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.hadoop.hbase.rest;
020
021import java.io.IOException;
022
023import org.apache.hadoop.conf.Configuration;
024import org.apache.yetus.audience.InterfaceAudience;
025import org.slf4j.Logger;
026import org.slf4j.LoggerFactory;
027import org.apache.hadoop.hbase.client.Admin;
028import org.apache.hadoop.hbase.client.Table;
029import org.apache.hadoop.hbase.filter.ParseFilter;
030import org.apache.hadoop.hbase.security.UserProvider;
031import org.apache.hadoop.hbase.util.ConnectionCache;
032import org.apache.hadoop.hbase.util.JvmPauseMonitor;
033import org.apache.hadoop.security.UserGroupInformation;
034import org.apache.hadoop.security.authorize.ProxyUsers;
035
036/**
037 * Singleton class encapsulating global REST servlet state and functions.
038 */
039@InterfaceAudience.Private
040public class RESTServlet implements Constants {
041  private static final Logger LOG = LoggerFactory.getLogger(RESTServlet.class);
042  private static RESTServlet INSTANCE;
043  private final Configuration conf;
044  private final MetricsREST metrics;
045  private final ConnectionCache connectionCache;
046  private final UserGroupInformation realUser;
047  private final JvmPauseMonitor pauseMonitor;
048
049  static final String CLEANUP_INTERVAL = "hbase.rest.connection.cleanup-interval";
050  static final String MAX_IDLETIME = "hbase.rest.connection.max-idletime";
051  static final String HBASE_REST_SUPPORT_PROXYUSER = "hbase.rest.support.proxyuser";
052
053  UserGroupInformation getRealUser() {
054    return realUser;
055  }
056
057  /**
058   * @return the RESTServlet singleton instance
059   */
060  public synchronized static RESTServlet getInstance() {
061    assert(INSTANCE != null);
062    return INSTANCE;
063  }
064
065  /**
066   * @param conf Existing configuration to use in rest servlet
067   * @param userProvider the login user provider
068   * @return the RESTServlet singleton instance
069   * @throws IOException
070   */
071  public synchronized static RESTServlet getInstance(Configuration conf,
072      UserProvider userProvider) throws IOException {
073    if (INSTANCE == null) {
074      INSTANCE = new RESTServlet(conf, userProvider);
075    }
076    return INSTANCE;
077  }
078
079  public synchronized static void stop() {
080    if (INSTANCE != null) {
081      INSTANCE.shutdown();
082      INSTANCE = null;
083    }
084  }
085
086  /**
087   * Constructor with existing configuration
088   * @param conf existing configuration
089   * @param userProvider the login user provider
090   * @throws IOException
091   */
092  RESTServlet(final Configuration conf,
093      final UserProvider userProvider) throws IOException {
094    this.realUser = userProvider.getCurrent().getUGI();
095    this.conf = conf;
096    registerCustomFilter(conf);
097
098    int cleanInterval = conf.getInt(CLEANUP_INTERVAL, 10 * 1000);
099    int maxIdleTime = conf.getInt(MAX_IDLETIME, 10 * 60 * 1000);
100    connectionCache = new ConnectionCache(
101      conf, userProvider, cleanInterval, maxIdleTime);
102    if (supportsProxyuser()) {
103      ProxyUsers.refreshSuperUserGroupsConfiguration(conf);
104    }
105
106    metrics = new MetricsREST();
107
108    pauseMonitor = new JvmPauseMonitor(conf, metrics.getSource());
109    pauseMonitor.start();
110  }
111
112  Admin getAdmin() throws IOException {
113    return connectionCache.getAdmin();
114  }
115
116  /**
117   * Caller closes the table afterwards.
118   */
119  Table getTable(String tableName) throws IOException {
120    return connectionCache.getTable(tableName);
121  }
122
123  Configuration getConfiguration() {
124    return conf;
125  }
126
127  MetricsREST getMetrics() {
128    return metrics;
129  }
130
131  /**
132   * Helper method to determine if server should
133   * only respond to GET HTTP method requests.
134   * @return boolean for server read-only state
135   */
136  boolean isReadOnly() {
137    return getConfiguration().getBoolean("hbase.rest.readonly", false);
138  }
139
140  void setEffectiveUser(String effectiveUser) {
141    connectionCache.setEffectiveUser(effectiveUser);
142  }
143
144  /**
145   * Shutdown any services that need to stop
146   */
147  void shutdown() {
148    if (pauseMonitor != null) pauseMonitor.stop();
149    if (connectionCache != null) connectionCache.shutdown();
150  }
151
152  boolean supportsProxyuser() {
153    return conf.getBoolean(HBASE_REST_SUPPORT_PROXYUSER, false);
154  }
155
156  private void registerCustomFilter(Configuration conf) {
157    String[] filterList = conf.getStrings(Constants.CUSTOM_FILTERS);
158    if (filterList != null) {
159      for (String filterClass : filterList) {
160        String[] filterPart = filterClass.split(":");
161        if (filterPart.length != 2) {
162          LOG.warn(
163            "Invalid filter specification " + filterClass + " - skipping");
164        } else {
165          ParseFilter.registerFilter(filterPart[0], filterPart[1]);
166        }
167      }
168    }
169  }
170}