org.apache.hive.service.cli.session.SessionUtils.java Source code

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Here is the source code for org.apache.hive.service.cli.session.SessionUtils.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.hive.service.cli.session;

import java.io.IOException;

import org.apache.hadoop.hive.metastore.security.DelegationTokenIdentifier;
import org.apache.hadoop.hive.metastore.security.DelegationTokenSelector;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.security.UserGroupInformation;
import org.apache.hadoop.security.token.Token;
import org.apache.hadoop.security.token.TokenIdentifier;
import org.apache.hadoop.security.token.TokenSelector;

public class SessionUtils {
    /**
     * Get the string form of the token given a token signature. The signature is used as the value of
     * the "service" field in the token for lookup. Ref: AbstractDelegationTokenSelector in Hadoop. If
     * there exists such a token in the token cache (credential store) of the job, the lookup returns
     * that. This is relevant only when running against a "secure" hadoop release The method gets hold
     * of the tokens if they are set up by hadoop - this should happen on the map/reduce tasks if the
     * client added the tokens into hadoop's credential store in the front end during job submission.
     * The method will select the hive delegation token among the set of tokens and return the string
     * form of it
     * 
     * @param tokenSignature
     * @return the string form of the token found
     * @throws IOException
     */
    public static String getTokenStrForm(String tokenSignature) throws IOException {
        UserGroupInformation ugi = UserGroupInformation.getCurrentUser();
        TokenSelector<? extends TokenIdentifier> tokenSelector = new DelegationTokenSelector();

        Token<? extends TokenIdentifier> token = tokenSelector
                .selectToken(tokenSignature == null ? new Text() : new Text(tokenSignature), ugi.getTokens());
        return token != null ? token.encodeToUrlString() : null;
    }

    /**
     * Create a delegation token object for the given token string and service. Add the token to given
     * UGI
     * 
     * @param ugi
     * @param tokenStr
     * @param tokenService
     * @throws IOException
     */
    public static void setTokenStr(UserGroupInformation ugi, String tokenStr, String tokenService)
            throws IOException {
        Token<DelegationTokenIdentifier> delegationToken = createToken(tokenStr, tokenService);
        ugi.addToken(delegationToken);
    }

    /**
     * Add a given service to delegation token string.
     * 
     * @param tokenStr
     * @param tokenService
     * @return
     * @throws IOException
     */
    public static String addServiceToToken(String tokenStr, String tokenService) throws IOException {
        Token<DelegationTokenIdentifier> delegationToken = createToken(tokenStr, tokenService);
        return delegationToken.encodeToUrlString();
    }

    /**
     * Create a new token using the given string and service
     * 
     * @param tokenStr
     * @param tokenService
     * @return
     * @throws IOException
     */
    private static Token<DelegationTokenIdentifier> createToken(String tokenStr, String tokenService)
            throws IOException {
        Token<DelegationTokenIdentifier> delegationToken = new Token<DelegationTokenIdentifier>();
        delegationToken.decodeFromUrlString(tokenStr);
        delegationToken.setService(new Text(tokenService));
        return delegationToken;
    }
}