/**
*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.hadoop.hbase.zookeeper;
import java.io.IOException;
import java.io.InputStream;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.ArrayList;
import java.util.List;
import java.util.Properties;
import java.util.Map.Entry;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HConstants;
import org.apache.hadoop.util.StringUtils;
/**
* Utility methods for reading, parsing, and building zookeeper configuration.
*/
@InterfaceAudience.Public
@InterfaceStability.Evolving
public class ZKConfig {
private static final Log LOG = LogFactory.getLog(ZKConfig.class);
private static final String VARIABLE_START = "${";
private static final int VARIABLE_START_LENGTH = VARIABLE_START.length();
private static final String VARIABLE_END = "}";
private static final int VARIABLE_END_LENGTH = VARIABLE_END.length();
/**
* Make a Properties object holding ZooKeeper config equivalent to zoo.cfg.
* If there is a zoo.cfg in the classpath, simply read it in. Otherwise parse
* the corresponding config options from the HBase XML configs and generate
* the appropriate ZooKeeper properties.
* @param conf Configuration to read from.
* @return Properties holding mappings representing ZooKeeper zoo.cfg file.
*/
public static Properties makeZKProps(Configuration conf) {
// First check if there is a zoo.cfg in the CLASSPATH. If so, simply read
// it and grab its configuration properties.
ClassLoader cl = HQuorumPeer.class.getClassLoader();
final InputStream inputStream =
cl.getResourceAsStream(HConstants.ZOOKEEPER_CONFIG_NAME);
if (inputStream != null) {
try {
return parseZooCfg(conf, inputStream);
} catch (IOException e) {
LOG.warn("Cannot read " + HConstants.ZOOKEEPER_CONFIG_NAME +
", loading from XML files", e);
}
}
// Otherwise, use the configuration options from HBase's XML files.
Properties zkProperties = new Properties();
// Directly map all of the hbase.zookeeper.property.KEY properties.
for (Entry<String, String> entry : conf) {
String key = entry.getKey();
if (key.startsWith(HConstants.ZK_CFG_PROPERTY_PREFIX)) {
String zkKey = key.substring(HConstants.ZK_CFG_PROPERTY_PREFIX_LEN);
String value = entry.getValue();
// If the value has variables substitutions, need to do a get.
if (value.contains(VARIABLE_START)) {
value = conf.get(key);
}
zkProperties.put(zkKey, value);
}
}
// If clientPort is not set, assign the default.
if (zkProperties.getProperty(HConstants.CLIENT_PORT_STR) == null) {
zkProperties.put(HConstants.CLIENT_PORT_STR,
HConstants.DEFAULT_ZOOKEPER_CLIENT_PORT);
}
// Create the server.X properties.
int peerPort = conf.getInt("hbase.zookeeper.peerport", 2888);
int leaderPort = conf.getInt("hbase.zookeeper.leaderport", 3888);
final String[] serverHosts = conf.getStrings(HConstants.ZOOKEEPER_QUORUM,
HConstants.LOCALHOST);
for (int i = 0; i < serverHosts.length; ++i) {
String serverHost = serverHosts[i];
String address = serverHost + ":" + peerPort + ":" + leaderPort;
String key = "server." + i;
zkProperties.put(key, address);
}
return zkProperties;
}
/**
* Parse ZooKeeper's zoo.cfg, injecting HBase Configuration variables in.
* This method is used for testing so we can pass our own InputStream.
* @param conf HBaseConfiguration to use for injecting variables.
* @param inputStream InputStream to read from.
* @return Properties parsed from config stream with variables substituted.
* @throws IOException if anything goes wrong parsing config
*/
public static Properties parseZooCfg(Configuration conf,
InputStream inputStream) throws IOException {
Properties properties = new Properties();
try {
properties.load(inputStream);
} catch (IOException e) {
final String msg = "fail to read properties from "
+ HConstants.ZOOKEEPER_CONFIG_NAME;
LOG.fatal(msg);
throw new IOException(msg, e);
}
for (Entry<Object, Object> entry : properties.entrySet()) {
String value = entry.getValue().toString().trim();
String key = entry.getKey().toString().trim();
StringBuilder newValue = new StringBuilder();
int varStart = value.indexOf(VARIABLE_START);
int varEnd = 0;
while (varStart != -1) {
varEnd = value.indexOf(VARIABLE_END, varStart);
if (varEnd == -1) {
String msg = "variable at " + varStart + " has no end marker";
LOG.fatal(msg);
throw new IOException(msg);
}
String variable = value.substring(varStart + VARIABLE_START_LENGTH, varEnd);
String substituteValue = System.getProperty(variable);
if (substituteValue == null) {
substituteValue = conf.get(variable);
}
if (substituteValue == null) {
String msg = "variable " + variable + " not set in system property "
+ "or hbase configs";
LOG.fatal(msg);
throw new IOException(msg);
}
newValue.append(substituteValue);
varEnd += VARIABLE_END_LENGTH;
varStart = value.indexOf(VARIABLE_START, varEnd);
}
// Special case for 'hbase.cluster.distributed' property being 'true'
if (key.startsWith("server.")) {
boolean mode = conf.getBoolean(HConstants.CLUSTER_DISTRIBUTED, HConstants.DEFAULT_CLUSTER_DISTRIBUTED);
if (mode == HConstants.CLUSTER_IS_DISTRIBUTED && value.startsWith(HConstants.LOCALHOST)) {
String msg = "The server in zoo.cfg cannot be set to localhost " +
"in a fully-distributed setup because it won't be reachable. " +
"See \"Getting Started\" for more information.";
LOG.fatal(msg);
throw new IOException(msg);
}
}
newValue.append(value.substring(varEnd));
properties.setProperty(key, newValue.toString());
}
return properties;
}
/**
* Return the ZK Quorum servers string given zk properties returned by
* makeZKProps
* @param properties
* @return Quorum servers String
*/
public static String getZKQuorumServersString(Properties properties) {
String clientPort = null;
List<String> servers = new ArrayList<String>();
// The clientPort option may come after the server.X hosts, so we need to
// grab everything and then create the final host:port comma separated list.
boolean anyValid = false;
for (Entry<Object,Object> property : properties.entrySet()) {
String key = property.getKey().toString().trim();
String value = property.getValue().toString().trim();
if (key.equals("clientPort")) {
clientPort = value;
}
else if (key.startsWith("server.")) {
String host = value.substring(0, value.indexOf(':'));
servers.add(host);
try {
//noinspection ResultOfMethodCallIgnored
InetAddress.getByName(host);
anyValid = true;
} catch (UnknownHostException e) {
LOG.warn(StringUtils.stringifyException(e));
}
}
}
if (!anyValid) {
LOG.error("no valid quorum servers found in " + HConstants.ZOOKEEPER_CONFIG_NAME);
return null;
}
if (clientPort == null) {
LOG.error("no clientPort found in " + HConstants.ZOOKEEPER_CONFIG_NAME);
return null;
}
if (servers.isEmpty()) {
LOG.fatal("No server.X lines found in conf/zoo.cfg. HBase must have a " +
"ZooKeeper cluster configured for its operation.");
return null;
}
StringBuilder hostPortBuilder = new StringBuilder();
for (int i = 0; i < servers.size(); ++i) {
String host = servers.get(i);
if (i > 0) {
hostPortBuilder.append(',');
}
hostPortBuilder.append(host);
hostPortBuilder.append(':');
hostPortBuilder.append(clientPort);
}
return hostPortBuilder.toString();
}
/**
* Return the ZK Quorum servers string given the specified configuration.
* @param conf
* @return Quorum servers
*/
public static String getZKQuorumServersString(Configuration conf) {
return getZKQuorumServersString(makeZKProps(conf));
}
}