For outputformats that are Configurable, call setConf before sending …

…data to them.

[SPARK-1108] This allows us to use, e.g. HBase's TableOutputFormat with PairRDDFunctions.saveAsNewAPIHadoopFile, which otherwise would throw NullPointerException because the output table name hasn't been configured.

Note this bug also affects branch-0.9

Author: Bryn Keller <bryn.keller@intel.com>

Closes #638 from xoltar/SPARK-1108 and squashes the following commits:

7e94e7d [Bryn Keller] Import, comment, and format cleanup per code review
7cbcaa1 [Bryn Keller] For outputformats that are Configurable, call setConf before sending data to them. This allows us to use, e.g. HBase TableOutputFormat, which otherwise would throw NullPointerException because the output table name hasn't been configured

core/src/main/scala/org/apache/spark/rdd/PairRDDFunctions.scala

@@ -29,7 +29,7 @@ import scala.collection.mutable.ArrayBuffer
 import scala.reflect.ClassTag
 
 import com.clearspring.analytics.stream.cardinality.HyperLogLog
-import org.apache.hadoop.conf.Configuration
+import org.apache.hadoop.conf.{Configurable, Configuration}
 import org.apache.hadoop.fs.Path
 import org.apache.hadoop.io.SequenceFile.CompressionType
 import org.apache.hadoop.io.compress.CompressionCodec
@@ -618,6 +618,10 @@ class PairRDDFunctions[K: ClassTag, V: ClassTag](self: RDD[(K, V)])
         attemptNumber)
       val hadoopContext = newTaskAttemptContext(wrappedConf.value, attemptId)
       val format = outputFormatClass.newInstance
+      format match {
+        case c: Configurable => c.setConf(wrappedConf.value)
+        case _ => ()
+      }
       val committer = format.getOutputCommitter(hadoopContext)
       committer.setupTask(hadoopContext)
       val writer = format.getRecordWriter(hadoopContext).asInstanceOf[NewRecordWriter[K,V]]

core/src/test/scala/org/apache/spark/rdd/PairRDDFunctionsSuite.scala

@@ -23,6 +23,8 @@ import scala.util.Random
 
 import org.scalatest.FunSuite
 import com.google.common.io.Files
+import org.apache.hadoop.mapreduce._
+import org.apache.hadoop.conf.{Configuration, Configurable}
 
 import org.apache.spark.SparkContext._
 import org.apache.spark.{Partitioner, SharedSparkContext}
@@ -330,4 +332,77 @@ class PairRDDFunctionsSuite extends FunSuite with SharedSparkContext {
       (1, ArrayBuffer(1)),
       (2, ArrayBuffer(1))))
   }
+
+  test("saveNewAPIHadoopFile should call setConf if format is configurable") {
+    val pairs = sc.parallelize(Array((new Integer(1), new Integer(1))))
+
+    // No error, non-configurable formats still work
+    pairs.saveAsNewAPIHadoopFile[FakeFormat]("ignored")
+
+    /*
+      Check that configurable formats get configured:
+      ConfigTestFormat throws an exception if we try to write
+      to it when setConf hasn't been called first.
+      Assertion is in ConfigTestFormat.getRecordWriter.
+     */
+    pairs.saveAsNewAPIHadoopFile[ConfigTestFormat]("ignored")
+  }
 }
+
+/*
+  These classes are fakes for testing
+    "saveNewAPIHadoopFile should call setConf if format is configurable".
+  Unfortunately, they have to be top level classes, and not defined in
+  the test method, because otherwise Scala won't generate no-args constructors
+  and the test will therefore throw InstantiationException when saveAsNewAPIHadoopFile
+  tries to instantiate them with Class.newInstance.
+ */
+class FakeWriter extends RecordWriter[Integer, Integer] {
+
+  def close(p1: TaskAttemptContext) = ()
+
+  def write(p1: Integer, p2: Integer) = ()
+
+}
+
+class FakeCommitter extends OutputCommitter {
+  def setupJob(p1: JobContext) = ()
+
+  def needsTaskCommit(p1: TaskAttemptContext): Boolean = false
+
+  def setupTask(p1: TaskAttemptContext) = ()
+
+  def commitTask(p1: TaskAttemptContext) = ()
+
+  def abortTask(p1: TaskAttemptContext) = ()
+}
+
+class FakeFormat() extends OutputFormat[Integer, Integer]() {
+
+  def checkOutputSpecs(p1: JobContext)  = ()
+
+  def getRecordWriter(p1: TaskAttemptContext): RecordWriter[Integer, Integer] = {
+    new FakeWriter()
+  }
+
+  def getOutputCommitter(p1: TaskAttemptContext): OutputCommitter = {
+    new FakeCommitter()
+  }
+}
+
+class ConfigTestFormat() extends FakeFormat() with Configurable {
+
+  var setConfCalled = false
+  def setConf(p1: Configuration) = {
+    setConfCalled = true
+    ()
+  }
+
+  def getConf: Configuration = null
+
+  override def getRecordWriter(p1: TaskAttemptContext): RecordWriter[Integer, Integer] = {
+    assert(setConfCalled, "setConf was never called")
+    super.getRecordWriter(p1)
+  }
+}
+