TestSnapshotFileLength.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.
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package org.apache.hadoop.hdfs.server.namenode.snapshot;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.PrintStream;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.FileChecksum;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.hdfs.AppendTestUtil;
import org.apache.hadoop.hdfs.DFSConfigKeys;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import static org.hamcrest.CoreMatchers.is;
import static org.hamcrest.CoreMatchers.not;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertThat;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.fail;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FsShell;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hdfs.DFSTestUtil;
import org.apache.hadoop.hdfs.DistributedFileSystem;
import org.apache.hadoop.hdfs.MiniDFSCluster;
import org.apache.hadoop.util.ToolRunner;
public class TestSnapshotFileLength {
private static final long SEED = 0;
private static final short REPLICATION = 1;
private static final int BLOCKSIZE = 1024;
private static final Configuration conf = new Configuration();
private static MiniDFSCluster cluster;
private static DistributedFileSystem hdfs;
private final Path dir = new Path("/TestSnapshotFileLength");
private final Path sub = new Path(dir, "sub1");
private final String file1Name = "file1";
private final String snapshot1 = "snapshot1";
@Before
public void setUp() throws Exception {
conf.setLong(DFSConfigKeys.DFS_NAMENODE_MIN_BLOCK_SIZE_KEY, BLOCKSIZE);
conf.setInt(DFSConfigKeys.DFS_BYTES_PER_CHECKSUM_KEY, BLOCKSIZE);
cluster = new MiniDFSCluster.Builder(conf).numDataNodes(REPLICATION)
.build();
cluster.waitActive();
hdfs = cluster.getFileSystem();
}
@After
public void tearDown() throws Exception {
if (cluster != null) {
cluster.shutdown();
cluster = null;
}
}
/**
* Test that we cannot read a file beyond its snapshot length
* when accessing it via a snapshot path.
*
*/
@Test (timeout=300000)
public void testSnapshotfileLength() throws Exception {
hdfs.mkdirs(sub);
int bytesRead;
byte[] buffer = new byte[BLOCKSIZE * 8];
int origLen = BLOCKSIZE + 1;
int toAppend = BLOCKSIZE;
FSDataInputStream fis = null;
FileStatus fileStatus = null;
// Create and write a file.
Path file1 = new Path(sub, file1Name);
DFSTestUtil.createFile(hdfs, file1, BLOCKSIZE, 0, BLOCKSIZE, REPLICATION, SEED);
DFSTestUtil.appendFile(hdfs, file1, origLen);
// Create a snapshot on the parent directory.
hdfs.allowSnapshot(sub);
hdfs.createSnapshot(sub, snapshot1);
Path file1snap1
= SnapshotTestHelper.getSnapshotPath(sub, snapshot1, file1Name);
final FileChecksum snapChksum1 = hdfs.getFileChecksum(file1snap1);
assertThat("file and snapshot file checksums are not equal",
hdfs.getFileChecksum(file1), is(snapChksum1));
// Append to the file.
FSDataOutputStream out = hdfs.append(file1);
// Nothing has been appended yet. All checksums should still be equal.
// HDFS-8150:Fetching checksum for file under construction should fail
try {
hdfs.getFileChecksum(file1);
fail("getFileChecksum should fail for files "
+ "with blocks under construction");
} catch (IOException ie) {
assertTrue(ie.getMessage().contains(
"Fail to get checksum, since file " + file1
+ " is under construction."));
}
assertThat("snapshot checksum (post-open for append) has changed",
hdfs.getFileChecksum(file1snap1), is(snapChksum1));
try {
AppendTestUtil.write(out, 0, toAppend);
out.hflush();
// Test reading from snapshot of file that is open for append
byte[] dataFromSnapshot = DFSTestUtil.readFileBuffer(hdfs, file1snap1);
assertThat("Wrong data size in snapshot.",
dataFromSnapshot.length, is(origLen));
// Verify that checksum didn't change
assertThat("snapshot checksum (post-append) has changed",
hdfs.getFileChecksum(file1snap1), is(snapChksum1));
} finally {
out.close();
}
assertThat("file and snapshot file checksums (post-close) are equal",
hdfs.getFileChecksum(file1), not(snapChksum1));
assertThat("snapshot file checksum (post-close) has changed",
hdfs.getFileChecksum(file1snap1), is(snapChksum1));
// Make sure we can read the entire file via its non-snapshot path.
fileStatus = hdfs.getFileStatus(file1);
assertThat(fileStatus.getLen(), is((long) origLen + toAppend));
fis = hdfs.open(file1);
bytesRead = fis.read(0, buffer, 0, buffer.length);
assertThat(bytesRead, is(origLen + toAppend));
fis.close();
// Try to open the file via its snapshot path.
fis = hdfs.open(file1snap1);
fileStatus = hdfs.getFileStatus(file1snap1);
assertThat(fileStatus.getLen(), is((long) origLen));
// Make sure we can only read up to the snapshot length.
bytesRead = fis.read(0, buffer, 0, buffer.length);
assertThat(bytesRead, is(origLen));
fis.close();
byte[] dataFromSnapshot = DFSTestUtil.readFileBuffer(hdfs,
file1snap1);
assertThat("Wrong data size in snapshot.",
dataFromSnapshot.length, is(origLen));
}
/**
* Adding as part of jira HDFS-5343
* Test for checking the cat command on snapshot path it
* cannot read a file beyond snapshot file length
* @throws Exception
*/
@Test (timeout = 600000)
public void testSnapshotFileLengthWithCatCommand() throws Exception {
FSDataInputStream fis = null;
FileStatus fileStatus = null;
int bytesRead;
byte[] buffer = new byte[BLOCKSIZE * 8];
hdfs.mkdirs(sub);
Path file1 = new Path(sub, file1Name);
DFSTestUtil.createFile(hdfs, file1, BLOCKSIZE, REPLICATION, SEED);
hdfs.allowSnapshot(sub);
hdfs.createSnapshot(sub, snapshot1);
DFSTestUtil.appendFile(hdfs, file1, BLOCKSIZE);
// Make sure we can read the entire file via its non-snapshot path.
fileStatus = hdfs.getFileStatus(file1);
assertEquals("Unexpected file length", BLOCKSIZE * 2, fileStatus.getLen());
fis = hdfs.open(file1);
bytesRead = fis.read(buffer, 0, buffer.length);
assertEquals("Unexpected # bytes read", BLOCKSIZE * 2, bytesRead);
fis.close();
Path file1snap1 =
SnapshotTestHelper.getSnapshotPath(sub, snapshot1, file1Name);
fis = hdfs.open(file1snap1);
fileStatus = hdfs.getFileStatus(file1snap1);
assertEquals(fileStatus.getLen(), BLOCKSIZE);
// Make sure we can only read up to the snapshot length.
bytesRead = fis.read(buffer, 0, buffer.length);
assertEquals("Unexpected # bytes read", BLOCKSIZE, bytesRead);
fis.close();
PrintStream outBackup = System.out;
PrintStream errBackup = System.err;
ByteArrayOutputStream bao = new ByteArrayOutputStream();
System.setOut(new PrintStream(bao));
System.setErr(new PrintStream(bao));
// Make sure we can cat the file upto to snapshot length
FsShell shell = new FsShell();
try {
ToolRunner.run(conf, shell, new String[] { "-cat",
"/TestSnapshotFileLength/sub1/.snapshot/snapshot1/file1" });
assertEquals("Unexpected # bytes from -cat", BLOCKSIZE, bao.size());
} finally {
System.setOut(outBackup);
System.setErr(errBackup);
}
}
}