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author | Xusen Yin <yinxusen@gmail.com> | 2014-04-04 11:12:47 -0700 |
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committer | Matei Zaharia <matei@databricks.com> | 2014-04-04 11:12:47 -0700 |
commit | f1fa617023d30d8cdc5acef0274bad8cc3e89cea (patch) | |
tree | 5eaf3f485c66a74ea260afbc3a0b941ad1621579 | |
parent | 01cf4c402b9fda59680e56112bfaa2b748416d0e (diff) | |
download | spark-f1fa617023d30d8cdc5acef0274bad8cc3e89cea.tar.gz spark-f1fa617023d30d8cdc5acef0274bad8cc3e89cea.tar.bz2 spark-f1fa617023d30d8cdc5acef0274bad8cc3e89cea.zip |
[SPARK-1133] Add whole text files reader in MLlib
Here is a pointer to the former [PR164](https://github.com/apache/spark/pull/164).
I add the pull request for the JIRA issue [SPARK-1133](https://spark-project.atlassian.net/browse/SPARK-1133), which brings a new files reader API in MLlib.
Author: Xusen Yin <yinxusen@gmail.com>
Closes #252 from yinxusen/whole-files-input and squashes the following commits:
7191be6 [Xusen Yin] refine comments
0af3faf [Xusen Yin] add JavaAPI test
01745ee [Xusen Yin] fix deletion error
cc97dca [Xusen Yin] move whole text file API to Spark core
d792cee [Xusen Yin] remove the typo character "+"
6bdf2c2 [Xusen Yin] test for small local file system block size
a1f1e7e [Xusen Yin] add two extra spaces
28cb0fe [Xusen Yin] add whole text files reader
6 files changed, 313 insertions, 3 deletions
diff --git a/core/src/main/scala/org/apache/spark/SparkContext.scala b/core/src/main/scala/org/apache/spark/SparkContext.scala index b23accbbb9..28a865c0ad 100644 --- a/core/src/main/scala/org/apache/spark/SparkContext.scala +++ b/core/src/main/scala/org/apache/spark/SparkContext.scala @@ -37,6 +37,7 @@ import org.apache.mesos.MesosNativeLibrary import org.apache.spark.broadcast.Broadcast import org.apache.spark.deploy.{LocalSparkCluster, SparkHadoopUtil} +import org.apache.spark.input.WholeTextFileInputFormat import org.apache.spark.partial.{ApproximateEvaluator, PartialResult} import org.apache.spark.rdd._ import org.apache.spark.scheduler._ @@ -372,6 +373,39 @@ class SparkContext( } /** + * Read a directory of text files from HDFS, a local file system (available on all nodes), or any + * Hadoop-supported file system URI. Each file is read as a single record and returned in a + * key-value pair, where the key is the path of each file, the value is the content of each file. + * + * <p> For example, if you have the following files: + * {{{ + * hdfs://a-hdfs-path/part-00000 + * hdfs://a-hdfs-path/part-00001 + * ... + * hdfs://a-hdfs-path/part-nnnnn + * }}} + * + * Do `val rdd = sparkContext.wholeTextFile("hdfs://a-hdfs-path")`, + * + * <p> then `rdd` contains + * {{{ + * (a-hdfs-path/part-00000, its content) + * (a-hdfs-path/part-00001, its content) + * ... + * (a-hdfs-path/part-nnnnn, its content) + * }}} + * + * @note Small files are perferred, large file is also allowable, but may cause bad performance. + */ + def wholeTextFiles(path: String): RDD[(String, String)] = { + newAPIHadoopFile( + path, + classOf[WholeTextFileInputFormat], + classOf[String], + classOf[String]) + } + + /** * Get an RDD for a Hadoop-readable dataset from a Hadoop JobConf given its InputFormat and other * necessary info (e.g. file name for a filesystem-based dataset, table name for HyperTable), * using the older MapReduce API (`org.apache.hadoop.mapred`). diff --git a/core/src/main/scala/org/apache/spark/api/java/JavaSparkContext.scala b/core/src/main/scala/org/apache/spark/api/java/JavaSparkContext.scala index e531a57ace..6cbdeac58d 100644 --- a/core/src/main/scala/org/apache/spark/api/java/JavaSparkContext.scala +++ b/core/src/main/scala/org/apache/spark/api/java/JavaSparkContext.scala @@ -154,6 +154,34 @@ class JavaSparkContext(val sc: SparkContext) extends JavaSparkContextVarargsWork */ def textFile(path: String, minSplits: Int): JavaRDD[String] = sc.textFile(path, minSplits) + /** + * Read a directory of text files from HDFS, a local file system (available on all nodes), or any + * Hadoop-supported file system URI. Each file is read as a single record and returned in a + * key-value pair, where the key is the path of each file, the value is the content of each file. + * + * <p> For example, if you have the following files: + * {{{ + * hdfs://a-hdfs-path/part-00000 + * hdfs://a-hdfs-path/part-00001 + * ... + * hdfs://a-hdfs-path/part-nnnnn + * }}} + * + * Do `JavaPairRDD<String, String> rdd = sparkContext.wholeTextFiles("hdfs://a-hdfs-path")`, + * + * <p> then `rdd` contains + * {{{ + * (a-hdfs-path/part-00000, its content) + * (a-hdfs-path/part-00001, its content) + * ... + * (a-hdfs-path/part-nnnnn, its content) + * }}} + * + * @note Small files are perferred, large file is also allowable, but may cause bad performance. + */ + def wholeTextFiles(path: String): JavaPairRDD[String, String] = + new JavaPairRDD(sc.wholeTextFiles(path)) + /** Get an RDD for a Hadoop SequenceFile with given key and value types. * * '''Note:''' Because Hadoop's RecordReader class re-uses the same Writable object for each diff --git a/core/src/main/scala/org/apache/spark/input/WholeTextFileInputFormat.scala b/core/src/main/scala/org/apache/spark/input/WholeTextFileInputFormat.scala new file mode 100644 index 0000000000..4887fb6b84 --- /dev/null +++ b/core/src/main/scala/org/apache/spark/input/WholeTextFileInputFormat.scala @@ -0,0 +1,47 @@ +/* + * 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.spark.input + +import org.apache.hadoop.fs.Path +import org.apache.hadoop.mapreduce.InputSplit +import org.apache.hadoop.mapreduce.JobContext +import org.apache.hadoop.mapreduce.lib.input.CombineFileInputFormat +import org.apache.hadoop.mapreduce.RecordReader +import org.apache.hadoop.mapreduce.TaskAttemptContext +import org.apache.hadoop.mapreduce.lib.input.CombineFileRecordReader +import org.apache.hadoop.mapreduce.lib.input.CombineFileSplit + +/** + * A [[org.apache.hadoop.mapreduce.lib.input.CombineFileInputFormat CombineFileInputFormat]] for + * reading whole text files. Each file is read as key-value pair, where the key is the file path and + * the value is the entire content of file. + */ + +private[spark] class WholeTextFileInputFormat extends CombineFileInputFormat[String, String] { + override protected def isSplitable(context: JobContext, file: Path): Boolean = false + + override def createRecordReader( + split: InputSplit, + context: TaskAttemptContext): RecordReader[String, String] = { + + new CombineFileRecordReader[String, String]( + split.asInstanceOf[CombineFileSplit], + context, + classOf[WholeTextFileRecordReader]) + } +} diff --git a/core/src/main/scala/org/apache/spark/input/WholeTextFileRecordReader.scala b/core/src/main/scala/org/apache/spark/input/WholeTextFileRecordReader.scala new file mode 100644 index 0000000000..c3dabd2e79 --- /dev/null +++ b/core/src/main/scala/org/apache/spark/input/WholeTextFileRecordReader.scala @@ -0,0 +1,72 @@ +/* + * 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.spark.input + +import com.google.common.io.{ByteStreams, Closeables} + +import org.apache.hadoop.io.Text +import org.apache.hadoop.mapreduce.InputSplit +import org.apache.hadoop.mapreduce.lib.input.CombineFileSplit +import org.apache.hadoop.mapreduce.RecordReader +import org.apache.hadoop.mapreduce.TaskAttemptContext + +/** + * A [[org.apache.hadoop.mapreduce.RecordReader RecordReader]] for reading a single whole text file + * out in a key-value pair, where the key is the file path and the value is the entire content of + * the file. + */ +private[spark] class WholeTextFileRecordReader( + split: CombineFileSplit, + context: TaskAttemptContext, + index: Integer) + extends RecordReader[String, String] { + + private val path = split.getPath(index) + private val fs = path.getFileSystem(context.getConfiguration) + + // True means the current file has been processed, then skip it. + private var processed = false + + private val key = path.toString + private var value: String = null + + override def initialize(split: InputSplit, context: TaskAttemptContext) = {} + + override def close() = {} + + override def getProgress = if (processed) 1.0f else 0.0f + + override def getCurrentKey = key + + override def getCurrentValue = value + + override def nextKeyValue = { + if (!processed) { + val fileIn = fs.open(path) + val innerBuffer = ByteStreams.toByteArray(fileIn) + + value = new Text(innerBuffer).toString + Closeables.close(fileIn, false) + + processed = true + true + } else { + false + } + } +} diff --git a/core/src/test/java/org/apache/spark/JavaAPISuite.java b/core/src/test/java/org/apache/spark/JavaAPISuite.java index c6b65c7348..2372f2d992 100644 --- a/core/src/test/java/org/apache/spark/JavaAPISuite.java +++ b/core/src/test/java/org/apache/spark/JavaAPISuite.java @@ -17,9 +17,7 @@ package org.apache.spark; -import java.io.File; -import java.io.IOException; -import java.io.Serializable; +import java.io.*; import java.util.*; import scala.Tuple2; @@ -600,6 +598,32 @@ public class JavaAPISuite implements Serializable { } @Test + public void wholeTextFiles() throws IOException { + byte[] content1 = "spark is easy to use.\n".getBytes(); + byte[] content2 = "spark is also easy to use.\n".getBytes(); + + File tempDir = Files.createTempDir(); + String tempDirName = tempDir.getAbsolutePath(); + DataOutputStream ds = new DataOutputStream(new FileOutputStream(tempDirName + "/part-00000")); + ds.write(content1); + ds.close(); + ds = new DataOutputStream(new FileOutputStream(tempDirName + "/part-00001")); + ds.write(content2); + ds.close(); + + HashMap<String, String> container = new HashMap<String, String>(); + container.put(tempDirName+"/part-00000", new Text(content1).toString()); + container.put(tempDirName+"/part-00001", new Text(content2).toString()); + + JavaPairRDD<String, String> readRDD = sc.wholeTextFiles(tempDirName); + List<Tuple2<String, String>> result = readRDD.collect(); + + for (Tuple2<String, String> res : result) { + Assert.assertEquals(res._2(), container.get(res._1())); + } + } + + @Test public void textFilesCompressed() throws IOException { File tempDir = Files.createTempDir(); String outputDir = new File(tempDir, "output").getAbsolutePath(); diff --git a/core/src/test/scala/org/apache/spark/input/WholeTextFileRecordReaderSuite.scala b/core/src/test/scala/org/apache/spark/input/WholeTextFileRecordReaderSuite.scala new file mode 100644 index 0000000000..09e35bfc8f --- /dev/null +++ b/core/src/test/scala/org/apache/spark/input/WholeTextFileRecordReaderSuite.scala @@ -0,0 +1,105 @@ +/* + * 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.spark.input + +import java.io.DataOutputStream +import java.io.File +import java.io.FileOutputStream + +import scala.collection.immutable.IndexedSeq + +import com.google.common.io.Files + +import org.scalatest.BeforeAndAfterAll +import org.scalatest.FunSuite + +import org.apache.hadoop.io.Text + +import org.apache.spark.SparkContext + +/** + * Tests the correctness of + * [[org.apache.spark.input.WholeTextFileRecordReader WholeTextFileRecordReader]]. A temporary + * directory is created as fake input. Temporal storage would be deleted in the end. + */ +class WholeTextFileRecordReaderSuite extends FunSuite with BeforeAndAfterAll { + private var sc: SparkContext = _ + + override def beforeAll() { + sc = new SparkContext("local", "test") + + // Set the block size of local file system to test whether files are split right or not. + sc.hadoopConfiguration.setLong("fs.local.block.size", 32) + } + + override def afterAll() { + sc.stop() + } + + private def createNativeFile(inputDir: File, fileName: String, contents: Array[Byte]) = { + val out = new DataOutputStream(new FileOutputStream(s"${inputDir.toString}/$fileName")) + out.write(contents, 0, contents.length) + out.close() + } + + /** + * This code will test the behaviors of WholeTextFileRecordReader based on local disk. There are + * three aspects to check: + * 1) Whether all files are read; + * 2) Whether paths are read correctly; + * 3) Does the contents be the same. + */ + test("Correctness of WholeTextFileRecordReader.") { + + val dir = Files.createTempDir() + println(s"Local disk address is ${dir.toString}.") + + WholeTextFileRecordReaderSuite.files.foreach { case (filename, contents) => + createNativeFile(dir, filename, contents) + } + + val res = sc.wholeTextFiles(dir.toString).collect() + + assert(res.size === WholeTextFileRecordReaderSuite.fileNames.size, + "Number of files read out does not fit with the actual value.") + + for ((filename, contents) <- res) { + val shortName = filename.split('/').last + assert(WholeTextFileRecordReaderSuite.fileNames.contains(shortName), + s"Missing file name $filename.") + assert(contents === new Text(WholeTextFileRecordReaderSuite.files(shortName)).toString, + s"file $filename contents can not match.") + } + + dir.delete() + } +} + +/** + * Files to be tested are defined here. + */ +object WholeTextFileRecordReaderSuite { + private val testWords: IndexedSeq[Byte] = "Spark is easy to use.\n".map(_.toByte) + + private val fileNames = Array("part-00000", "part-00001", "part-00002") + private val fileLengths = Array(10, 100, 1000) + + private val files = fileLengths.zip(fileNames).map { case (upperBound, filename) => + filename -> Stream.continually(testWords.toList.toStream).flatten.take(upperBound).toArray + }.toMap +} |