[SPARK-7436] Fixed instantiation of custom recovery mode factory and added tests

Author: Jacek Lewandowski <lewandowski.jacek@gmail.com>

Closes #5977 from jacek-lewandowski/SPARK-7436 and squashes the following commits:

ff0a3c2 [Jacek Lewandowski] SPARK-7436: Fixed instantiation of custom recovery mode factory and added tests

core/src/main/scala/org/apache/spark/deploy/master/Master.scala

@@ -165,7 +165,7 @@ private[master] class Master(
         (fsFactory.createPersistenceEngine(), fsFactory.createLeaderElectionAgent(this))
       case "CUSTOM" =>
         val clazz = Class.forName(conf.get("spark.deploy.recoveryMode.factory"))
-        val factory = clazz.getConstructor(conf.getClass, Serialization.getClass)
+        val factory = clazz.getConstructor(classOf[SparkConf], classOf[Serialization])
           .newInstance(conf, SerializationExtension(context.system))
           .asInstanceOf[StandaloneRecoveryModeFactory]
         (factory.createPersistenceEngine(), factory.createLeaderElectionAgent(this))

core/src/test/scala/org/apache/spark/deploy/master/CustomRecoveryModeFactory.scala

+/*
+ * 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.
+ */
+
+// This file is placed in different package to make sure all of these components work well
+// when they are outside of org.apache.spark.
+package other.supplier
+
+import scala.collection.mutable
+import scala.reflect.ClassTag
+
+import akka.serialization.Serialization
+
+import org.apache.spark.SparkConf
+import org.apache.spark.deploy.master._
+
+class CustomRecoveryModeFactory(
+  conf: SparkConf,
+  serialization: Serialization
+) extends StandaloneRecoveryModeFactory(conf, serialization) {
+
+  CustomRecoveryModeFactory.instantiationAttempts += 1
+
+  /**
+   * PersistenceEngine defines how the persistent data(Information about worker, driver etc..)
+   * is handled for recovery.
+   *
+   */
+  override def createPersistenceEngine(): PersistenceEngine =
+    new CustomPersistenceEngine(serialization)
+
+  /**
+   * Create an instance of LeaderAgent that decides who gets elected as master.
+   */
+  override def createLeaderElectionAgent(master: LeaderElectable): LeaderElectionAgent =
+    new CustomLeaderElectionAgent(master)
+}
+
+object CustomRecoveryModeFactory {
+  @volatile var instantiationAttempts = 0
+}
+
+class CustomPersistenceEngine(serialization: Serialization) extends PersistenceEngine {
+  val data = mutable.HashMap[String, Array[Byte]]()
+
+  CustomPersistenceEngine.lastInstance = Some(this)
+
+  /**
+   * Defines how the object is serialized and persisted. Implementation will
+   * depend on the store used.
+   */
+  override def persist(name: String, obj: Object): Unit = {
+    CustomPersistenceEngine.persistAttempts += 1
+    serialization.serialize(obj) match {
+      case util.Success(bytes) => data += name -> bytes
+      case util.Failure(cause) => throw new RuntimeException(cause)
+    }
+  }
+
+  /**
+   * Defines how the object referred by its name is removed from the store.
+   */
+  override def unpersist(name: String): Unit = {
+    CustomPersistenceEngine.unpersistAttempts += 1
+    data -= name
+  }
+
+  /**
+   * Gives all objects, matching a prefix. This defines how objects are
+   * read/deserialized back.
+   */
+  override def read[T: ClassTag](prefix: String): Seq[T] = {
+    CustomPersistenceEngine.readAttempts += 1
+    val clazz = implicitly[ClassTag[T]].runtimeClass.asInstanceOf[Class[T]]
+    val results = for ((name, bytes) <- data; if name.startsWith(prefix))
+      yield serialization.deserialize(bytes, clazz)
+
+    results.find(_.isFailure).foreach {
+      case util.Failure(cause) => throw new RuntimeException(cause)
+    }
+
+    results.flatMap(_.toOption).toSeq
+  }
+}
+
+object CustomPersistenceEngine {
+  @volatile var persistAttempts = 0
+  @volatile var unpersistAttempts = 0
+  @volatile var readAttempts = 0
+
+  @volatile var lastInstance: Option[CustomPersistenceEngine] = None
+}
+
+class CustomLeaderElectionAgent(val masterActor: LeaderElectable) extends LeaderElectionAgent {
+  masterActor.electedLeader()
+}
+

core/src/test/scala/org/apache/spark/deploy/master/MasterSuite.scala

@@ -17,12 +17,20 @@
 
 package org.apache.spark.deploy.master
 
+import java.util.Date
+
+import scala.concurrent.Await
+import scala.concurrent.duration._
+import scala.language.postfixOps
+
 import akka.actor.Address
-import org.scalatest.FunSuite
+import org.scalatest.{FunSuite, Matchers}
+import other.supplier.{CustomPersistenceEngine, CustomRecoveryModeFactory}
 
-import org.apache.spark.{SSLOptions, SparkConf, SparkException}
+import org.apache.spark.deploy._
+import org.apache.spark.{SparkConf, SparkException}
 
-class MasterSuite extends FunSuite {
+class MasterSuite extends FunSuite with Matchers {
 
   test("toAkkaUrl") {
     val conf = new SparkConf(loadDefaults = false)
@@ -63,4 +71,90 @@ class MasterSuite extends FunSuite {
     }
     assert("Invalid master URL: spark://1.2. 3.4:1234" === e.getMessage)
   }
+
+  test("can use a custom recovery mode factory") {
+    val conf = new SparkConf(loadDefaults = false)
+    conf.set("spark.deploy.recoveryMode", "CUSTOM")
+    conf.set("spark.deploy.recoveryMode.factory",
+      classOf[CustomRecoveryModeFactory].getCanonicalName)
+
+    val instantiationAttempts = CustomRecoveryModeFactory.instantiationAttempts
+
+    val commandToPersist = new Command(
+      mainClass = "",
+      arguments = Nil,
+      environment = Map.empty,
+      classPathEntries = Nil,
+      libraryPathEntries = Nil,
+      javaOpts = Nil
+    )
+
+    val appToPersist = new ApplicationInfo(
+      startTime = 0,
+      id = "test_app",
+      desc = new ApplicationDescription(
+        name = "",
+        maxCores = None,
+        memoryPerExecutorMB = 0,
+        command = commandToPersist,
+        appUiUrl = "",
+        eventLogDir = None,
+        eventLogCodec = None,
+        coresPerExecutor = None),
+      submitDate = new Date(),
+      driver = null,
+      defaultCores = 0
+    )
+
+    val driverToPersist = new DriverInfo(
+      startTime = 0,
+      id = "test_driver",
+      desc = new DriverDescription(
+        jarUrl = "",
+        mem = 0,
+        cores = 0,
+        supervise = false,
+        command = commandToPersist
+      ),
+      submitDate = new Date()
+    )
+
+    val workerToPersist = new WorkerInfo(
+      id = "test_worker",
+      host = "127.0.0.1",
+      port = 10000,
+      cores = 0,
+      memory = 0,
+      actor = null,
+      webUiPort = 0,
+      publicAddress = ""
+    )
+
+    val (actorSystem, port, uiPort, restPort) =
+      Master.startSystemAndActor("127.0.0.1", 7077, 8080, conf)
+
+    try {
+      Await.result(actorSystem.actorSelection("/user/Master").resolveOne(10 seconds), 10 seconds)
+
+      CustomPersistenceEngine.lastInstance.isDefined shouldBe true
+      val persistenceEngine = CustomPersistenceEngine.lastInstance.get
+
+      persistenceEngine.addApplication(appToPersist)
+      persistenceEngine.addDriver(driverToPersist)
+      persistenceEngine.addWorker(workerToPersist)
+
+      val (apps, drivers, workers) = persistenceEngine.readPersistedData()
+
+      apps.map(_.id) should contain(appToPersist.id)
+      drivers.map(_.id) should contain(driverToPersist.id)
+      workers.map(_.id) should contain(workerToPersist.id)
+
+    } finally {
+      actorSystem.shutdown()
+      actorSystem.awaitTermination()
+    }
+
+    CustomRecoveryModeFactory.instantiationAttempts should be > instantiationAttempts
+  }
+
 }