org.apache.accumulo.hadoopImpl.mapreduce.lib.MapReduceClientOpts.java Source code

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Here is the source code for org.apache.accumulo.hadoopImpl.mapreduce.lib.MapReduceClientOpts.java

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/*
 * 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.accumulo.hadoopImpl.mapreduce.lib;

import java.io.IOException;
import java.util.Properties;

import org.apache.accumulo.core.cli.ClientOpts;
import org.apache.accumulo.core.client.Accumulo;
import org.apache.accumulo.core.client.AccumuloClient;
import org.apache.accumulo.core.client.AccumuloException;
import org.apache.accumulo.core.client.AccumuloSecurityException;
import org.apache.accumulo.core.client.admin.DelegationTokenConfig;
import org.apache.accumulo.core.client.security.tokens.AuthenticationToken;
import org.apache.accumulo.core.client.security.tokens.KerberosToken;
import org.apache.accumulo.core.conf.ClientProperty;
import org.apache.accumulo.core.security.SystemPermission;
import org.apache.hadoop.security.UserGroupInformation;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Adds some MR awareness to the ClientOpts
 */
public class MapReduceClientOpts extends ClientOpts {

    private static final Logger log = LoggerFactory.getLogger(MapReduceClientOpts.class);

    public Properties getClientProps() {
        Properties props = super.getClientProps();
        // For MapReduce, Kerberos credentials don't make it to the Mappers and Reducers,
        // so we need to request a delegation token and use that instead.
        AuthenticationToken authToken = ClientProperty.getAuthenticationToken(props);
        if (authToken instanceof KerberosToken) {
            log.info("Received KerberosToken, fetching DelegationToken for MapReduce");
            final KerberosToken krbToken = (KerberosToken) authToken;

            try {
                UserGroupInformation user = UserGroupInformation.getCurrentUser();
                if (!user.hasKerberosCredentials()) {
                    throw new IllegalStateException("Expected current user to have Kerberos credentials");
                }

                String newPrincipal = user.getUserName();
                log.info("Obtaining delegation token for {}", newPrincipal);

                try (AccumuloClient client = Accumulo.newClient().from(props).as(newPrincipal, krbToken).build()) {

                    // Do the explicit check to see if the user has the permission to get a delegation token
                    if (!client.securityOperations().hasSystemPermission(client.whoami(),
                            SystemPermission.OBTAIN_DELEGATION_TOKEN)) {
                        log.error(
                                "{} doesn't have the {} SystemPermission neccesary to obtain a delegation"
                                        + " token. MapReduce tasks cannot automatically use the client's"
                                        + " credentials on remote servers. Delegation tokens provide a means to run"
                                        + " MapReduce without distributing the user's credentials.",
                                user.getUserName(), SystemPermission.OBTAIN_DELEGATION_TOKEN.name());
                        throw new IllegalStateException(
                                client.whoami() + " does not have permission to obtain a delegation token");
                    }

                    // Get the delegation token from Accumulo
                    AuthenticationToken token = client.securityOperations()
                            .getDelegationToken(new DelegationTokenConfig());

                    props.setProperty(ClientProperty.AUTH_PRINCIPAL.getKey(), newPrincipal);
                    ClientProperty.setAuthenticationToken(props, token);
                }
            } catch (IOException | AccumuloException | AccumuloSecurityException e) {
                final String msg = "Failed to acquire DelegationToken for use with MapReduce";
                log.error(msg, e);
                throw new RuntimeException(msg, e);
            }
        }
        return props;
    }
}