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.service;
020
021import java.io.IOException;
022import java.util.concurrent.ConcurrentHashMap;
023import java.util.concurrent.ConcurrentMap;
024import org.apache.hadoop.fs.FileSystem;
025
026import org.apache.hadoop.security.UserGroupInformation;
027import org.apache.oozie.util.XLog;
028
029public class UserGroupInformationService implements Service {
030
031    private ConcurrentMap<String, UserGroupInformation> cache = new ConcurrentHashMap<String, UserGroupInformation>();
032
033    @Override
034    public void init(Services services) throws ServiceException {
035    }
036
037    @Override
038    public void destroy() {
039        for (UserGroupInformation ugi : cache.values()) {
040            try {
041                FileSystem.closeAllForUGI(ugi);
042            } catch(IOException ioe) {
043                XLog.getLog(this.getClass()).warn("Exception occurred while closing filesystems for " + ugi.getUserName(), ioe);
044            }
045        }
046        cache.clear();
047    }
048
049    @Override
050    public Class<? extends Service> getInterface() {
051        return UserGroupInformationService.class;
052    }
053
054    public UserGroupInformation getProxyUser(String user) throws IOException {
055        cache.putIfAbsent(user, UserGroupInformation.createProxyUser(user, UserGroupInformation.getLoginUser()));
056        return cache.get(user);
057    }
058
059}