Java tutorial
/** * 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.oozie.action.hadoop; import org.apache.hadoop.hive.conf.HiveConf; import org.apache.hadoop.hive.metastore.api.MetaException; import org.apache.hadoop.io.Text; import org.apache.hadoop.mapred.JobConf; import org.apache.hadoop.mapreduce.security.token.delegation.DelegationTokenIdentifier; import org.apache.hadoop.security.UserGroupInformation; import org.apache.hadoop.security.token.Token; import org.apache.hadoop.security.SaslRpcServer; import org.apache.hive.hcatalog.api.HCatClient; import org.apache.hive.hcatalog.common.HCatException; import org.apache.oozie.util.XLog; /** * Helper class to handle the HCat credentials * Performs internally the heavy-lifting of fetching delegation tokens from Hive Metastore, abstracted from the user * Token is added to jobConf */ public class HCatCredentialHelper { private static final String USER_NAME = "user.name"; // Some Hive Metastore properties private static final String HIVE_METASTORE_SASL_ENABLED = "hive.metastore.sasl.enabled"; private static final String HIVE_METASTORE_KERBEROS_PRINCIPAL = "hive.metastore.kerberos.principal"; private static final String HIVE_METASTORE_LOCAL = "hive.metastore.local"; private static final String HADOOP_RPC_PROTECTION = "hadoop.rpc.protection"; /** * This Function will set the HCat token to jobconf * @param launcherJobConf - job conf * @param principal - principal for HCat server * @param server - Serevr URI for HCat server * @throws Exception */ public void set(JobConf launcherJobConf, String principal, String server) throws Exception { try { HCatClient client = getHCatClient(launcherJobConf, principal, server); XLog.getLog(getClass()) .debug("HCatCredentialHelper: set: User name for which token will be asked from HCat: " + launcherJobConf.get(USER_NAME)); String tokenStrForm = client.getDelegationToken(launcherJobConf.get(USER_NAME), UserGroupInformation.getLoginUser().getShortUserName()); Token<DelegationTokenIdentifier> hcatToken = new Token<DelegationTokenIdentifier>(); hcatToken.decodeFromUrlString(tokenStrForm); launcherJobConf.getCredentials().addToken(new Text("HCat Token"), hcatToken); XLog.getLog(getClass()).debug("Added the HCat token in job conf"); } catch (Exception ex) { XLog.getLog(getClass()).debug("set Exception" + ex.getMessage()); throw ex; } } /** * Getting the HCat client. * @param launcherJobConf * @param principal * @param server * @return HCatClient * @throws HCatException */ public HCatClient getHCatClient(JobConf launcherJobConf, String principal, String server) throws HCatException { HiveConf hiveConf = null; HCatClient hiveclient = null; hiveConf = new HiveConf(); XLog.getLog(getClass()).debug("getHCatClient: Principal: " + principal + " Server: " + server); // specified a thrift url hiveConf.set(HIVE_METASTORE_SASL_ENABLED, "true"); hiveConf.set(HIVE_METASTORE_KERBEROS_PRINCIPAL, principal); hiveConf.set(HIVE_METASTORE_LOCAL, "false"); hiveConf.set(HiveConf.ConfVars.METASTOREURIS.varname, server); String protection = launcherJobConf.get(HADOOP_RPC_PROTECTION, SaslRpcServer.QualityOfProtection.AUTHENTICATION.name().toLowerCase()); XLog.getLog(getClass()).debug("getHCatClient, setting rpc protection to " + protection); hiveConf.set(HADOOP_RPC_PROTECTION, protection); hiveclient = HCatClient.create(hiveConf); return hiveclient; } }