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.reef.bridge.client; import org.apache.avro.io.BinaryDecoder; import org.apache.avro.io.DecoderFactory; import org.apache.avro.io.DatumReader; import org.apache.avro.specific.SpecificDatumReader; 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.reef.runtime.common.files.REEFFileNames; import javax.inject.Inject; import java.io.File; import java.io.FileInputStream; import java.io.IOException; import java.util.logging.Level; import java.util.logging.Logger; /** * Helper class to read security tokens from file and add them to the user's credentials. * .Net SecurityTokenWriter stores the token info in a file and passes it to the java client. * The method in this class will read this data and add tokens to UserGroupInformation. */ final class SecurityTokensReader { private static final Logger LOG = Logger.getLogger(SecurityTokensReader.class.getName()); private final DatumReader<SecurityToken> tokenDatumReader = new SpecificDatumReader<>(SecurityToken.class); private final DecoderFactory decoderFactory = new DecoderFactory(); private final File securityTokensFile; @Inject private SecurityTokensReader(final REEFFileNames reefFileNames) { this.securityTokensFile = new File(reefFileNames.getSecurityTokensFile()); } /** * Read tokens from a file and add them to the user's credentials. * @param ugi user's credentials to add tokens to. * @throws IOException if there are errors in reading the tokens' file. */ void addTokensFromFile(final UserGroupInformation ugi) throws IOException { LOG.log(Level.FINE, "Reading security tokens from file: {0}", this.securityTokensFile); try (final FileInputStream stream = new FileInputStream(securityTokensFile)) { final BinaryDecoder decoder = decoderFactory.binaryDecoder(stream, null); while (!decoder.isEnd()) { final SecurityToken token = tokenDatumReader.read(null, decoder); final Token<TokenIdentifier> yarnToken = new Token<>(token.getKey().array(), token.getPassword().array(), new Text(token.getKind().toString()), new Text(token.getService().toString())); LOG.log(Level.FINE, "addToken for {0}", yarnToken.getKind()); ugi.addToken(yarnToken); } } } }