/** 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.mapreduce.security;

import static org.assertj.core.api.Assertions.assertThat;
import static org.junit.Assert.fail;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.net.URI;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.hdfs.DFSUtilClient;
import org.apache.hadoop.hdfs.MiniDFSCluster;
import org.apache.hadoop.hdfs.server.namenode.NameNode;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.MiniMRClientCluster;
import org.apache.hadoop.mapred.MiniMRClientClusterFactory;
import org.apache.hadoop.mapreduce.JobContext;
import org.apache.hadoop.util.ToolRunner;
import org.junit.AfterClass;
import org.junit.BeforeClass;
import org.junit.Test;

/**
 * Tests whether a protected secret passed from JobClient is
 * available to the child task
 */

public class TestMRCredentials {

  static final int NUM_OF_KEYS = 10;
  private static MiniMRClientCluster mrCluster;
  private static MiniDFSCluster dfsCluster;
  private static int numWorkers = 1;
  private static JobConf jConf;

  @SuppressWarnings("deprecation")
  @BeforeClass
  public static void setUp() throws Exception {
    System.setProperty("hadoop.log.dir", "logs");
    Configuration conf = new Configuration();
    dfsCluster = new MiniDFSCluster.Builder(conf).numDataNodes(numWorkers)
        .build();
    jConf = new JobConf(conf);
    FileSystem.setDefaultUri(conf, dfsCluster.getFileSystem().getUri().toString());
    mrCluster = MiniMRClientClusterFactory.create(TestMRCredentials.class, 1, jConf);
    createKeysAsJson("keys.json");
  }

  @AfterClass
  public static void tearDown() throws Exception {
    if(mrCluster != null)
      mrCluster.stop();
    mrCluster = null;
    if(dfsCluster != null)
      dfsCluster.shutdown();
    dfsCluster = null;

    new File("keys.json").delete();

  }

  public static void createKeysAsJson(String fileName)
  throws FileNotFoundException, IOException{
    StringBuilder jsonString = new StringBuilder();
    jsonString.append("{");
    for(int i=0; i<NUM_OF_KEYS; i++) {
      String keyName = "alias"+i;
      String password = "password"+i;
      jsonString.append("\""+ keyName +"\":"+ "\""+password+"\"" );
      if (i < (NUM_OF_KEYS-1)){
        jsonString.append(",");
      }

    }
    jsonString.append("}");

    FileOutputStream fos= new FileOutputStream (fileName);
    fos.write(jsonString.toString().getBytes());
    fos.close();
  }


  /**
   * run a distributed job and verify that TokenCache is available
   * @throws IOException
   */
  @Test
  public void test () throws IOException {

    // make sure JT starts
    Configuration jobConf =  new JobConf(mrCluster.getConfig());

    // provide namenodes names for the job to get the delegation tokens for
    NameNode nn = dfsCluster.getNameNode();
    URI nnUri = DFSUtilClient.getNNUri(nn.getNameNodeAddress());
    jobConf.set(JobContext.JOB_NAMENODES, nnUri + "," + nnUri.toString());


    jobConf.set("mapreduce.job.credentials.json" , "keys.json");

    // using argument to pass the file name
    String[] args = {
        "-m", "1", "-r", "1", "-mt", "1", "-rt", "1"
    };

    int res = -1;
    try {
      res = ToolRunner.run(jobConf, new CredentialsTestJob(), args);
    } catch (Exception e) {
      System.out.println("Job failed with" + e.getLocalizedMessage());
      e.printStackTrace(System.out);
      fail("Job failed");
    }
    assertThat(res).withFailMessage("dist job res is not 0").isEqualTo(0);

  }
}
