking the list of known missing
082     * dependencies against the source.
083     *
084     * @param missingDependencies known missing dependencies
085     * @param actionConf Configuration for the action
086     * @param stopOnFirstMissing Does not continue check for the rest of list if there is a missing
087     *        dependency
088     * @return ActionDependency which has the list of missing and available dependencies
089     * @throws CommandException in case of error
090     */
091    public static ActionDependency checkForAvailability(List<String> missingDependencies, Configuration actionConf,
092            boolean stopOnFirstMissing) throws CommandException {
093        final XLog LOG = XLog.getLog(DependencyChecker.class); //OOZIE-1251. Don't initialize as static variable.
094        String user = ParamChecker.notEmpty(actionConf.get(OozieClient.USER_NAME), OozieClient.USER_NAME);
095        List<String> missingDeps = new ArrayList<String>();
096        List<String> availableDeps = new ArrayList<String>();
097        URIHandlerService uriService = Services.get().get(URIHandlerService.class);
098        boolean continueChecking = true;
099        try {
100            for (int index = 0; index < missingDependencies.size(); index++) {
101                if (continueChecking) {
102                    String dependency = missingDependencies.get(index);
103
104                    URI uri = new URI(dependency);
105                    URIHandler uriHandler = uriService.getURIHandler(uri);
106                    LOG.debug("Checking for the availability of dependency [{0}] ", dependency);
107                    if (uriHandler.exists(uri, actionConf, user)) {
108                        LOG.debug("Dependency [{0}] is available", dependency);
109                        availableDeps.add(dependency);
110                    }
111                    else {
112                        LOG.debug("Dependency [{0}] is missing", dependency);
113                        missingDeps.add(dependency);
114                        if (stopOnFirstMissing) {
115                            continueChecking = false;
116                        }
117                    }
118
119                }
120                else {
121                    missingDeps.add(missingDependencies.get(index));
122                }
123            }
124        }
125        catch (URISyntaxException e) {
126            throw new CommandException(ErrorCode.E0906, e.getMessage(), e);
127        }
128        catch (URIHandlerException e) {
129            throw new CommandException(e);
130        }
131        return new ActionDependency(missingDeps, availableDeps);
132    }
133}