diff options
19 files changed, 233 insertions, 168 deletions
diff --git a/core/src/main/scala/spark/RDD.scala b/core/src/main/scala/spark/RDD.scala index 59e50a0b6b..1574533430 100644 --- a/core/src/main/scala/spark/RDD.scala +++ b/core/src/main/scala/spark/RDD.scala @@ -101,7 +101,6 @@ abstract class RDD[T: ClassManifest]( val partitioner: Option[Partitioner] = None - // ======================================================================= // Methods and fields available on all RDDs // ======================================================================= diff --git a/docs/_plugins/copy_api_dirs.rb b/docs/_plugins/copy_api_dirs.rb index e61c105449..7654511eeb 100644 --- a/docs/_plugins/copy_api_dirs.rb +++ b/docs/_plugins/copy_api_dirs.rb @@ -2,7 +2,7 @@ require 'fileutils' include FileUtils if ENV['SKIP_SCALADOC'] != '1' - projects = ["core", "examples", "repl", "bagel"] + projects = ["core", "examples", "repl", "bagel", "streaming"] puts "Moving to project root and building scaladoc." curr_dir = pwd @@ -11,7 +11,7 @@ if ENV['SKIP_SCALADOC'] != '1' puts "Running sbt/sbt doc from " + pwd + "; this may take a few minutes..." puts `sbt/sbt doc` - puts "moving back into docs dir." + puts "Moving back into docs dir." cd("docs") # Copy over the scaladoc from each project into the docs directory. diff --git a/docs/streaming-programming-guide.md b/docs/streaming-programming-guide.md index 90916545bc..7c421ac70f 100644 --- a/docs/streaming-programming-guide.md +++ b/docs/streaming-programming-guide.md @@ -2,33 +2,44 @@ layout: global title: Streaming (Alpha) Programming Guide --- + +{:toc} + +# Overview +A Spark Streaming application is very similar to a Spark application; it consists of a *driver program* that runs the user's `main` function and continuous executes various *parallel operations* on input streams of data. The main abstraction Spark Streaming provides is a *discretized stream* (DStream), which is a continuous sequence of RDDs (distributed collection of elements) representing a continuous stream of data. DStreams can created from live incoming data (such as data from a socket, Kafka, etc.) or it can be generated by transformation of existing DStreams using parallel operators like map, reduce, and window. The basic processing model is as follows: +(i) While a Spark Streaming driver program is running, the system receives data from various sources and and divides the data into batches. Each batch of data is treated as a RDD, that is a immutable and parallel collection of data. These input data RDDs are automatically persisted in memory (serialized by default) and replicated to two nodes for fault-tolerance. This sequence of RDDs is collectively referred to as an InputDStream. +(ii) Data received by InputDStreams are processed processed using DStream operations. Since all data is represented as RDDs and all DStream operations as RDD operations, data is automatically recovered in the event of node failures. + +This guide shows some how to start programming with DStreams. + # Initializing Spark Streaming The first thing a Spark Streaming program must do is create a `StreamingContext` object, which tells Spark how to access a cluster. A `StreamingContext` can be created from an existing `SparkContext`, or directly: {% highlight scala %} -new StreamingContext(master, jobName, [sparkHome], [jars]) -new StreamingContext(sparkContext) -{% endhighlight %} - -Once a context is instantiated, the batch interval must be set: +import spark.SparkContext +import SparkContext._ -{% highlight scala %} -context.setBatchDuration(Milliseconds(2000)) +new StreamingContext(master, frameworkName, batchDuration) +new StreamingContext(sparkContext, batchDuration) {% endhighlight %} +The `master` parameter is either the [Mesos master URL](running-on-mesos.html) (for running on a cluster)or the special "local" string (for local mode) that is used to create a Spark Context. For more information about this please refer to the [Spark programming guide](scala-programming-guide.html). -# DStreams - Discretized Streams -The primary abstraction in Spark Streaming is a DStream. A DStream represents distributed collection which is computed periodically according to a specified batch interval. DStream's can be chained together to create complex chains of transformation on streaming data. DStreams can be created by operating on existing DStreams or from an input source. To creating DStreams from an input source, use the StreamingContext: + +# Creating Input Sources - InputDStreams +The StreamingContext is used to creating InputDStreams from input sources: {% highlight scala %} -context.neworkStream(host, port) // A stream that reads from a socket -context.flumeStream(hosts, ports) // A stream populated by a Flume flow +context.neworkStream(host, port) // Creates a stream that uses a TCP socket to read data from <host>:<port> +context.flumeStream(host, port) // Creates a stream populated by a Flume flow {% endhighlight %} -# DStream Operators +A complete list of input sources is available in the [DStream API doc](api/streaming/index.html#spark.streaming.StreamingContext). + +## DStream Operations Once an input stream has been created, you can transform it using _stream operators_. Most of these operators return new DStreams which you can further transform. Eventually, you'll need to call an _output operator_, which forces evaluation of the stream by writing data out to an external source. -## Transformations +### Transformations DStreams support many of the transformations available on normal Spark RDD's: @@ -73,20 +84,13 @@ DStreams support many of the transformations available on normal Spark RDD's: <td> <b>cogroup</b>(<i>otherStream</i>, [<i>numTasks</i>]) </td> <td> When called on streams of type (K, V) and (K, W), returns a stream of (K, Seq[V], Seq[W]) tuples. This operation is also called <code>groupWith</code>. </td> </tr> -</table> - -DStreams also support the following additional transformations: - -<table class="table"> <tr> <td> <b>reduce</b>(<i>func</i>) </td> <td> Create a new single-element stream by aggregating the elements of the stream using a function func (which takes two arguments and returns one). The function should be associative so that it can be computed correctly in parallel. </td> </tr> </table> - -## Windowed Transformations -Spark streaming features windowed computations, which allow you to report statistics over a sliding window of data. All window functions take a <i>windowTime</i>, which represents the width of the window and a <i>slideTime</i>, which represents the frequency during which the window is calculated. +Spark Streaming features windowed computations, which allow you to report statistics over a sliding window of data. All window functions take a <i>windowTime</i>, which represents the width of the window and a <i>slideTime</i>, which represents the frequency during which the window is calculated. <table class="table"> <tr><th style="width:25%">Transformation</th><th>Meaning</th></tr> @@ -128,7 +132,7 @@ Spark streaming features windowed computations, which allow you to report statis </table> -## Output Operators +### Output Operators When an output operator is called, it triggers the computation of a stream. Currently the following output operators are defined: <table class="table"> @@ -140,22 +144,22 @@ When an output operator is called, it triggers the computation of a stream. Curr <tr> <td> <b>print</b>() </td> - <td> Prints the contents of this DStream on the driver. At each interval, this will take at most ten elements from the DStream's RDD and print them. </td> + <td> Prints first ten elements of every batch of data in a DStream on the driver. </td> </tr> <tr> - <td> <b>saveAsObjectFile</b>(<i>prefix</i>, [<i>suffix</i>]) </td> + <td> <b>saveAsObjectFiles</b>(<i>prefix</i>, [<i>suffix</i>]) </td> <td> Save this DStream's contents as a <code>SequenceFile</code> of serialized objects. The file name at each batch interval is calculated based on <i>prefix</i> and <i>suffix</i>: <i>"prefix-TIME_IN_MS[.suffix]"</i>. </td> </tr> <tr> - <td> <b>saveAsTextFile</b>(<i>prefix</i>, <i>suffix</i>) </td> + <td> <b>saveAsTextFiles</b>(<i>prefix</i>, [<i>suffix</i>]) </td> <td> Save this DStream's contents as a text files. The file name at each batch interval is calculated based on <i>prefix</i> and <i>suffix</i>: <i>"prefix-TIME_IN_MS[.suffix]"</i>. </td> </tr> <tr> - <td> <b>saveAsHadoopFiles</b>(<i>prefix</i>, <i>suffix</i>) </td> + <td> <b>saveAsHadoopFiles</b>(<i>prefix</i>, [<i>suffix</i>]) </td> <td> Save this DStream's contents as a Hadoop file. The file name at each batch interval is calculated based on <i>prefix</i> and <i>suffix</i>: <i>"prefix-TIME_IN_MS[.suffix]"</i>. </td> </tr> diff --git a/streaming/src/main/scala/spark/streaming/Checkpoint.scala b/streaming/src/main/scala/spark/streaming/Checkpoint.scala index 770f7b0cc0..11a7232d7b 100644 --- a/streaming/src/main/scala/spark/streaming/Checkpoint.scala +++ b/streaming/src/main/scala/spark/streaming/Checkpoint.scala @@ -8,6 +8,7 @@ import org.apache.hadoop.conf.Configuration import java.io._ +private[streaming] class Checkpoint(@transient ssc: StreamingContext, val checkpointTime: Time) extends Logging with Serializable { val master = ssc.sc.master @@ -30,6 +31,7 @@ class Checkpoint(@transient ssc: StreamingContext, val checkpointTime: Time) /** * Convenience class to speed up the writing of graph checkpoint to file */ +private[streaming] class CheckpointWriter(checkpointDir: String) extends Logging { val file = new Path(checkpointDir, "graph") val conf = new Configuration() @@ -65,7 +67,7 @@ class CheckpointWriter(checkpointDir: String) extends Logging { } - +private[streaming] object CheckpointReader extends Logging { def read(path: String): Checkpoint = { @@ -103,6 +105,7 @@ object CheckpointReader extends Logging { } } +private[streaming] class ObjectInputStreamWithLoader(inputStream_ : InputStream, loader: ClassLoader) extends ObjectInputStream(inputStream_) { override def resolveClass(desc: ObjectStreamClass): Class[_] = { try { diff --git a/streaming/src/main/scala/spark/streaming/DStream.scala b/streaming/src/main/scala/spark/streaming/DStream.scala index d5048aeed7..3834b57ed3 100644 --- a/streaming/src/main/scala/spark/streaming/DStream.scala +++ b/streaming/src/main/scala/spark/streaming/DStream.scala @@ -21,7 +21,7 @@ import org.apache.hadoop.conf.Configuration * A Discretized Stream (DStream), the basic abstraction in Spark Streaming, is a continuous * sequence of RDDs (of the same type) representing a continuous stream of data (see [[spark.RDD]] * for more details on RDDs). DStreams can either be created from live data (such as, data from - * HDFS. Kafka or Flume) or it can be generated by transformation existing DStreams using operations + * HDFS, Kafka or Flume) or it can be generated by transformation existing DStreams using operations * such as `map`, `window` and `reduceByKeyAndWindow`. While a Spark Streaming program is running, each * DStream periodically generates a RDD, either from live data or by transforming the RDD generated * by a parent DStream. @@ -38,33 +38,28 @@ import org.apache.hadoop.conf.Configuration * - A function that is used to generate an RDD after each time interval */ -case class DStreamCheckpointData(rdds: HashMap[Time, Any]) - -abstract class DStream[T: ClassManifest] (@transient var ssc: StreamingContext) -extends Serializable with Logging { +abstract class DStream[T: ClassManifest] ( + @transient protected[streaming] var ssc: StreamingContext + ) extends Serializable with Logging { initLogging() - /** - * ---------------------------------------------- - * Methods that must be implemented by subclasses - * ---------------------------------------------- - */ + // ======================================================================= + // Methods that should be implemented by subclasses of DStream + // ======================================================================= - // Time interval at which the DStream generates an RDD + /** Time interval after which the DStream generates a RDD */ def slideTime: Time - // List of parent DStreams on which this DStream depends on + /** List of parent DStreams on which this DStream depends on */ def dependencies: List[DStream[_]] - // Key method that computes RDD for a valid time + /** Method that generates a RDD for the given time */ def compute (validTime: Time): Option[RDD[T]] - /** - * --------------------------------------- - * Other general fields and methods of DStream - * --------------------------------------- - */ + // ======================================================================= + // Methods and fields available on all DStreams + // ======================================================================= // RDDs generated, marked as protected[streaming] so that testsuites can access it @transient @@ -87,12 +82,15 @@ extends Serializable with Logging { // Reference to whole DStream graph protected[streaming] var graph: DStreamGraph = null - def isInitialized = (zeroTime != null) + protected[streaming] def isInitialized = (zeroTime != null) // Duration for which the DStream requires its parent DStream to remember each RDD created - def parentRememberDuration = rememberDuration + protected[streaming] def parentRememberDuration = rememberDuration + + /** Returns the StreamingContext associated with this DStream */ + def context() = ssc - // Set caching level for the RDDs created by this DStream + /** Persists the RDDs of this DStream with the given storage level */ def persist(level: StorageLevel): DStream[T] = { if (this.isInitialized) { throw new UnsupportedOperationException( @@ -102,11 +100,16 @@ extends Serializable with Logging { this } + /** Persists RDDs of this DStream with the default storage level (MEMORY_ONLY_SER) */ def persist(): DStream[T] = persist(StorageLevel.MEMORY_ONLY_SER) - - // Turn on the default caching level for this RDD + + /** Persists RDDs of this DStream with the default storage level (MEMORY_ONLY_SER) */ def cache(): DStream[T] = persist() + /** + * Enable periodic checkpointing of RDDs of this DStream + * @param interval Time interval after which generated RDD will be checkpointed + */ def checkpoint(interval: Time): DStream[T] = { if (isInitialized) { throw new UnsupportedOperationException( @@ -285,7 +288,7 @@ extends Serializable with Logging { * Generates a SparkStreaming job for the given time. This is an internal method that * should not be called directly. This default implementation creates a job * that materializes the corresponding RDD. Subclasses of DStream may override this - * (eg. PerRDDForEachDStream). + * (eg. ForEachDStream). */ protected[streaming] def generateJob(time: Time): Option[Job] = { getOrCompute(time) match { @@ -420,65 +423,96 @@ extends Serializable with Logging { generatedRDDs = new HashMap[Time, RDD[T]] () } - /** - * -------------- - * DStream operations - * -------------- - */ + // ======================================================================= + // DStream operations + // ======================================================================= + + /** Returns a new DStream by applying a function to all elements of this DStream. */ def map[U: ClassManifest](mapFunc: T => U): DStream[U] = { new MappedDStream(this, ssc.sc.clean(mapFunc)) } + /** + * Returns a new DStream by applying a function to all elements of this DStream, + * and then flattening the results + */ def flatMap[U: ClassManifest](flatMapFunc: T => Traversable[U]): DStream[U] = { new FlatMappedDStream(this, ssc.sc.clean(flatMapFunc)) } + /** Returns a new DStream containing only the elements that satisfy a predicate. */ def filter(filterFunc: T => Boolean): DStream[T] = new FilteredDStream(this, filterFunc) + /** + * Return a new DStream in which each RDD is generated by applying glom() to each RDD of + * this DStream. Applying glom() to an RDD coalesces all elements within each partition into + * an array. + */ def glom(): DStream[Array[T]] = new GlommedDStream(this) - def mapPartitions[U: ClassManifest](mapPartFunc: Iterator[T] => Iterator[U]): DStream[U] = { - new MapPartitionedDStream(this, ssc.sc.clean(mapPartFunc)) + /** + * Return a new DStream in which each RDD is generated by applying mapPartitions() to each RDDs + * of this DStream. Applying mapPartitions() to an RDD applies a function to each partition + * of the RDD. + */ + def mapPartitions[U: ClassManifest]( + mapPartFunc: Iterator[T] => Iterator[U], + preservePartitioning: Boolean = false + ): DStream[U] = { + new MapPartitionedDStream(this, ssc.sc.clean(mapPartFunc), preservePartitioning) } - def reduce(reduceFunc: (T, T) => T): DStream[T] = this.map(x => (null, x)).reduceByKey(reduceFunc, 1).map(_._2) + /** + * Returns a new DStream in which each RDD has a single element generated by reducing each RDD + * of this DStream. + */ + def reduce(reduceFunc: (T, T) => T): DStream[T] = + this.map(x => (null, x)).reduceByKey(reduceFunc, 1).map(_._2) + /** + * Returns a new DStream in which each RDD has a single element generated by counting each RDD + * of this DStream. + */ def count(): DStream[Int] = this.map(_ => 1).reduce(_ + _) - - def collect(): DStream[Seq[T]] = this.map(x => (null, x)).groupByKey(1).map(_._2) - - def foreach(foreachFunc: T => Unit) { - val newStream = new PerElementForEachDStream(this, ssc.sc.clean(foreachFunc)) - ssc.registerOutputStream(newStream) - newStream - } - def foreachRDD(foreachFunc: RDD[T] => Unit) { - foreachRDD((r: RDD[T], t: Time) => foreachFunc(r)) + /** + * Applies a function to each RDD in this DStream. This is an output operator, so + * this DStream will be registered as an output stream and therefore materialized. + */ + def foreach(foreachFunc: RDD[T] => Unit) { + foreach((r: RDD[T], t: Time) => foreachFunc(r)) } - def foreachRDD(foreachFunc: (RDD[T], Time) => Unit) { - val newStream = new PerRDDForEachDStream(this, ssc.sc.clean(foreachFunc)) + /** + * Applies a function to each RDD in this DStream. This is an output operator, so + * this DStream will be registered as an output stream and therefore materialized. + */ + def foreach(foreachFunc: (RDD[T], Time) => Unit) { + val newStream = new ForEachDStream(this, ssc.sc.clean(foreachFunc)) ssc.registerOutputStream(newStream) newStream } - def transformRDD[U: ClassManifest](transformFunc: RDD[T] => RDD[U]): DStream[U] = { - transformRDD((r: RDD[T], t: Time) => transformFunc(r)) + /** + * Returns a new DStream in which each RDD is generated by applying a function + * on each RDD of this DStream. + */ + def transform[U: ClassManifest](transformFunc: RDD[T] => RDD[U]): DStream[U] = { + transform((r: RDD[T], t: Time) => transformFunc(r)) } - def transformRDD[U: ClassManifest](transformFunc: (RDD[T], Time) => RDD[U]): DStream[U] = { + /** + * Returns a new DStream in which each RDD is generated by applying a function + * on each RDD of this DStream. + */ + def transform[U: ClassManifest](transformFunc: (RDD[T], Time) => RDD[U]): DStream[U] = { new TransformedDStream(this, ssc.sc.clean(transformFunc)) } - def toBlockingQueue() = { - val queue = new ArrayBlockingQueue[RDD[T]](10000) - this.foreachRDD(rdd => { - queue.add(rdd) - }) - queue - } - + /** + * Prints the first ten elements of each RDD generated in this DStream. This is an output + * operator, so this DStream will be registered as an output stream and there materialized. + */ def print() { def foreachFunc = (rdd: RDD[T], time: Time) => { val first11 = rdd.take(11) @@ -489,18 +523,42 @@ extends Serializable with Logging { if (first11.size > 10) println("...") println() } - val newStream = new PerRDDForEachDStream(this, ssc.sc.clean(foreachFunc)) + val newStream = new ForEachDStream(this, ssc.sc.clean(foreachFunc)) ssc.registerOutputStream(newStream) } + /** + * Return a new DStream which is computed based on windowed batches of this DStream. + * The new DStream generates RDDs with the same interval as this DStream. + * @param windowTime width of the window; must be a multiple of this DStream's interval. + * @return + */ def window(windowTime: Time): DStream[T] = window(windowTime, this.slideTime) + /** + * Return a new DStream which is computed based on windowed batches of this DStream. + * @param windowTime duration (i.e., width) of the window; + * must be a multiple of this DStream's interval + * @param slideTime sliding interval of the window (i.e., the interval after which + * the new DStream will generate RDDs); must be a multiple of this + * DStream's interval + */ def window(windowTime: Time, slideTime: Time): DStream[T] = { new WindowedDStream(this, windowTime, slideTime) } + /** + * Returns a new DStream which computed based on tumbling window on this DStream. + * This is equivalent to window(batchTime, batchTime). + * @param batchTime tumbling window duration; must be a multiple of this DStream's interval + */ def tumble(batchTime: Time): DStream[T] = window(batchTime, batchTime) + /** + * Returns a new DStream in which each RDD has a single element generated by reducing all + * elements in a window over this DStream. windowTime and slideTime are as defined in the + * window() operation. This is equivalent to window(windowTime, slideTime).reduce(reduceFunc) + */ def reduceByWindow(reduceFunc: (T, T) => T, windowTime: Time, slideTime: Time): DStream[T] = { this.window(windowTime, slideTime).reduce(reduceFunc) } @@ -516,17 +574,31 @@ extends Serializable with Logging { .map(_._2) } + /** + * Returns a new DStream in which each RDD has a single element generated by counting the number + * of elements in a window over this DStream. windowTime and slideTime are as defined in the + * window() operation. This is equivalent to window(windowTime, slideTime).count() + */ def countByWindow(windowTime: Time, slideTime: Time): DStream[Int] = { this.map(_ => 1).reduceByWindow(_ + _, _ - _, windowTime, slideTime) } + /** + * Returns a new DStream by unifying data of another DStream with this DStream. + * @param that Another DStream having the same interval (i.e., slideTime) as this DStream. + */ def union(that: DStream[T]): DStream[T] = new UnionDStream[T](Array(this, that)) - def slice(interval: Interval): Seq[RDD[T]] = { + /** + * Returns all the RDDs defined by the Interval object (both end times included) + */ + protected[streaming] def slice(interval: Interval): Seq[RDD[T]] = { slice(interval.beginTime, interval.endTime) } - // Get all the RDDs between fromTime to toTime (both included) + /** + * Returns all the RDDs between 'fromTime' to 'toTime' (both included) + */ def slice(fromTime: Time, toTime: Time): Seq[RDD[T]] = { val rdds = new ArrayBuffer[RDD[T]]() var time = toTime.floor(slideTime) @@ -540,20 +612,26 @@ extends Serializable with Logging { rdds.toSeq } + /** + * Saves each RDD in this DStream as a Sequence file of serialized objects. + */ def saveAsObjectFiles(prefix: String, suffix: String = "") { val saveFunc = (rdd: RDD[T], time: Time) => { val file = rddToFileName(prefix, suffix, time) rdd.saveAsObjectFile(file) } - this.foreachRDD(saveFunc) + this.foreach(saveFunc) } + /** + * Saves each RDD in this DStream as at text file, using string representation of elements. + */ def saveAsTextFiles(prefix: String, suffix: String = "") { val saveFunc = (rdd: RDD[T], time: Time) => { val file = rddToFileName(prefix, suffix, time) rdd.saveAsTextFile(file) } - this.foreachRDD(saveFunc) + this.foreach(saveFunc) } def register() { @@ -561,6 +639,8 @@ extends Serializable with Logging { } } +private[streaming] +case class DStreamCheckpointData(rdds: HashMap[Time, Any]) abstract class InputDStream[T: ClassManifest] (@transient ssc_ : StreamingContext) extends DStream[T](ssc_) { @@ -583,6 +663,7 @@ abstract class InputDStream[T: ClassManifest] (@transient ssc_ : StreamingContex * TODO */ +private[streaming] class MappedDStream[T: ClassManifest, U: ClassManifest] ( parent: DStream[T], mapFunc: T => U @@ -602,6 +683,7 @@ class MappedDStream[T: ClassManifest, U: ClassManifest] ( * TODO */ +private[streaming] class FlatMappedDStream[T: ClassManifest, U: ClassManifest]( parent: DStream[T], flatMapFunc: T => Traversable[U] @@ -621,6 +703,7 @@ class FlatMappedDStream[T: ClassManifest, U: ClassManifest]( * TODO */ +private[streaming] class FilteredDStream[T: ClassManifest]( parent: DStream[T], filterFunc: T => Boolean @@ -640,9 +723,11 @@ class FilteredDStream[T: ClassManifest]( * TODO */ +private[streaming] class MapPartitionedDStream[T: ClassManifest, U: ClassManifest]( parent: DStream[T], - mapPartFunc: Iterator[T] => Iterator[U] + mapPartFunc: Iterator[T] => Iterator[U], + preservePartitioning: Boolean ) extends DStream[U](parent.ssc) { override def dependencies = List(parent) @@ -650,7 +735,7 @@ class MapPartitionedDStream[T: ClassManifest, U: ClassManifest]( override def slideTime: Time = parent.slideTime override def compute(validTime: Time): Option[RDD[U]] = { - parent.getOrCompute(validTime).map(_.mapPartitions[U](mapPartFunc)) + parent.getOrCompute(validTime).map(_.mapPartitions[U](mapPartFunc, preservePartitioning)) } } @@ -659,6 +744,7 @@ class MapPartitionedDStream[T: ClassManifest, U: ClassManifest]( * TODO */ +private[streaming] class GlommedDStream[T: ClassManifest](parent: DStream[T]) extends DStream[Array[T]](parent.ssc) { @@ -676,6 +762,7 @@ class GlommedDStream[T: ClassManifest](parent: DStream[T]) * TODO */ +private[streaming] class ShuffledDStream[K: ClassManifest, V: ClassManifest, C: ClassManifest]( parent: DStream[(K,V)], createCombiner: V => C, @@ -702,6 +789,7 @@ class ShuffledDStream[K: ClassManifest, V: ClassManifest, C: ClassManifest]( * TODO */ +private[streaming] class MapValuesDStream[K: ClassManifest, V: ClassManifest, U: ClassManifest]( parent: DStream[(K, V)], mapValueFunc: V => U @@ -720,7 +808,7 @@ class MapValuesDStream[K: ClassManifest, V: ClassManifest, U: ClassManifest]( /** * TODO */ - +private[streaming] class FlatMapValuesDStream[K: ClassManifest, V: ClassManifest, U: ClassManifest]( parent: DStream[(K, V)], flatMapValueFunc: V => TraversableOnce[U] @@ -779,38 +867,8 @@ class UnionDStream[T: ClassManifest](parents: Array[DStream[T]]) * TODO */ -class PerElementForEachDStream[T: ClassManifest] ( - parent: DStream[T], - foreachFunc: T => Unit - ) extends DStream[Unit](parent.ssc) { - - override def dependencies = List(parent) - - override def slideTime: Time = parent.slideTime - - override def compute(validTime: Time): Option[RDD[Unit]] = None - - override def generateJob(time: Time): Option[Job] = { - parent.getOrCompute(time) match { - case Some(rdd) => - val jobFunc = () => { - val sparkJobFunc = { - (iterator: Iterator[T]) => iterator.foreach(foreachFunc) - } - ssc.sc.runJob(rdd, sparkJobFunc) - } - Some(new Job(time, jobFunc)) - case None => None - } - } -} - - -/** - * TODO - */ - -class PerRDDForEachDStream[T: ClassManifest] ( +private[streaming] +class ForEachDStream[T: ClassManifest] ( parent: DStream[T], foreachFunc: (RDD[T], Time) => Unit ) extends DStream[Unit](parent.ssc) { @@ -838,6 +896,7 @@ class PerRDDForEachDStream[T: ClassManifest] ( * TODO */ +private[streaming] class TransformedDStream[T: ClassManifest, U: ClassManifest] ( parent: DStream[T], transformFunc: (RDD[T], Time) => RDD[U] diff --git a/streaming/src/main/scala/spark/streaming/FlumeInputDStream.scala b/streaming/src/main/scala/spark/streaming/FlumeInputDStream.scala index 2959ce4540..5ac7e5b08e 100644 --- a/streaming/src/main/scala/spark/streaming/FlumeInputDStream.scala +++ b/streaming/src/main/scala/spark/streaming/FlumeInputDStream.scala @@ -79,7 +79,7 @@ class SparkFlumeEvent() extends Externalizable { } } -object SparkFlumeEvent { +private[streaming] object SparkFlumeEvent { def fromAvroFlumeEvent(in : AvroFlumeEvent) : SparkFlumeEvent = { val event = new SparkFlumeEvent event.event = in diff --git a/streaming/src/main/scala/spark/streaming/Interval.scala b/streaming/src/main/scala/spark/streaming/Interval.scala index ffb7725ac9..fa0b7ce19d 100644 --- a/streaming/src/main/scala/spark/streaming/Interval.scala +++ b/streaming/src/main/scala/spark/streaming/Interval.scala @@ -1,5 +1,6 @@ package spark.streaming +private[streaming] case class Interval(beginTime: Time, endTime: Time) { def this(beginMs: Long, endMs: Long) = this(Time(beginMs), new Time(endMs)) diff --git a/streaming/src/main/scala/spark/streaming/Job.scala b/streaming/src/main/scala/spark/streaming/Job.scala index 0bcb6fd8dc..67bd8388bc 100644 --- a/streaming/src/main/scala/spark/streaming/Job.scala +++ b/streaming/src/main/scala/spark/streaming/Job.scala @@ -2,6 +2,7 @@ package spark.streaming import java.util.concurrent.atomic.AtomicLong +private[streaming] class Job(val time: Time, func: () => _) { val id = Job.getNewId() def run(): Long = { @@ -14,6 +15,7 @@ class Job(val time: Time, func: () => _) { override def toString = "streaming job " + id + " @ " + time } +private[streaming] object Job { val id = new AtomicLong(0) diff --git a/streaming/src/main/scala/spark/streaming/JobManager.scala b/streaming/src/main/scala/spark/streaming/JobManager.scala index 9bf9251519..fda7264a27 100644 --- a/streaming/src/main/scala/spark/streaming/JobManager.scala +++ b/streaming/src/main/scala/spark/streaming/JobManager.scala @@ -5,6 +5,7 @@ import spark.SparkEnv import java.util.concurrent.Executors +private[streaming] class JobManager(ssc: StreamingContext, numThreads: Int = 1) extends Logging { class JobHandler(ssc: StreamingContext, job: Job) extends Runnable { diff --git a/streaming/src/main/scala/spark/streaming/NetworkInputDStream.scala b/streaming/src/main/scala/spark/streaming/NetworkInputDStream.scala index 4e4e9fc942..4bf13dd50c 100644 --- a/streaming/src/main/scala/spark/streaming/NetworkInputDStream.scala +++ b/streaming/src/main/scala/spark/streaming/NetworkInputDStream.scala @@ -40,10 +40,10 @@ abstract class NetworkInputDStream[T: ClassManifest](@transient ssc_ : Streaming } -sealed trait NetworkReceiverMessage -case class StopReceiver(msg: String) extends NetworkReceiverMessage -case class ReportBlock(blockId: String, metadata: Any) extends NetworkReceiverMessage -case class ReportError(msg: String) extends NetworkReceiverMessage +private[streaming] sealed trait NetworkReceiverMessage +private[streaming] case class StopReceiver(msg: String) extends NetworkReceiverMessage +private[streaming] case class ReportBlock(blockId: String, metadata: Any) extends NetworkReceiverMessage +private[streaming] case class ReportError(msg: String) extends NetworkReceiverMessage abstract class NetworkReceiver[T: ClassManifest](val streamId: Int) extends Serializable with Logging { diff --git a/streaming/src/main/scala/spark/streaming/NetworkInputTracker.scala b/streaming/src/main/scala/spark/streaming/NetworkInputTracker.scala index b421f795ee..658498dfc1 100644 --- a/streaming/src/main/scala/spark/streaming/NetworkInputTracker.scala +++ b/streaming/src/main/scala/spark/streaming/NetworkInputTracker.scala @@ -11,10 +11,10 @@ import akka.pattern.ask import akka.util.duration._ import akka.dispatch._ -trait NetworkInputTrackerMessage -case class RegisterReceiver(streamId: Int, receiverActor: ActorRef) extends NetworkInputTrackerMessage -case class AddBlocks(streamId: Int, blockIds: Seq[String], metadata: Any) extends NetworkInputTrackerMessage -case class DeregisterReceiver(streamId: Int, msg: String) extends NetworkInputTrackerMessage +private[streaming] sealed trait NetworkInputTrackerMessage +private[streaming] case class RegisterReceiver(streamId: Int, receiverActor: ActorRef) extends NetworkInputTrackerMessage +private[streaming] case class AddBlocks(streamId: Int, blockIds: Seq[String], metadata: Any) extends NetworkInputTrackerMessage +private[streaming] case class DeregisterReceiver(streamId: Int, msg: String) extends NetworkInputTrackerMessage class NetworkInputTracker( diff --git a/streaming/src/main/scala/spark/streaming/PairDStreamFunctions.scala b/streaming/src/main/scala/spark/streaming/PairDStreamFunctions.scala index 720e63bba0..f9fef14196 100644 --- a/streaming/src/main/scala/spark/streaming/PairDStreamFunctions.scala +++ b/streaming/src/main/scala/spark/streaming/PairDStreamFunctions.scala @@ -281,7 +281,7 @@ extends Serializable { val file = rddToFileName(prefix, suffix, time) rdd.saveAsHadoopFile(file, keyClass, valueClass, outputFormatClass, conf) } - self.foreachRDD(saveFunc) + self.foreach(saveFunc) } def saveAsNewAPIHadoopFiles[F <: NewOutputFormat[K, V]]( @@ -303,7 +303,7 @@ extends Serializable { val file = rddToFileName(prefix, suffix, time) rdd.saveAsNewAPIHadoopFile(file, keyClass, valueClass, outputFormatClass, conf) } - self.foreachRDD(saveFunc) + self.foreach(saveFunc) } private def getKeyClass() = implicitly[ClassManifest[K]].erasure diff --git a/streaming/src/main/scala/spark/streaming/Scheduler.scala b/streaming/src/main/scala/spark/streaming/Scheduler.scala index 014021be61..fd1fa77a24 100644 --- a/streaming/src/main/scala/spark/streaming/Scheduler.scala +++ b/streaming/src/main/scala/spark/streaming/Scheduler.scala @@ -7,11 +7,8 @@ import spark.Logging import scala.collection.mutable.HashMap -sealed trait SchedulerMessage -case class InputGenerated(inputName: String, interval: Interval, reference: AnyRef = null) extends SchedulerMessage - -class Scheduler(ssc: StreamingContext) -extends Logging { +private[streaming] +class Scheduler(ssc: StreamingContext) extends Logging { initLogging() diff --git a/streaming/src/main/scala/spark/streaming/StreamingContext.scala b/streaming/src/main/scala/spark/streaming/StreamingContext.scala index ce47bcb2da..998fea849f 100644 --- a/streaming/src/main/scala/spark/streaming/StreamingContext.scala +++ b/streaming/src/main/scala/spark/streaming/StreamingContext.scala @@ -48,7 +48,7 @@ class StreamingContext private ( this(StreamingContext.createNewSparkContext(master, frameworkName), null, batchDuration) /** - * Recreates the StreamingContext from a checkpoint file. + * Re-creates a StreamingContext from a checkpoint file. * @param path Path either to the directory that was specified as the checkpoint directory, or * to the checkpoint file 'graph' or 'graph.bk'. */ @@ -61,7 +61,7 @@ class StreamingContext private ( "both SparkContext and checkpoint as null") } - val isCheckpointPresent = (cp_ != null) + protected[streaming] val isCheckpointPresent = (cp_ != null) val sc: SparkContext = { if (isCheckpointPresent) { @@ -71,9 +71,9 @@ class StreamingContext private ( } } - val env = SparkEnv.get + protected[streaming] val env = SparkEnv.get - val graph: DStreamGraph = { + protected[streaming] val graph: DStreamGraph = { if (isCheckpointPresent) { cp_.graph.setContext(this) cp_.graph.restoreCheckpointData() @@ -86,10 +86,10 @@ class StreamingContext private ( } } - private[streaming] val nextNetworkInputStreamId = new AtomicInteger(0) - private[streaming] var networkInputTracker: NetworkInputTracker = null + protected[streaming] val nextNetworkInputStreamId = new AtomicInteger(0) + protected[streaming] var networkInputTracker: NetworkInputTracker = null - private[streaming] var checkpointDir: String = { + protected[streaming] var checkpointDir: String = { if (isCheckpointPresent) { sc.setCheckpointDir(StreamingContext.getSparkCheckpointDir(cp_.checkpointDir), true) cp_.checkpointDir @@ -98,9 +98,9 @@ class StreamingContext private ( } } - private[streaming] var checkpointInterval: Time = if (isCheckpointPresent) cp_.checkpointInterval else null - private[streaming] var receiverJobThread: Thread = null - private[streaming] var scheduler: Scheduler = null + protected[streaming] var checkpointInterval: Time = if (isCheckpointPresent) cp_.checkpointInterval else null + protected[streaming] var receiverJobThread: Thread = null + protected[streaming] var scheduler: Scheduler = null def remember(duration: Time) { graph.remember(duration) @@ -117,11 +117,11 @@ class StreamingContext private ( } } - private[streaming] def getInitialCheckpoint(): Checkpoint = { + protected[streaming] def getInitialCheckpoint(): Checkpoint = { if (isCheckpointPresent) cp_ else null } - private[streaming] def getNewNetworkStreamId() = nextNetworkInputStreamId.getAndIncrement() + protected[streaming] def getNewNetworkStreamId() = nextNetworkInputStreamId.getAndIncrement() /** * Create an input stream that pulls messages form a Kafka Broker. @@ -188,7 +188,7 @@ class StreamingContext private ( } /** - * This function creates a input stream that monitors a Hadoop-compatible filesystem + * Creates a input stream that monitors a Hadoop-compatible filesystem * for new files and executes the necessary processing on them. */ def fileStream[ @@ -206,7 +206,7 @@ class StreamingContext private ( } /** - * This function create a input stream from an queue of RDDs. In each batch, + * Creates a input stream from an queue of RDDs. In each batch, * it will process either one or all of the RDDs returned by the queue */ def queueStream[T: ClassManifest]( @@ -231,22 +231,21 @@ class StreamingContext private ( } /** - * This function registers a InputDStream as an input stream that will be - * started (InputDStream.start() called) to get the input data streams. + * Registers an input stream that will be started (InputDStream.start() called) to get the + * input data. */ def registerInputStream(inputStream: InputDStream[_]) { graph.addInputStream(inputStream) } /** - * This function registers a DStream as an output stream that will be - * computed every interval. + * Registers an output stream that will be computed every interval */ def registerOutputStream(outputStream: DStream[_]) { graph.addOutputStream(outputStream) } - def validate() { + protected def validate() { assert(graph != null, "Graph is null") graph.validate() @@ -304,7 +303,7 @@ class StreamingContext private ( object StreamingContext { - def createNewSparkContext(master: String, frameworkName: String): SparkContext = { + protected[streaming] def createNewSparkContext(master: String, frameworkName: String): SparkContext = { // Set the default cleaner delay to an hour if not already set. // This should be sufficient for even 1 second interval. @@ -318,7 +317,7 @@ object StreamingContext { new PairDStreamFunctions[K, V](stream) } - def rddToFileName[T](prefix: String, suffix: String, time: Time): String = { + protected[streaming] def rddToFileName[T](prefix: String, suffix: String, time: Time): String = { if (prefix == null) { time.millis.toString } else if (suffix == null || suffix.length ==0) { @@ -328,7 +327,7 @@ object StreamingContext { } } - def getSparkCheckpointDir(sscCheckpointDir: String): String = { + protected[streaming] def getSparkCheckpointDir(sscCheckpointDir: String): String = { new Path(sscCheckpointDir, UUID.randomUUID.toString).toString } } diff --git a/streaming/src/main/scala/spark/streaming/examples/GrepRaw.scala b/streaming/src/main/scala/spark/streaming/examples/GrepRaw.scala index 6cb2b4c042..7c4ee3b34c 100644 --- a/streaming/src/main/scala/spark/streaming/examples/GrepRaw.scala +++ b/streaming/src/main/scala/spark/streaming/examples/GrepRaw.scala @@ -26,7 +26,7 @@ object GrepRaw { val rawStreams = (1 to numStreams).map(_ => ssc.rawNetworkStream[String](host, port, StorageLevel.MEMORY_ONLY_SER_2)).toArray val union = new UnionDStream(rawStreams) - union.filter(_.contains("Alice")).count().foreachRDD(r => + union.filter(_.contains("Alice")).count().foreach(r => println("Grep count: " + r.collect().mkString)) ssc.start() } diff --git a/streaming/src/main/scala/spark/streaming/examples/TopKWordCountRaw.scala b/streaming/src/main/scala/spark/streaming/examples/TopKWordCountRaw.scala index fe4c2bf155..182dfd8a52 100644 --- a/streaming/src/main/scala/spark/streaming/examples/TopKWordCountRaw.scala +++ b/streaming/src/main/scala/spark/streaming/examples/TopKWordCountRaw.scala @@ -38,7 +38,7 @@ object TopKWordCountRaw { val counts = union.mapPartitions(splitAndCountPartitions) val windowedCounts = counts.reduceByKeyAndWindow(add _, subtract _, Seconds(30), Seconds(1), 10) val partialTopKWindowedCounts = windowedCounts.mapPartitions(topK(_, k)) - partialTopKWindowedCounts.foreachRDD(rdd => { + partialTopKWindowedCounts.foreach(rdd => { val collectedCounts = rdd.collect println("Collected " + collectedCounts.size + " words from partial top words") println("Top " + k + " words are " + topK(collectedCounts.toIterator, k).mkString(",")) diff --git a/streaming/src/main/scala/spark/streaming/examples/WordCountRaw.scala b/streaming/src/main/scala/spark/streaming/examples/WordCountRaw.scala index a29c81d437..9bcd30f4d7 100644 --- a/streaming/src/main/scala/spark/streaming/examples/WordCountRaw.scala +++ b/streaming/src/main/scala/spark/streaming/examples/WordCountRaw.scala @@ -36,7 +36,7 @@ object WordCountRaw { val union = new UnionDStream(lines.toArray) val counts = union.mapPartitions(splitAndCountPartitions) val windowedCounts = counts.reduceByKeyAndWindow(add _, subtract _, Seconds(30), Seconds(1), 10) - windowedCounts.foreachRDD(r => println("# unique words = " + r.count())) + windowedCounts.foreach(r => println("# unique words = " + r.count())) ssc.start() } diff --git a/streaming/src/main/scala/spark/streaming/examples/clickstream/PageViewStream.scala b/streaming/src/main/scala/spark/streaming/examples/clickstream/PageViewStream.scala index 68be6b7893..a191321d91 100644 --- a/streaming/src/main/scala/spark/streaming/examples/clickstream/PageViewStream.scala +++ b/streaming/src/main/scala/spark/streaming/examples/clickstream/PageViewStream.scala @@ -72,7 +72,7 @@ object PageViewStream { case "popularUsersSeen" => // Look for users in our existing dataset and print it out if we have a match pageViews.map(view => (view.userID, 1)) - .foreachRDD((rdd, time) => rdd.join(userList) + .foreach((rdd, time) => rdd.join(userList) .map(_._2._2) .take(10) .foreach(u => println("Saw user %s at time %s".format(u, time)))) diff --git a/streaming/src/test/scala/spark/streaming/TestSuiteBase.scala b/streaming/src/test/scala/spark/streaming/TestSuiteBase.scala index 8cc2f8ccfc..a44f738957 100644 --- a/streaming/src/test/scala/spark/streaming/TestSuiteBase.scala +++ b/streaming/src/test/scala/spark/streaming/TestSuiteBase.scala @@ -35,7 +35,7 @@ class TestInputStream[T: ClassManifest](ssc_ : StreamingContext, input: Seq[Seq[ * ArrayBuffer. This buffer is wiped clean on being restored from checkpoint. */ class TestOutputStream[T: ClassManifest](parent: DStream[T], val output: ArrayBuffer[Seq[T]]) - extends PerRDDForEachDStream[T](parent, (rdd: RDD[T], t: Time) => { + extends ForEachDStream[T](parent, (rdd: RDD[T], t: Time) => { val collected = rdd.collect() output += collected }) { |