org.apache.hadoop.dfs.TestDataTransferProtocol.java Source code

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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.hadoop.dfs;

import junit.framework.TestCase;
import java.io.*;
import java.util.Random;
import java.net.InetSocketAddress;
import java.net.Socket;
import java.nio.ByteBuffer;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.io.IOUtils;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.net.NetUtils;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.dfs.DFSClient.DFSDataInputStream;
import org.apache.hadoop.dfs.FSConstants.DatanodeReportType;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * This tests data transfer protocol handling in the Datanode. It sends
 * various forms of wrong data and verifies that Datanode handles it well.
 */
public class TestDataTransferProtocol extends TestCase {

    private static final Log LOG = LogFactory.getLog("org.apache.hadoop.dfs.TestDataTransferProtocol");

    DatanodeID datanode;
    InetSocketAddress dnAddr;
    ByteArrayOutputStream sendBuf = new ByteArrayOutputStream(128);
    DataOutputStream sendOut = new DataOutputStream(sendBuf);
    // byte[] recvBuf = new byte[128];
    // ByteBuffer recvByteBuf = ByteBuffer.wrap(recvBuf);
    ByteArrayOutputStream recvBuf = new ByteArrayOutputStream(128);
    DataOutputStream recvOut = new DataOutputStream(recvBuf);

    private void sendRecvData(String testDescription, boolean eofExpected) throws IOException {
        /* Opens a socket to datanode
         * sends the data in sendBuf.
         * If there is data in expectedBuf, expects to receive the data
         *     from datanode that matches expectedBuf.
         * If there is an exception while recieving, throws it
         *     only if exceptionExcepted is false.
         */

        Socket sock = null;
        try {

            if (testDescription != null) {
                LOG.info("Testing : " + testDescription);
            }
            sock = new Socket();
            sock.connect(dnAddr, FSConstants.READ_TIMEOUT);
            sock.setSoTimeout(FSConstants.READ_TIMEOUT);

            OutputStream out = sock.getOutputStream();
            // Should we excuse 
            byte[] retBuf = new byte[recvBuf.size()];

            DataInputStream in = new DataInputStream(sock.getInputStream());
            out.write(sendBuf.toByteArray());
            try {
                in.readFully(retBuf);
            } catch (EOFException eof) {
                if (eofExpected) {
                    LOG.info("Got EOF as expected.");
                    return;
                }
                throw eof;
            }
            for (int i = 0; i < retBuf.length; i++) {
                System.out.print(retBuf[i]);
            }
            System.out.println(":");

            if (eofExpected) {
                throw new IOException("Did not recieve IOException when an exception "
                        + "is expected while reading from " + datanode.getName());
            }

            byte[] needed = recvBuf.toByteArray();
            for (int i = 0; i < retBuf.length; i++) {
                System.out.print(retBuf[i]);
                assertEquals("checking byte[" + i + "]", needed[i], retBuf[i]);
            }
        } finally {
            IOUtils.closeSocket(sock);
        }
    }

    void createFile(FileSystem fs, Path path, int fileLen) throws IOException {
        byte[] arr = new byte[fileLen];
        FSDataOutputStream out = fs.create(path);
        out.write(arr);
        out.close();
    }

    void readFile(FileSystem fs, Path path, int fileLen) throws IOException {
        byte[] arr = new byte[fileLen];
        FSDataInputStream in = fs.open(path);
        in.readFully(arr);
    }

    public void testDataTransferProtocol() throws IOException {
        Random random = new Random();
        int oneMil = 1024 * 1024;
        Path file = new Path("dataprotocol.dat");
        int numDataNodes = 1;

        Configuration conf = new Configuration();
        conf.setInt("dfs.replication", numDataNodes);
        MiniDFSCluster cluster = new MiniDFSCluster(conf, numDataNodes, true, null);
        cluster.waitActive();
        DFSClient dfsClient = new DFSClient(new InetSocketAddress("localhost", cluster.getNameNodePort()), conf);
        datanode = dfsClient.datanodeReport(DatanodeReportType.LIVE)[0];
        dnAddr = NetUtils.createSocketAddr(datanode.getName());
        FileSystem fileSys = cluster.getFileSystem();

        int fileLen = Math.min(conf.getInt("dfs.block.size", 4096), 4096);

        createFile(fileSys, file, fileLen);

        // get the first blockid for the file
        Block firstBlock = DFSTestUtil.getFirstBlock(fileSys, file);
        long newBlockId = firstBlock.getBlockId() + 1;

        recvBuf.reset();
        sendBuf.reset();

        // bad version
        recvOut.writeShort((short) (FSConstants.DATA_TRANSFER_VERSION - 1));
        sendOut.writeShort((short) (FSConstants.DATA_TRANSFER_VERSION - 1));
        sendRecvData("Wrong Version", true);

        // bad ops
        sendBuf.reset();
        sendOut.writeShort((short) FSConstants.DATA_TRANSFER_VERSION);
        sendOut.writeByte((byte) (FSConstants.OP_WRITE_BLOCK - 1));
        sendRecvData("Wrong Op Code", true);

        /* Test OP_WRITE_BLOCK */
        sendBuf.reset();
        sendOut.writeShort((short) FSConstants.DATA_TRANSFER_VERSION);
        sendOut.writeByte((byte) FSConstants.OP_WRITE_BLOCK);
        sendOut.writeLong(newBlockId); // block id
        sendOut.writeLong(0); // generation stamp
        sendOut.writeInt(0); // targets in pipeline 
        sendOut.writeBoolean(false); // recoveryFlag
        Text.writeString(sendOut, "cl");// clientID
        sendOut.writeBoolean(false); // no src node info
        sendOut.writeInt(0); // number of downstream targets
        sendOut.writeByte((byte) DataChecksum.CHECKSUM_CRC32);

        // bad bytes per checksum
        sendOut.writeInt(-1 - random.nextInt(oneMil));
        recvBuf.reset();
        recvOut.writeShort((short) FSConstants.OP_STATUS_ERROR);
        sendRecvData("wrong bytesPerChecksum while writing", true);

        sendBuf.reset();
        recvBuf.reset();
        sendOut.writeShort((short) FSConstants.DATA_TRANSFER_VERSION);
        sendOut.writeByte((byte) FSConstants.OP_WRITE_BLOCK);
        sendOut.writeLong(newBlockId);
        sendOut.writeLong(0); // generation stamp
        sendOut.writeInt(0); // targets in pipeline 
        sendOut.writeBoolean(false); // recoveryFlag
        Text.writeString(sendOut, "cl");// clientID
        sendOut.writeBoolean(false); // no src node info

        // bad number of targets
        sendOut.writeInt(-1 - random.nextInt(oneMil));
        recvOut.writeShort((short) FSConstants.OP_STATUS_ERROR);
        sendRecvData("bad targets len while writing block " + newBlockId, true);

        sendBuf.reset();
        recvBuf.reset();
        sendOut.writeShort((short) FSConstants.DATA_TRANSFER_VERSION);
        sendOut.writeByte((byte) FSConstants.OP_WRITE_BLOCK);
        sendOut.writeLong(++newBlockId);
        sendOut.writeLong(0); // generation stamp
        sendOut.writeInt(0); // targets in pipeline 
        sendOut.writeBoolean(false); // recoveryFlag
        Text.writeString(sendOut, "cl");// clientID
        sendOut.writeBoolean(false); // no src node info
        sendOut.writeInt(0);
        sendOut.writeByte((byte) DataChecksum.CHECKSUM_CRC32);
        sendOut.writeInt((int) 512);
        sendOut.writeInt(4); // size of packet
        sendOut.writeLong(0); // OffsetInBlock
        sendOut.writeLong(100); // sequencenumber
        sendOut.writeBoolean(false); // lastPacketInBlock

        // bad data chunk length
        sendOut.writeInt(-1 - random.nextInt(oneMil));
        Text.writeString(recvOut, ""); // first bad node
        recvOut.writeLong(100); // sequencenumber
        recvOut.writeShort((short) FSConstants.OP_STATUS_ERROR);
        sendRecvData("negative DATA_CHUNK len while writing block " + newBlockId, true);

        // test for writing a valid zero size block
        sendBuf.reset();
        recvBuf.reset();
        sendOut.writeShort((short) FSConstants.DATA_TRANSFER_VERSION);
        sendOut.writeByte((byte) FSConstants.OP_WRITE_BLOCK);
        sendOut.writeLong(++newBlockId);
        sendOut.writeLong(0); // generation stamp
        sendOut.writeInt(0); // targets in pipeline 
        sendOut.writeBoolean(false); // recoveryFlag
        Text.writeString(sendOut, "cl");// clientID
        sendOut.writeBoolean(false); // no src node info
        sendOut.writeInt(0);
        sendOut.writeByte((byte) DataChecksum.CHECKSUM_CRC32);
        sendOut.writeInt((int) 512); // checksum size
        sendOut.writeInt(8); // size of packet
        sendOut.writeLong(0); // OffsetInBlock
        sendOut.writeLong(100); // sequencenumber
        sendOut.writeBoolean(true); // lastPacketInBlock

        sendOut.writeInt(0); // chunk length
        sendOut.writeInt(0); // zero checksum
        //ok finally write a block with 0 len
        Text.writeString(recvOut, ""); // first bad node
        recvOut.writeLong(100); // sequencenumber
        recvOut.writeShort((short) FSConstants.OP_STATUS_SUCCESS);
        sendRecvData("Writing a zero len block blockid " + newBlockId, false);

        /* Test OP_READ_BLOCK */

        // bad block id
        sendBuf.reset();
        recvBuf.reset();
        sendOut.writeShort((short) FSConstants.DATA_TRANSFER_VERSION);
        sendOut.writeByte((byte) FSConstants.OP_READ_BLOCK);
        newBlockId = firstBlock.getBlockId() - 1;
        sendOut.writeLong(newBlockId);
        sendOut.writeLong(firstBlock.getGenerationStamp());
        sendOut.writeLong(0L);
        sendOut.writeLong(fileLen);
        recvOut.writeShort((short) FSConstants.OP_STATUS_ERROR);
        sendRecvData("Wrong block ID " + newBlockId + " for read", false);

        // negative block start offset
        sendBuf.reset();
        sendOut.writeShort((short) FSConstants.DATA_TRANSFER_VERSION);
        sendOut.writeByte((byte) FSConstants.OP_READ_BLOCK);
        sendOut.writeLong(firstBlock.getBlockId());
        sendOut.writeLong(firstBlock.getGenerationStamp());
        sendOut.writeLong(-1L);
        sendOut.writeLong(fileLen);
        sendRecvData("Negative start-offset for read for block " + firstBlock.getBlockId(), false);

        // bad block start offset
        sendBuf.reset();
        sendOut.writeShort((short) FSConstants.DATA_TRANSFER_VERSION);
        sendOut.writeByte((byte) FSConstants.OP_READ_BLOCK);
        sendOut.writeLong(firstBlock.getBlockId());
        sendOut.writeLong(firstBlock.getGenerationStamp());
        sendOut.writeLong(fileLen);
        sendOut.writeLong(fileLen);
        sendRecvData("Wrong start-offset for reading block " + firstBlock.getBlockId(), false);

        // negative length is ok. Datanode assumes we want to read the whole block.
        recvBuf.reset();
        recvOut.writeShort((short) FSConstants.OP_STATUS_SUCCESS);
        sendBuf.reset();
        sendOut.writeShort((short) FSConstants.DATA_TRANSFER_VERSION);
        sendOut.writeByte((byte) FSConstants.OP_READ_BLOCK);
        sendOut.writeLong(firstBlock.getBlockId());
        sendOut.writeLong(firstBlock.getGenerationStamp());
        sendOut.writeLong(0);
        sendOut.writeLong(-1 - random.nextInt(oneMil));
        sendRecvData("Negative length for reading block " + firstBlock.getBlockId(), false);

        // length is more than size of block.
        recvBuf.reset();
        recvOut.writeShort((short) FSConstants.OP_STATUS_ERROR);
        sendBuf.reset();
        sendOut.writeShort((short) FSConstants.DATA_TRANSFER_VERSION);
        sendOut.writeByte((byte) FSConstants.OP_READ_BLOCK);
        sendOut.writeLong(firstBlock.getBlockId());
        sendOut.writeLong(firstBlock.getGenerationStamp());
        sendOut.writeLong(0);
        sendOut.writeLong(fileLen + 1);
        sendRecvData("Wrong length for reading block " + firstBlock.getBlockId(), false);

        //At the end of all this, read the file to make sure that succeeds finally.
        sendBuf.reset();
        sendOut.writeShort((short) FSConstants.DATA_TRANSFER_VERSION);
        sendOut.writeByte((byte) FSConstants.OP_READ_BLOCK);
        sendOut.writeLong(firstBlock.getBlockId());
        sendOut.writeLong(firstBlock.getGenerationStamp());
        sendOut.writeLong(0);
        sendOut.writeLong(fileLen);
        readFile(fileSys, file, fileLen);
    }
}