Implemented persistent transactional queue with Redis backend

akka-persistence/akka-persistence-redis/src/test/scala/RedisPersistentQSpec.scala

@@ -0,0 +1,133 @@
+package se.scalablesolutions.akka.state
+
+import junit.framework.TestCase
+
+import org.junit.{Test, Before}
+import org.junit.Assert._
+
+import se.scalablesolutions.akka.actor.{Actor, Transactor}
+
+/**
+ * A persistent actor based on Redis queue storage.
+ * <p/>
+ * Needs a running Redis server.
+ * @author <a href="http://debasishg.blogspot.com">Debasish Ghosh</a>
+ */
+
+case class NQ(accountNo: String)
+case class DQ
+case class MNDQ(accountNos: List[String], noOfDQs: Int, failer: Actor)
+case class SZ
+
+class QueueActor extends Transactor {
+  private val accounts = RedisStorage.newQueue
+
+  def receive = {
+    // enqueue
+    case NQ(accountNo) =>
+      accounts.enqueue(accountNo.getBytes)
+      reply(true)
+
+    // dequeue
+    case DQ =>
+      val d = new String(accounts.dequeue)
+      reply(d)
+
+    // multiple NQ and DQ
+    case MNDQ(enqs, no, failer) =>
+      accounts.enqueue(enqs.map(_.getBytes): _*)
+      try {
+        (1 to no).foreach(e => accounts.dequeue)
+      } catch {
+        case e: Exception => 
+          failer !! "Failure"
+      }
+      reply(true)
+
+    // size
+    case SZ =>
+      reply(accounts.size)
+  }
+}
+
+class RedisPersistentQSpec extends TestCase {
+  @Test
+  def testSuccessfulNQ = {
+    val qa = new QueueActor
+    qa.start
+    qa !! NQ("a-123")
+    qa !! NQ("a-124")
+    qa !! NQ("a-125")
+    assertEquals(3, (qa !! SZ).get)
+  }
+
+  @Test
+  def testSuccessfulDQ = {
+    val qa = new QueueActor
+    qa.start
+    qa !! NQ("a-123")
+    qa !! NQ("a-124")
+    qa !! NQ("a-125")
+    assertEquals(3, (qa !! SZ).get)
+    assertEquals("a-123", (qa !! DQ).get)
+    assertEquals("a-124", (qa !! DQ).get)
+    assertEquals("a-125", (qa !! DQ).get)
+    assertEquals(0, (qa !! SZ).get)
+  }
+
+  @Test
+  def testSuccessfulMNDQ = {
+    val qa = new QueueActor
+    qa.start
+    val failer = new PersistentFailerActor
+    failer.start
+
+    qa !! NQ("a-123")
+    qa !! NQ("a-124")
+    qa !! NQ("a-125")
+    assertEquals(3, (qa !! SZ).get)
+    assertEquals("a-123", (qa !! DQ).get)
+    assertEquals(2, (qa !! SZ).get)
+    qa !! MNDQ(List("a-126", "a-127"), 2, failer)
+    assertEquals(2, (qa !! SZ).get)
+  }
+
+  @Test
+  def testMixedMNDQ = {
+    val qa = new QueueActor
+    qa.start
+    val failer = new PersistentFailerActor
+    failer.start
+
+    // 3 enqueues
+    qa !! NQ("a-123")
+    qa !! NQ("a-124")
+    qa !! NQ("a-125")
+
+    assertEquals(3, (qa !! SZ).get)
+
+    // dequeue 1
+    assertEquals("a-123", (qa !! DQ).get)
+
+    // size == 2
+    assertEquals(2, (qa !! SZ).get)
+
+    // enqueue 2, dequeue 2 => size == 2
+    qa !! MNDQ(List("a-126", "a-127"), 2, failer)
+    assertEquals(2, (qa !! SZ).get)
+
+    // enqueue 2 => size == 4
+    qa !! NQ("a-128")
+    qa !! NQ("a-129")
+    assertEquals(4, (qa !! SZ).get)
+
+    // enqueue 1 => size 5
+    // dequeue 6 => fail transaction
+    // size should remain 4
+    try {
+      qa !! MNDQ(List("a-130"), 6, failer)
+    } catch { case e: Exception => {} }
+
+    assertEquals(4, (qa !! SZ).get)
+  }
+}