From 54221aa26ac98a240dc8c5821140e440c2b124ed Mon Sep 17 00:00:00 2001 From: Suresh Srinivas Date: Tue, 8 Jan 2013 16:59:29 +0000 Subject: [PATCH] HADOOP-9119. Add test to FileSystemContractBaseTest to verify integrity of overwritten files. Contributed by Steve Loughran. git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1430387 13f79535-47bb-0310-9956-ffa450edef68 --- .../hadoop-common/CHANGES.txt | 3 + .../hadoop/fs/FileSystemContractBaseTest.java | 197 ++++++++++++++---- 2 files changed, 161 insertions(+), 39 deletions(-) diff --git a/hadoop-common-project/hadoop-common/CHANGES.txt b/hadoop-common-project/hadoop-common/CHANGES.txt index e08e597a5ec..e10bab69c3b 100644 --- a/hadoop-common-project/hadoop-common/CHANGES.txt +++ b/hadoop-common-project/hadoop-common/CHANGES.txt @@ -423,6 +423,9 @@ Release 2.0.3-alpha - Unreleased HADOOP-9173. Add security token protobuf definition to common and use it in hdfs. (suresh) + HADOOP-9119. Add test to FileSystemContractBaseTest to verify integrity + of overwritten files. (Steve Loughran via suresh) + OPTIMIZATIONS HADOOP-8866. SampleQuantiles#query is O(N^2) instead of O(N). (Andrew Wang diff --git a/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/fs/FileSystemContractBaseTest.java b/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/fs/FileSystemContractBaseTest.java index 523feabee89..ea309a768a8 100644 --- a/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/fs/FileSystemContractBaseTest.java +++ b/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/fs/FileSystemContractBaseTest.java @@ -23,12 +23,9 @@ import java.io.IOException; import junit.framework.TestCase; +import org.apache.commons.logging.Log; +import org.apache.commons.logging.LogFactory; import org.apache.hadoop.conf.Configuration; -import org.apache.hadoop.fs.FSDataInputStream; -import org.apache.hadoop.fs.FSDataOutputStream; -import org.apache.hadoop.fs.FileStatus; -import org.apache.hadoop.fs.FileSystem; -import org.apache.hadoop.fs.Path; import org.apache.hadoop.fs.permission.FsPermission; /** @@ -45,15 +42,13 @@ import org.apache.hadoop.fs.permission.FsPermission; *

*/ public abstract class FileSystemContractBaseTest extends TestCase { + private static final Log LOG = + LogFactory.getLog(FileSystemContractBaseTest.class); + protected final static String TEST_UMASK = "062"; protected FileSystem fs; - protected byte[] data = new byte[getBlockSize() * 2]; // two blocks of data - { - for (int i = 0; i < data.length; i++) { - data[i] = (byte) (i % 10); - } - } - + protected byte[] data = dataset(getBlockSize() * 2, 0, 255); + @Override protected void tearDown() throws Exception { fs.delete(path("/test"), true); @@ -235,35 +230,16 @@ public abstract class FileSystemContractBaseTest extends TestCase { public void testWriteReadAndDeleteTwoBlocks() throws Exception { writeReadAndDelete(getBlockSize() * 2); } - + + /** + * Write a dataset, read it back in and verify that they match. + * Afterwards, the file is deleted. + * @param len length of data + * @throws IOException on IO failures + */ protected void writeReadAndDelete(int len) throws IOException { Path path = path("/test/hadoop/file"); - - fs.mkdirs(path.getParent()); - - FSDataOutputStream out = fs.create(path, false, - fs.getConf().getInt("io.file.buffer.size", 4096), - (short) 1, getBlockSize()); - out.write(data, 0, len); - out.close(); - - assertTrue("Exists", fs.exists(path)); - assertEquals("Length", len, fs.getFileStatus(path).getLen()); - - FSDataInputStream in = fs.open(path); - byte[] buf = new byte[len]; - in.readFully(0, buf); - in.close(); - - assertEquals(len, buf.length); - for (int i = 0; i < buf.length; i++) { - assertEquals("Position " + i, data[i], buf[i]); - } - - assertTrue("Deleted", fs.delete(path, false)); - - assertFalse("No longer exists", fs.exists(path)); - + writeAndRead(path, data, len, false, true); } public void testOverwrite() throws IOException { @@ -494,4 +470,147 @@ public abstract class FileSystemContractBaseTest extends TestCase { assertEquals("Source exists", srcExists, fs.exists(src)); assertEquals("Destination exists", dstExists, fs.exists(dst)); } + + /** + * Verify that if you take an existing file and overwrite it, the new values + * get picked up. + * This is a test for the behavior of eventually consistent + * filesystems. + * + * @throws Exception on any failure + */ + + public void testOverWriteAndRead() throws Exception { + int blockSize = getBlockSize(); + + byte[] filedata1 = dataset(blockSize * 2, 'A', 26); + byte[] filedata2 = dataset(blockSize * 2, 'a', 26); + Path path = path("/test/hadoop/file-overwrite"); + writeAndRead(path, filedata1, blockSize, true, false); + writeAndRead(path, filedata2, blockSize, true, false); + writeAndRead(path, filedata1, blockSize * 2, true, false); + writeAndRead(path, filedata2, blockSize * 2, true, false); + writeAndRead(path, filedata1, blockSize, true, false); + writeAndRead(path, filedata2, blockSize * 2, true, false); + } + + /** + * + * Write a file and read it in, validating the result. Optional flags control + * whether file overwrite operations should be enabled, and whether the + * file should be deleted afterwards. + * + * If there is a mismatch between what was written and what was expected, + * a small range of bytes either side of the first error are logged to aid + * diagnosing what problem occurred -whether it was a previous file + * or a corrupting of the current file. This assumes that two + * sequential runs to the same path use datasets with different character + * moduli. + * + * @param path path to write to + * @param len length of data + * @param overwrite should the create option allow overwrites? + * @param delete should the file be deleted afterwards? -with a verification + * that it worked. Deletion is not attempted if an assertion has failed + * earlier -it is not in a finally{} block. + * @throws IOException IO problems + */ + protected void writeAndRead(Path path, byte[] src, int len, + boolean overwrite, + boolean delete) throws IOException { + assertTrue("Not enough data in source array to write " + len + " bytes", + src.length >= len); + fs.mkdirs(path.getParent()); + + FSDataOutputStream out = fs.create(path, overwrite, + fs.getConf().getInt("io.file.buffer.size", + 4096), + (short) 1, getBlockSize()); + out.write(src, 0, len); + out.close(); + + assertTrue("Exists", fs.exists(path)); + assertEquals("Length", len, fs.getFileStatus(path).getLen()); + + FSDataInputStream in = fs.open(path); + byte[] buf = new byte[len]; + in.readFully(0, buf); + in.close(); + + assertEquals(len, buf.length); + int errors = 0; + int first_error_byte = -1; + for (int i = 0; i < len; i++) { + if (src[i] != buf[i]) { + if (errors == 0) { + first_error_byte = i; + } + errors++; + } + } + + if (errors > 0) { + String message = String.format(" %d errors in file of length %d", + errors, len); + LOG.warn(message); + // the range either side of the first error to print + // this is a purely arbitrary number, to aid user debugging + final int overlap = 10; + for (int i = Math.max(0, first_error_byte - overlap); + i < Math.min(first_error_byte + overlap, len); + i++) { + byte actual = buf[i]; + byte expected = src[i]; + String letter = toChar(actual); + String line = String.format("[%04d] %2x %s\n", i, actual, letter); + if (expected != actual) { + line = String.format("[%04d] %2x %s -expected %2x %s\n", + i, + actual, + letter, + expected, + toChar(expected)); + } + LOG.warn(line); + } + fail(message); + } + + if (delete) { + boolean deleted = fs.delete(path, false); + assertTrue("Deleted", deleted); + assertFalse("No longer exists", fs.exists(path)); + } + } + + /** + * Convert a byte to a character for printing. If the + * byte value is < 32 -and hence unprintable- the byte is + * returned as a two digit hex value + * @param b byte + * @return the printable character string + */ + protected String toChar(byte b) { + if (b >= 0x20) { + return Character.toString((char) b); + } else { + return String.format("%02x", b); + } + } + + /** + * Create a dataset for use in the tests; all data is in the range + * base to (base+modulo-1) inclusive + * @param len length of data + * @param base base of the data + * @param modulo the modulo + * @return the newly generated dataset + */ + protected byte[] dataset(int len, int base, int modulo) { + byte[] dataset = new byte[len]; + for (int i = 0; i < len; i++) { + dataset[i] = (byte) (base + (i % modulo)); + } + return dataset; + } }