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 */
018package org.apache.hadoop.hbase.client;
019
020import java.io.IOException;
021import java.net.UnknownHostException;
022import java.util.Set;
023import java.util.concurrent.CompletableFuture;
024import java.util.stream.Collectors;
025import org.apache.commons.lang3.StringUtils;
026import org.apache.hadoop.conf.Configuration;
027import org.apache.hadoop.hbase.HBaseInterfaceAudience;
028import org.apache.hadoop.hbase.ServerName;
029import org.apache.hadoop.hbase.security.User;
030import org.apache.yetus.audience.InterfaceAudience;
031
032import org.apache.hbase.thirdparty.com.google.common.base.Splitter;
033
034import org.apache.hadoop.hbase.shaded.protobuf.ProtobufUtil;
035import org.apache.hadoop.hbase.shaded.protobuf.generated.RegistryProtos.ClientMetaService;
036import org.apache.hadoop.hbase.shaded.protobuf.generated.RegistryProtos.GetBootstrapNodesRequest;
037import org.apache.hadoop.hbase.shaded.protobuf.generated.RegistryProtos.GetBootstrapNodesResponse;
038
039/**
040 * Rpc based connection registry. It will make use of the {@link ClientMetaService} to get registry
041 * information.
042 * <p/>
043 * It needs bootstrap node list when start up, and then it will use {@link ClientMetaService} to
044 * refresh the bootstrap node list periodically.
045 * <p/>
046 * Usually, you could set masters as the bootstrap nodes,as they will also implement the
047 * {@link ClientMetaService}, and then, we will switch to use region servers after refreshing the
048 * bootstrap nodes.
049 */
050@InterfaceAudience.LimitedPrivate(HBaseInterfaceAudience.CONFIG)
051public class RpcConnectionRegistry extends AbstractRpcBasedConnectionRegistry {
052
053  /** Configuration key that controls the fan out of requests **/
054  public static final String HEDGED_REQS_FANOUT_KEY = "hbase.client.bootstrap.hedged.fanout";
055
056  /**
057   * As end users could configure any nodes in a cluster as the initial bootstrap nodes, it is
058   * possible that different end users will configure the same machine which makes the machine over
059   * load. So we should have a shorter delay for the initial refresh, to let users quickly switch to
060   * the bootstrap nodes we want them to connect to.
061   * <p/>
062   * The default value for initial refresh delay is 1/10 of periodic refresh interval.
063   */
064  public static final String INITIAL_REFRESH_DELAY_SECS =
065    "hbase.client.bootstrap.initial_refresh_delay_secs";
066
067  public static final String PERIODIC_REFRESH_INTERVAL_SECS =
068    "hbase.client.bootstrap.refresh_interval_secs";
069
070  public static final String MIN_SECS_BETWEEN_REFRESHES =
071    "hbase.client.bootstrap.min_secs_between_refreshes";
072
073  public static final String BOOTSTRAP_NODES = "hbase.client.bootstrap.servers";
074
075  private static final char ADDRS_CONF_SEPARATOR = ',';
076
077  private final String connectionString;
078
079  RpcConnectionRegistry(Configuration conf, User user) throws IOException {
080    super(conf, user, HEDGED_REQS_FANOUT_KEY, INITIAL_REFRESH_DELAY_SECS,
081      PERIODIC_REFRESH_INTERVAL_SECS, MIN_SECS_BETWEEN_REFRESHES);
082    connectionString = buildConnectionString(conf);
083  }
084
085  private String buildConnectionString(Configuration conf) throws UnknownHostException {
086    final String configuredBootstrapNodes = conf.get(BOOTSTRAP_NODES);
087    if (StringUtils.isBlank(configuredBootstrapNodes)) {
088      return MasterRegistry.getConnectionString(conf);
089    }
090    return Splitter.on(ADDRS_CONF_SEPARATOR).trimResults().splitToStream(configuredBootstrapNodes)
091      .collect(Collectors.joining(String.valueOf(ADDRS_CONF_SEPARATOR)));
092  }
093
094  @Override
095  protected Set<ServerName> getBootstrapNodes(Configuration conf) throws IOException {
096    // try get bootstrap nodes config first
097    String configuredBootstrapNodes = conf.get(BOOTSTRAP_NODES);
098    if (!StringUtils.isBlank(configuredBootstrapNodes)) {
099      return Splitter.on(ADDRS_CONF_SEPARATOR).trimResults().splitToStream(configuredBootstrapNodes)
100        .map(addr -> ServerName.valueOf(addr, ServerName.NON_STARTCODE))
101        .collect(Collectors.toSet());
102    } else {
103      // otherwise, just use master addresses
104      return MasterRegistry.parseMasterAddrs(conf);
105    }
106  }
107
108  @Override
109  public String getConnectionString() {
110    return connectionString;
111  }
112
113  private static Set<ServerName> transformServerNames(GetBootstrapNodesResponse resp) {
114    return resp.getServerNameList().stream().map(ProtobufUtil::toServerName)
115      .collect(Collectors.toSet());
116  }
117
118  private CompletableFuture<Set<ServerName>> getBootstrapNodes() {
119    return this
120      .<GetBootstrapNodesResponse> call(
121        (c, s, d) -> s.getBootstrapNodes(c, GetBootstrapNodesRequest.getDefaultInstance(), d),
122        r -> r.getServerNameCount() != 0, "getBootstrapNodes()")
123      .thenApply(RpcConnectionRegistry::transformServerNames);
124  }
125
126  @Override
127  protected CompletableFuture<Set<ServerName>> fetchEndpoints() {
128    return getBootstrapNodes();
129  }
130}