[SPARK-1010] Clean up uses of System.setProperty in unit tests

Several of our tests call System.setProperty (or test code which implicitly sets system properties) and don't always reset/clear the modified properties, which can create ordering dependencies between tests and cause hard-to-diagnose failures.

This patch removes most uses of System.setProperty from our tests, since in most cases we can use SparkConf to set these configurations (there are a few exceptions, including the tests of SparkConf itself).

For the cases where we continue to use System.setProperty, this patch introduces a `ResetSystemProperties` ScalaTest mixin class which snapshots the system properties before individual tests and to automatically restores them on test completion / failure.  See the block comment at the top of the ResetSystemProperties class for more details.

Author: Josh Rosen <[email protected]>

Closes #3739 from JoshRosen/cleanup-system-properties-in-tests and squashes the following commits:

0236d66 [Josh Rosen] Replace setProperty uses in two example programs / tools
3888fe3 [Josh Rosen] Remove setProperty use in LocalJavaStreamingContext
4f4031d [Josh Rosen] Add note on why SparkSubmitSuite needs ResetSystemProperties
4742a5b [Josh Rosen] Clarify ResetSystemProperties trait inheritance ordering.
0eaf0b6 [Josh Rosen] Remove setProperty call in TaskResultGetterSuite.
7a3d224 [Josh Rosen] Fix trait ordering
3fdb554 [Josh Rosen] Remove setProperty call in TaskSchedulerImplSuite
bee20df [Josh Rosen] Remove setProperty calls in SparkContextSchedulerCreationSuite
655587c [Josh Rosen] Remove setProperty calls in JobCancellationSuite
3f2f955 [Josh Rosen] Remove System.setProperty calls in DistributedSuite
cfe9cce [Josh Rosen] Remove use of system properties in SparkContextSuite
8783ab0 [Josh Rosen] Remove TestUtils.setSystemProperty, since it is subsumed by the ResetSystemProperties trait.
633a84a [Josh Rosen] Remove use of system properties in FileServerSuite
25bfce2 [Josh Rosen] Use ResetSystemProperties in UtilsSuite
1d1aa5a [Josh Rosen] Use ResetSystemProperties in SizeEstimatorSuite
dd9492b [Josh Rosen] Use ResetSystemProperties in AkkaUtilsSuite
b0daff2 [Josh Rosen] Use ResetSystemProperties in BlockManagerSuite
e9ded62 [Josh Rosen] Use ResetSystemProperties in TaskSchedulerImplSuite
5b3cb54 [Josh Rosen] Use ResetSystemProperties in SparkListenerSuite
0995c4b [Josh Rosen] Use ResetSystemProperties in SparkContextSchedulerCreationSuite
c83ded8 [Josh Rosen] Use ResetSystemProperties in SparkConfSuite
51aa870 [Josh Rosen] Use withSystemProperty in ShuffleSuite
60a63a1 [Josh Rosen] Use ResetSystemProperties in JobCancellationSuite
14a92e4 [Josh Rosen] Use withSystemProperty in FileServerSuite
628f46c [Josh Rosen] Use ResetSystemProperties in DistributedSuite
9e3e0dd [Josh Rosen] Add ResetSystemProperties test fixture mixin; use it in SparkSubmitSuite.
4dcea38 [Josh Rosen] Move withSystemProperty to TestUtils class.

Author: JoshRosen

core/src/test/scala/org/apache/spark/DistributedSuite.scala

@@ -17,7 +17,6 @@
 
 package org.apache.spark
 
-import org.scalatest.BeforeAndAfter
 import org.scalatest.FunSuite
 import org.scalatest.concurrent.Timeouts._
 import org.scalatest.Matchers
@@ -29,16 +28,10 @@ class NotSerializableClass
 class NotSerializableExn(val notSer: NotSerializableClass) extends Throwable() {}
 
 
-class DistributedSuite extends FunSuite with Matchers with BeforeAndAfter
-  with LocalSparkContext {
+class DistributedSuite extends FunSuite with Matchers with LocalSparkContext {
 
   val clusterUrl = "local-cluster[2,1,512]"
 
-  after {
-    System.clearProperty("spark.reducer.maxMbInFlight")
-    System.clearProperty("spark.storage.memoryFraction")
-  }
-
   test("task throws not serializable exception") {
     // Ensures that executors do not crash when an exn is not serializable. If executors crash,
     // this test will hang. Correct behavior is that executors don't crash but fail tasks
@@ -84,15 +77,14 @@ class DistributedSuite extends FunSuite with Matchers with BeforeAndAfter
   }
 
   test("groupByKey where map output sizes exceed maxMbInFlight") {
-    System.setProperty("spark.reducer.maxMbInFlight", "1")
-    sc = new SparkContext(clusterUrl, "test")
+    val conf = new SparkConf().set("spark.reducer.maxMbInFlight", "1")
+    sc = new SparkContext(clusterUrl, "test", conf)
     // This data should be around 20 MB, so even with 4 mappers and 2 reducers, each map output
     // file should be about 2.5 MB
     val pairs = sc.parallelize(1 to 2000, 4).map(x => (x % 16, new Array[Byte](10000)))
     val groups = pairs.groupByKey(2).map(x => (x._1, x._2.size)).collect()
     assert(groups.length === 16)
     assert(groups.map(_._2).sum === 2000)
-    // Note that spark.reducer.maxMbInFlight will be cleared in the test suite's after{} block
   }
 
   test("accumulators") {
@@ -210,28 +202,25 @@ class DistributedSuite extends FunSuite with Matchers with BeforeAndAfter
   }
 
   test("compute without caching when no partitions fit in memory") {
-    System.setProperty("spark.storage.memoryFraction", "0.0001")
     sc = new SparkContext(clusterUrl, "test")
     // data will be 4 million * 4 bytes = 16 MB in size, but our memoryFraction set the cache
     // to only 50 KB (0.0001 of 512 MB), so no partitions should fit in memory
     val data = sc.parallelize(1 to 4000000, 2).persist(StorageLevel.MEMORY_ONLY_SER)
     assert(data.count() === 4000000)
     assert(data.count() === 4000000)
     assert(data.count() === 4000000)
-    System.clearProperty("spark.storage.memoryFraction")
   }
 
   test("compute when only some partitions fit in memory") {
-    System.setProperty("spark.storage.memoryFraction", "0.01")
-    sc = new SparkContext(clusterUrl, "test")
+    val conf = new SparkConf().set("spark.storage.memoryFraction", "0.01")
+    sc = new SparkContext(clusterUrl, "test", conf)
     // data will be 4 million * 4 bytes = 16 MB in size, but our memoryFraction set the cache
     // to only 5 MB (0.01 of 512 MB), so not all of it will fit in memory; we use 20 partitions
     // to make sure that *some* of them do fit though
     val data = sc.parallelize(1 to 4000000, 20).persist(StorageLevel.MEMORY_ONLY_SER)
     assert(data.count() === 4000000)
     assert(data.count() === 4000000)
     assert(data.count() === 4000000)
-    System.clearProperty("spark.storage.memoryFraction")
   }
 
   test("passing environment variables to cluster") {

core/src/test/scala/org/apache/spark/FileServerSuite.scala

@@ -31,10 +31,11 @@ class FileServerSuite extends FunSuite with LocalSparkContext {
   @transient var tmpFile: File = _
   @transient var tmpJarUrl: String = _
 
+  def newConf: SparkConf = new SparkConf(loadDefaults = false).set("spark.authenticate", "false")
+
   override def beforeEach() {
     super.beforeEach()
     resetSparkContext()
-    System.setProperty("spark.authenticate", "false")
   }
 
   override def beforeAll() {
@@ -52,7 +53,6 @@ class FileServerSuite extends FunSuite with LocalSparkContext {
     val jarFile = new File(testTempDir, "test.jar")
     val jarStream = new FileOutputStream(jarFile)
     val jar = new JarOutputStream(jarStream, new java.util.jar.Manifest())
-    System.setProperty("spark.authenticate", "false")
 
     val jarEntry = new JarEntry(textFile.getName)
     jar.putNextEntry(jarEntry)
@@ -74,7 +74,7 @@ class FileServerSuite extends FunSuite with LocalSparkContext {
   }
 
   test("Distributing files locally") {
-    sc = new SparkContext("local[4]", "test")
+    sc = new SparkContext("local[4]", "test", newConf)
     sc.addFile(tmpFile.toString)
     val testData = Array((1,1), (1,1), (2,1), (3,5), (2,2), (3,0))
     val result = sc.parallelize(testData).reduceByKey {
@@ -108,7 +108,7 @@ class FileServerSuite extends FunSuite with LocalSparkContext {
 
   test("Distributing files locally using URL as input") {
     // addFile("file:///....")
-    sc = new SparkContext("local[4]", "test")
+    sc = new SparkContext("local[4]", "test", newConf)
     sc.addFile(new File(tmpFile.toString).toURI.toString)
     val testData = Array((1,1), (1,1), (2,1), (3,5), (2,2), (3,0))
     val result = sc.parallelize(testData).reduceByKey {
@@ -122,7 +122,7 @@ class FileServerSuite extends FunSuite with LocalSparkContext {
   }
 
   test ("Dynamically adding JARS locally") {
-    sc = new SparkContext("local[4]", "test")
+    sc = new SparkContext("local[4]", "test", newConf)
     sc.addJar(tmpJarUrl)
     val testData = Array((1, 1))
     sc.parallelize(testData).foreach { x =>
@@ -133,7 +133,7 @@ class FileServerSuite extends FunSuite with LocalSparkContext {
   }
 
   test("Distributing files on a standalone cluster") {
-    sc = new SparkContext("local-cluster[1,1,512]", "test")
+    sc = new SparkContext("local-cluster[1,1,512]", "test", newConf)
     sc.addFile(tmpFile.toString)
     val testData = Array((1,1), (1,1), (2,1), (3,5), (2,2), (3,0))
     val result = sc.parallelize(testData).reduceByKey {
@@ -147,7 +147,7 @@ class FileServerSuite extends FunSuite with LocalSparkContext {
   }
 
   test ("Dynamically adding JARS on a standalone cluster") {
-    sc = new SparkContext("local-cluster[1,1,512]", "test")
+    sc = new SparkContext("local-cluster[1,1,512]", "test", newConf)
     sc.addJar(tmpJarUrl)
     val testData = Array((1,1))
     sc.parallelize(testData).foreach { x =>
@@ -158,7 +158,7 @@ class FileServerSuite extends FunSuite with LocalSparkContext {
   }
 
   test ("Dynamically adding JARS on a standalone cluster using local: URL") {
-    sc = new SparkContext("local-cluster[1,1,512]", "test")
+    sc = new SparkContext("local-cluster[1,1,512]", "test", newConf)
     sc.addJar(tmpJarUrl.replace("file", "local"))
     val testData = Array((1,1))
     sc.parallelize(testData).foreach { x =>

core/src/test/scala/org/apache/spark/JobCancellationSuite.scala

@@ -40,43 +40,42 @@ class JobCancellationSuite extends FunSuite with Matchers with BeforeAndAfter
   override def afterEach() {
     super.afterEach()
     resetSparkContext()
-    System.clearProperty("spark.scheduler.mode")
   }
 
   test("local mode, FIFO scheduler") {
-    System.setProperty("spark.scheduler.mode", "FIFO")
-    sc = new SparkContext("local[2]", "test")
+    val conf = new SparkConf().set("spark.scheduler.mode", "FIFO")
+    sc = new SparkContext("local[2]", "test", conf)
     testCount()
     testTake()
     // Make sure we can still launch tasks.
     assert(sc.parallelize(1 to 10, 2).count === 10)
   }
 
   test("local mode, fair scheduler") {
-    System.setProperty("spark.scheduler.mode", "FAIR")
+    val conf = new SparkConf().set("spark.scheduler.mode", "FAIR")
     val xmlPath = getClass.getClassLoader.getResource("fairscheduler.xml").getFile()
-    System.setProperty("spark.scheduler.allocation.file", xmlPath)
-    sc = new SparkContext("local[2]", "test")
+    conf.set("spark.scheduler.allocation.file", xmlPath)
+    sc = new SparkContext("local[2]", "test", conf)
     testCount()
     testTake()
     // Make sure we can still launch tasks.
     assert(sc.parallelize(1 to 10, 2).count === 10)
   }
 
   test("cluster mode, FIFO scheduler") {
-    System.setProperty("spark.scheduler.mode", "FIFO")
-    sc = new SparkContext("local-cluster[2,1,512]", "test")
+    val conf = new SparkConf().set("spark.scheduler.mode", "FIFO")
+    sc = new SparkContext("local-cluster[2,1,512]", "test", conf)
     testCount()
     testTake()
     // Make sure we can still launch tasks.
     assert(sc.parallelize(1 to 10, 2).count === 10)
   }
 
   test("cluster mode, fair scheduler") {
-    System.setProperty("spark.scheduler.mode", "FAIR")
+    val conf = new SparkConf().set("spark.scheduler.mode", "FAIR")
     val xmlPath = getClass.getClassLoader.getResource("fairscheduler.xml").getFile()
-    System.setProperty("spark.scheduler.allocation.file", xmlPath)
-    sc = new SparkContext("local-cluster[2,1,512]", "test")
+    conf.set("spark.scheduler.allocation.file", xmlPath)
+    sc = new SparkContext("local-cluster[2,1,512]", "test", conf)
     testCount()
     testTake()
     // Make sure we can still launch tasks.

core/src/test/scala/org/apache/spark/ShuffleSuite.scala

@@ -35,19 +35,15 @@ abstract class ShuffleSuite extends FunSuite with Matchers with LocalSparkContex
   conf.set("spark.test.noStageRetry", "true")
 
   test("groupByKey without compression") {
-    try {
-      System.setProperty("spark.shuffle.compress", "false")
-      sc = new SparkContext("local", "test", conf)
-      val pairs = sc.parallelize(Array((1, 1), (1, 2), (1, 3), (2, 1)), 4)
-      val groups = pairs.groupByKey(4).collect()
-      assert(groups.size === 2)
-      val valuesFor1 = groups.find(_._1 == 1).get._2
-      assert(valuesFor1.toList.sorted === List(1, 2, 3))
-      val valuesFor2 = groups.find(_._1 == 2).get._2
-      assert(valuesFor2.toList.sorted === List(1))
-    } finally {
-      System.setProperty("spark.shuffle.compress", "true")
-    }
+    val myConf = conf.clone().set("spark.shuffle.compress", "false")
+    sc = new SparkContext("local", "test", myConf)
+    val pairs = sc.parallelize(Array((1, 1), (1, 2), (1, 3), (2, 1)), 4)
+    val groups = pairs.groupByKey(4).collect()
+    assert(groups.size === 2)
+    val valuesFor1 = groups.find(_._1 == 1).get._2
+    assert(valuesFor1.toList.sorted === List(1, 2, 3))
+    val valuesFor2 = groups.find(_._1 == 2).get._2
+    assert(valuesFor2.toList.sorted === List(1))
   }
 
   test("shuffle non-zero block size") {

core/src/test/scala/org/apache/spark/SparkConfSuite.scala

@@ -19,27 +19,20 @@ package org.apache.spark
 
 import org.scalatest.FunSuite
 import org.apache.spark.serializer.{KryoRegistrator, KryoSerializer}
+import org.apache.spark.util.ResetSystemProperties
 import com.esotericsoftware.kryo.Kryo
 
-class SparkConfSuite extends FunSuite with LocalSparkContext {
+class SparkConfSuite extends FunSuite with LocalSparkContext with ResetSystemProperties {
   test("loading from system properties") {
-    try {
-      System.setProperty("spark.test.testProperty", "2")
-      val conf = new SparkConf()
-      assert(conf.get("spark.test.testProperty") === "2")
-    } finally {
-      System.clearProperty("spark.test.testProperty")
-    }
+    System.setProperty("spark.test.testProperty", "2")
+    val conf = new SparkConf()
+    assert(conf.get("spark.test.testProperty") === "2")
   }
 
   test("initializing without loading defaults") {
-    try {
-      System.setProperty("spark.test.testProperty", "2")
-      val conf = new SparkConf(false)
-      assert(!conf.contains("spark.test.testProperty"))
-    } finally {
-      System.clearProperty("spark.test.testProperty")
-    }
+    System.setProperty("spark.test.testProperty", "2")
+    val conf = new SparkConf(false)
+    assert(!conf.contains("spark.test.testProperty"))
   }
 
   test("named set methods") {
@@ -117,23 +110,17 @@ class SparkConfSuite extends FunSuite with LocalSparkContext {
 
   test("nested property names") {
     // This wasn't supported by some external conf parsing libraries
-    try {
-      System.setProperty("spark.test.a", "a")
-      System.setProperty("spark.test.a.b", "a.b")
-      System.setProperty("spark.test.a.b.c", "a.b.c")
-      val conf = new SparkConf()
-      assert(conf.get("spark.test.a") === "a")
-      assert(conf.get("spark.test.a.b") === "a.b")
-      assert(conf.get("spark.test.a.b.c") === "a.b.c")
-      conf.set("spark.test.a.b", "A.B")
-      assert(conf.get("spark.test.a") === "a")
-      assert(conf.get("spark.test.a.b") === "A.B")
-      assert(conf.get("spark.test.a.b.c") === "a.b.c")
-    } finally {
-      System.clearProperty("spark.test.a")
-      System.clearProperty("spark.test.a.b")
-      System.clearProperty("spark.test.a.b.c")
-    }
+    System.setProperty("spark.test.a", "a")
+    System.setProperty("spark.test.a.b", "a.b")
+    System.setProperty("spark.test.a.b.c", "a.b.c")
+    val conf = new SparkConf()
+    assert(conf.get("spark.test.a") === "a")
+    assert(conf.get("spark.test.a.b") === "a.b")
+    assert(conf.get("spark.test.a.b.c") === "a.b.c")
+    conf.set("spark.test.a.b", "A.B")
+    assert(conf.get("spark.test.a") === "a")
+    assert(conf.get("spark.test.a.b") === "A.B")
+    assert(conf.get("spark.test.a.b.c") === "a.b.c")
   }
 
   test("register kryo classes through registerKryoClasses") {

core/src/test/scala/org/apache/spark/SparkContextSchedulerCreationSuite.scala

@@ -27,10 +27,13 @@ import org.apache.spark.scheduler.local.LocalBackend
 class SparkContextSchedulerCreationSuite
   extends FunSuite with LocalSparkContext with PrivateMethodTester with Logging {
 
-  def createTaskScheduler(master: String): TaskSchedulerImpl = {
+  def createTaskScheduler(master: String): TaskSchedulerImpl =
+    createTaskScheduler(master, new SparkConf())
+
+  def createTaskScheduler(master: String, conf: SparkConf): TaskSchedulerImpl = {
     // Create local SparkContext to setup a SparkEnv. We don't actually want to start() the
     // real schedulers, so we don't want to create a full SparkContext with the desired scheduler.
-    sc = new SparkContext("local", "test")
+    sc = new SparkContext("local", "test", conf)
     val createTaskSchedulerMethod =
       PrivateMethod[Tuple2[SchedulerBackend, TaskScheduler]]('createTaskScheduler)
     val (_, sched) = SparkContext invokePrivate createTaskSchedulerMethod(sc, master)
@@ -102,19 +105,13 @@ class SparkContextSchedulerCreationSuite
   }
 
   test("local-default-parallelism") {
-    val defaultParallelism = System.getProperty("spark.default.parallelism")
-    System.setProperty("spark.default.parallelism", "16")
-    val sched = createTaskScheduler("local")
+    val conf = new SparkConf().set("spark.default.parallelism", "16")
+    val sched = createTaskScheduler("local", conf)
 
     sched.backend match {
       case s: LocalBackend => assert(s.defaultParallelism() === 16)
       case _ => fail()
     }
-
-    Option(defaultParallelism) match {
-      case Some(v) => System.setProperty("spark.default.parallelism", v)
-      case _ => System.clearProperty("spark.default.parallelism")
-    }
   }
 
   test("simr") {
@@ -155,9 +152,10 @@ class SparkContextSchedulerCreationSuite
     testYarn("yarn-client", "org.apache.spark.scheduler.cluster.YarnClientClusterScheduler")
   }
 
-  def testMesos(master: String, expectedClass: Class[_]) {
+  def testMesos(master: String, expectedClass: Class[_], coarse: Boolean) {
+    val conf = new SparkConf().set("spark.mesos.coarse", coarse.toString)
     try {
-      val sched = createTaskScheduler(master)
+      val sched = createTaskScheduler(master, conf)
       assert(sched.backend.getClass === expectedClass)
     } catch {
       case e: UnsatisfiedLinkError =>
@@ -168,17 +166,14 @@ class SparkContextSchedulerCreationSuite
   }
 
   test("mesos fine-grained") {
-    System.setProperty("spark.mesos.coarse", "false")
-    testMesos("mesos://localhost:1234", classOf[MesosSchedulerBackend])
+    testMesos("mesos://localhost:1234", classOf[MesosSchedulerBackend], coarse = false)
   }
 
   test("mesos coarse-grained") {
-    System.setProperty("spark.mesos.coarse", "true")
-    testMesos("mesos://localhost:1234", classOf[CoarseMesosSchedulerBackend])
+    testMesos("mesos://localhost:1234", classOf[CoarseMesosSchedulerBackend], coarse = true)
   }
 
   test("mesos with zookeeper") {
-    System.setProperty("spark.mesos.coarse", "false")
-    testMesos("zk://localhost:1234,localhost:2345", classOf[MesosSchedulerBackend])
+    testMesos("zk://localhost:1234,localhost:2345", classOf[MesosSchedulerBackend], coarse = false)
   }
 }