/**
* 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.hdfs;
import java.net.InetSocketAddress;
import java.net.Socket;
import java.io.IOException;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hdfs.DFSClient;
import org.apache.hadoop.hdfs.DFSInputStream;
import org.apache.hadoop.hdfs.SocketCache;
import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
import org.apache.hadoop.hdfs.protocol.LocatedBlock;
import org.apache.hadoop.hdfs.security.token.block.BlockTokenIdentifier;
import org.apache.hadoop.hdfs.server.datanode.DataNode;
import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
import org.apache.hadoop.security.token.Token;
import org.junit.Test;
import org.junit.AfterClass;
import org.junit.BeforeClass;
import static org.junit.Assert.*;
import org.mockito.Matchers;
import org.mockito.Mockito;
import org.mockito.stubbing.Answer;
import org.mockito.invocation.InvocationOnMock;
import static org.mockito.Mockito.spy;
/**
* This class tests the client connection caching in a single node
* mini-cluster.
*/
public class TestConnCache {
static final Log LOG = LogFactory.getLog(TestConnCache.class);
static final int BLOCK_SIZE = 4096;
static final int FILE_SIZE = 3 * BLOCK_SIZE;
static Configuration conf = null;
static MiniDFSCluster cluster = null;
static FileSystem fs = null;
static final Path testFile = new Path("/testConnCache.dat");
static byte authenticData[] = null;
static BlockReaderTestUtil util = null;
/**
* A mock Answer to remember the BlockReader used.
*
* It verifies that all invocation to DFSInputStream.getBlockReader()
* use the same socket.
*/
private class MockGetBlockReader implements Answer<RemoteBlockReader2> {
public RemoteBlockReader2 reader = null;
private Socket sock = null;
public RemoteBlockReader2 answer(InvocationOnMock invocation) throws Throwable {
RemoteBlockReader2 prevReader = reader;
reader = (RemoteBlockReader2) invocation.callRealMethod();
if (sock == null) {
sock = reader.dnSock;
} else if (prevReader != null) {
assertSame("DFSInputStream should use the same socket",
sock, reader.dnSock);
}
return reader;
}
}
@BeforeClass
public static void setupCluster() throws Exception {
final int REPLICATION_FACTOR = 1;
util = new BlockReaderTestUtil(REPLICATION_FACTOR);
cluster = util.getCluster();
conf = util.getConf();
fs = cluster.getFileSystem();
authenticData = util.writeFile(testFile, FILE_SIZE / 1024);
}
/**
* (Optionally) seek to position, read and verify data.
*
* Seek to specified position if pos is non-negative.
*/
private void pread(DFSInputStream in,
long pos,
byte[] buffer,
int offset,
int length)
throws IOException {
assertTrue("Test buffer too small", buffer.length >= offset + length);
if (pos >= 0)
in.seek(pos);
LOG.info("Reading from file of size " + in.getFileLength() +
" at offset " + in.getPos());
while (length > 0) {
int cnt = in.read(buffer, offset, length);
assertTrue("Error in read", cnt > 0);
offset += cnt;
length -= cnt;
}
// Verify
for (int i = 0; i < length; ++i) {
byte actual = buffer[i];
byte expect = authenticData[(int)pos + i];
assertEquals("Read data mismatch at file offset " + (pos + i) +
". Expects " + expect + "; got " + actual,
actual, expect);
}
}
/**
* Test the SocketCache itself.
*/
@Test
public void testSocketCache() throws IOException {
final int CACHE_SIZE = 4;
SocketCache cache = new SocketCache(CACHE_SIZE);
// Make a client
InetSocketAddress nnAddr =
new InetSocketAddress("localhost", cluster.getNameNodePort());
DFSClient client = new DFSClient(nnAddr, conf);
// Find out the DN addr
LocatedBlock block =
client.getNamenode().getBlockLocations(
testFile.toString(), 0, FILE_SIZE)
.getLocatedBlocks().get(0);
DataNode dn = util.getDataNode(block);
InetSocketAddress dnAddr = dn.getSelfAddr();
// Make some sockets to the DN
Socket[] dnSockets = new Socket[CACHE_SIZE];
for (int i = 0; i < dnSockets.length; ++i) {
dnSockets[i] = client.socketFactory.createSocket(
dnAddr.getAddress(), dnAddr.getPort());
}
// Insert a socket to the NN
Socket nnSock = new Socket(nnAddr.getAddress(), nnAddr.getPort());
cache.put(nnSock);
assertSame("Read the write", nnSock, cache.get(nnAddr));
cache.put(nnSock);
// Insert DN socks
for (Socket dnSock : dnSockets) {
cache.put(dnSock);
}
assertEquals("NN socket evicted", null, cache.get(nnAddr));
assertTrue("Evicted socket closed", nnSock.isClosed());
// Lookup the DN socks
for (Socket dnSock : dnSockets) {
assertEquals("Retrieve cached sockets", dnSock, cache.get(dnAddr));
dnSock.close();
}
assertEquals("Cache is empty", 0, cache.size());
}
/**
* Read a file served entirely from one DN. Seek around and read from
* different offsets. And verify that they all use the same socket.
*
* @throws java.io.IOException
*/
@Test
@SuppressWarnings("unchecked")
public void testReadFromOneDN() throws IOException {
LOG.info("Starting testReadFromOneDN()");
DFSClient client = new DFSClient(
new InetSocketAddress("localhost", cluster.getNameNodePort()), conf);
DFSInputStream in = spy(client.open(testFile.toString()));
LOG.info("opened " + testFile.toString());
byte[] dataBuf = new byte[BLOCK_SIZE];
MockGetBlockReader answer = new MockGetBlockReader();
Mockito.doAnswer(answer).when(in).getBlockReader(
(InetSocketAddress) Matchers.anyObject(),
(DatanodeInfo) Matchers.anyObject(),
Matchers.anyString(),
(ExtendedBlock) Matchers.anyObject(),
(Token<BlockTokenIdentifier>) Matchers.anyObject(),
Matchers.anyLong(),
Matchers.anyLong(),
Matchers.anyInt(),
Matchers.anyBoolean(),
Matchers.anyString());
// Initial read
pread(in, 0, dataBuf, 0, dataBuf.length);
// Read again and verify that the socket is the same
pread(in, FILE_SIZE - dataBuf.length, dataBuf, 0, dataBuf.length);
pread(in, 1024, dataBuf, 0, dataBuf.length);
pread(in, -1, dataBuf, 0, dataBuf.length); // No seek; just read
pread(in, 64, dataBuf, 0, dataBuf.length / 2);
in.close();
}
@AfterClass
public static void teardownCluster() throws Exception {
util.shutdown();
}
}