Merge pull request #199 from harveyfeng/yarn-2.2

Hadoop 2.2 migration

Includes support for the YARN API stabilized in the Hadoop 2.2 release, and a few style patches.

Short description for each set of commits:

a98f5a0 - "Misc style changes in the 'yarn' package"
a67ebf4 - "A few more style fixes in the 'yarn' package"
Both of these are some minor style changes, such as fixing lines over 100 chars, to the existing YARN code.

ab8652f - "Add a 'new-yarn' directory ... "
Copies everything from `SPARK_HOME/yarn` to `SPARK_HOME/new-yarn`. No actual code changes here.

4f1c3fa - "Hadoop 2.2 YARN API migration ..."
API patches to code in the `SPARK_HOME/new-yarn` directory. There are a few more small style changes mixed in, too.
Based on @colorant's Hadoop 2.2 support for the scala-2.10 branch in #141.

a1a1c62 - "Add optional Hadoop 2.2 settings in sbt build ... "
If Spark should be built against Hadoop 2.2, then:
a) the `org.apache.spark.deploy.yarn` package will be compiled from the `new-yarn` directory.
b) Protobuf v2.5 will be used as a Spark dependency, since Hadoop 2.2 depends on it. Also, Spark will be built against a version of Akka v2.0.5 that's built against Protobuf 2.5, named `akka-2.0.5-protobuf-2.5`. The patched Akka is here: https://github.com/harveyfeng/akka/tree/2.0.5-protobuf-2.5, and was published to local Ivy during testing.

There's also a new boolean environment variable, `SPARK_IS_NEW_HADOOP`, that users can manually set if their `SPARK_HADOOP_VERSION` specification does not start with `2.2`, which is how the build file tries to detect a 2.2 version. Not sure if this is necessary or done in the best way, though...

2 files changed, 4 insertions, 8 deletions

diff --git a/core/pom.xml b/core/pom.xml
index 6af229c71d..38f4be1280 100644
--- a/core/pom.xml
+++ b/core/pom.xml
@@ -95,15 +95,15 @@
       <version>0.3.1</version>
     </dependency>
     <dependency>
-      <groupId>com.typesafe.akka</groupId>
+      <groupId>${akka.group}</groupId>
       <artifactId>akka-actor</artifactId>
     </dependency>
     <dependency>
-      <groupId>com.typesafe.akka</groupId>
+      <groupId>${akka.group}</groupId>
       <artifactId>akka-remote</artifactId>
     </dependency>
     <dependency>
-      <groupId>com.typesafe.akka</groupId>
+      <groupId>${akka.group}</groupId>
       <artifactId>akka-slf4j</artifactId>
     </dependency>
     <dependency>
@@ -127,10 +127,6 @@
       <artifactId>colt</artifactId>
     </dependency>
     <dependency>
-      <groupId>com.github.scala-incubator.io</groupId>
-      <artifactId>scala-io-file_2.9.2</artifactId>
-    </dependency>
-    <dependency>
       <groupId>org.apache.mesos</groupId>
       <artifactId>mesos</artifactId>
     </dependency>
diff --git a/core/src/main/scala/org/apache/spark/SparkContext.scala b/core/src/main/scala/org/apache/spark/SparkContext.scala
index 3da13133da..66006bf212 100644
--- a/core/src/main/scala/org/apache/spark/SparkContext.scala
+++ b/core/src/main/scala/org/apache/spark/SparkContext.scala
@@ -81,7 +81,7 @@ class SparkContext(
     val sparkHome: String = null,
     val jars: Seq[String] = Nil,
     val environment: Map[String, String] = Map(),
-    // This is used only by yarn for now, but should be relevant to other cluster types (mesos, etc)
+    // This is used only by YARN for now, but should be relevant to other cluster types (Mesos, etc)
     // too. This is typically generated from InputFormatInfo.computePreferredLocations .. host, set
     // of data-local splits on host
     val preferredNodeLocationData: scala.collection.Map[String, scala.collection.Set[SplitInfo]] =