Add log size to SiriusPersistenceActor

* accessable via a message to the actor
* also will be visible via jmx and in the sirius
  status

Author: kristomasette

src/main/scala/com/comcast/xfinity/sirius/api/impl/state/SiriusPersistenceActor.scala

@@ -30,6 +30,7 @@ object SiriusPersistenceActor {
    */
   sealed trait LogQuery
 
+  case object GetLogSize extends LogQuery
   /**
    * Message for directly requesting a chunk of the log from a node.
    *
@@ -151,6 +152,9 @@ class SiriusPersistenceActor(stateActor: ActorRef,
     case GetNextLogSeq =>
       sender ! siriusLog.getNextSeq
 
+    case GetLogSize =>
+      sender ! siriusLog.size
+
     // XXX SiriusStateActor responds to writes with a SiriusResult, we don't really want this
     // anymore, and it should be eliminated in a future commit
     case _: SiriusResult =>
@@ -161,12 +165,12 @@ class SiriusPersistenceActor(stateActor: ActorRef,
    */
   trait SiriusPersistenceActorInfoMBean {
     def getAveragePersistDuration: Double
+    def getSiriusLogSize: Long
   }
 
   class SiriusPersistenceActorInfo extends SiriusPersistenceActorInfoMBean {
 
-
-
     def getAveragePersistDuration = cummWeightedAvg
+    def getSiriusLogSize = siriusLog.size
   }
 }

src/test/scala/com/comcast/xfinity/sirius/api/impl/state/SiriusPersistenceActorTest.scala

@@ -53,6 +53,14 @@ class SiriusPersistenceActorTest extends NiceTest {
 
     //TODO: Should have tests for calls to mockSiriusLog
 
+    it("should report log size"){
+      when(mockSiriusLog.size).thenReturn(500L);
+
+      val senderProbe = TestProbe()(actorSystem)
+      senderProbe.send(underTestActor, GetLogSize)
+      senderProbe.expectMsg(500L)
+    }
+
     it ("should forward Put's to the state actor") {
       when(mockSiriusLog.getNextSeq).thenReturn(0)