Fix license header violations in sal-akka-raft
[controller.git] / opendaylight / md-sal / sal-akka-raft / src / test / java / org / opendaylight / controller / cluster / raft / RaftActorTest.java
index 56bfc21f23c2047a19d5a49c49861ae1bf6eca5e..047bac91fdceeaf9102a3b909d5da00b54772345 100644 (file)
@@ -1,43 +1,41 @@
+/*
+ * Copyright (c) 2014, 2015 Cisco Systems, Inc. and others.  All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v1.0 which accompanies this distribution,
+ * and is available at http://www.eclipse.org/legal/epl-v10.html
+ */
+
 package org.opendaylight.controller.cluster.raft;
 
 import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertNotEquals;
 import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
 import static org.mockito.Matchers.any;
 import static org.mockito.Matchers.anyObject;
 import static org.mockito.Matchers.eq;
+import static org.mockito.Matchers.same;
 import static org.mockito.Mockito.doReturn;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
 import akka.actor.ActorRef;
-import akka.actor.ActorSystem;
 import akka.actor.PoisonPill;
 import akka.actor.Props;
 import akka.actor.Terminated;
-import akka.japi.Creator;
 import akka.japi.Procedure;
-import akka.pattern.Patterns;
-import akka.persistence.RecoveryCompleted;
 import akka.persistence.SaveSnapshotFailure;
 import akka.persistence.SaveSnapshotSuccess;
 import akka.persistence.SnapshotMetadata;
 import akka.persistence.SnapshotOffer;
-import akka.persistence.SnapshotSelectionCriteria;
 import akka.testkit.JavaTestKit;
 import akka.testkit.TestActorRef;
-import akka.util.Timeout;
 import com.google.common.base.Optional;
-import com.google.common.collect.Lists;
+import com.google.common.collect.ImmutableMap;
 import com.google.common.util.concurrent.Uninterruptibles;
 import com.google.protobuf.ByteString;
-import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
-import java.io.IOException;
-import java.io.ObjectInputStream;
 import java.io.ObjectOutputStream;
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -45,39 +43,39 @@ import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
-import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeUnit;
-import java.util.concurrent.TimeoutException;
 import org.junit.After;
-import org.junit.Assert;
 import org.junit.Before;
 import org.junit.Test;
 import org.opendaylight.controller.cluster.DataPersistenceProvider;
-import org.opendaylight.controller.cluster.datastore.DataPersistenceProviderMonitor;
+import org.opendaylight.controller.cluster.NonPersistentDataProvider;
+import org.opendaylight.controller.cluster.notifications.LeaderStateChanged;
 import org.opendaylight.controller.cluster.notifications.RoleChanged;
+import org.opendaylight.controller.cluster.raft.base.messages.ApplyJournalEntries;
 import org.opendaylight.controller.cluster.raft.base.messages.ApplyLogEntries;
 import org.opendaylight.controller.cluster.raft.base.messages.ApplySnapshot;
 import org.opendaylight.controller.cluster.raft.base.messages.ApplyState;
 import org.opendaylight.controller.cluster.raft.base.messages.CaptureSnapshot;
 import org.opendaylight.controller.cluster.raft.base.messages.CaptureSnapshotReply;
+import org.opendaylight.controller.cluster.raft.base.messages.DeleteEntries;
 import org.opendaylight.controller.cluster.raft.base.messages.SendHeartBeat;
+import org.opendaylight.controller.cluster.raft.base.messages.UpdateElectionTerm;
 import org.opendaylight.controller.cluster.raft.behaviors.Follower;
 import org.opendaylight.controller.cluster.raft.behaviors.Leader;
-import org.opendaylight.controller.cluster.raft.client.messages.FindLeader;
-import org.opendaylight.controller.cluster.raft.client.messages.FindLeaderReply;
+import org.opendaylight.controller.cluster.raft.behaviors.RaftActorBehavior;
 import org.opendaylight.controller.cluster.raft.messages.AppendEntries;
 import org.opendaylight.controller.cluster.raft.messages.AppendEntriesReply;
-import org.opendaylight.controller.cluster.raft.protobuff.client.messages.Payload;
+import org.opendaylight.controller.cluster.raft.utils.InMemoryJournal;
+import org.opendaylight.controller.cluster.raft.utils.InMemorySnapshotStore;
 import org.opendaylight.controller.cluster.raft.utils.MessageCollectorActor;
-import org.opendaylight.controller.cluster.raft.utils.MockAkkaJournal;
-import org.opendaylight.controller.cluster.raft.utils.MockSnapshotStore;
-import scala.concurrent.Await;
-import scala.concurrent.Future;
-import scala.concurrent.duration.Duration;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import scala.concurrent.duration.FiniteDuration;
 
 public class RaftActorTest extends AbstractActorTest {
 
+    static final Logger TEST_LOG = LoggerFactory.getLogger(RaftActorTest.class);
+
     private TestActorFactory factory;
 
     @Before
@@ -88,249 +86,10 @@ public class RaftActorTest extends AbstractActorTest {
     @After
     public void tearDown() throws Exception {
         factory.close();
-        MockAkkaJournal.clearJournal();
-        MockSnapshotStore.setMockSnapshot(null);
-    }
-
-    public static class MockRaftActor extends RaftActor {
-
-        private final DataPersistenceProvider dataPersistenceProvider;
-        private final RaftActor delegate;
-        private final CountDownLatch recoveryComplete = new CountDownLatch(1);
-        private final List<Object> state;
-        private ActorRef roleChangeNotifier;
-        private final CountDownLatch initializeBehaviorComplete = new CountDownLatch(1);
-
-        public static final class MockRaftActorCreator implements Creator<MockRaftActor> {
-            private static final long serialVersionUID = 1L;
-            private final Map<String, String> peerAddresses;
-            private final String id;
-            private final Optional<ConfigParams> config;
-            private final DataPersistenceProvider dataPersistenceProvider;
-            private final ActorRef roleChangeNotifier;
-
-            private MockRaftActorCreator(Map<String, String> peerAddresses, String id,
-                Optional<ConfigParams> config, DataPersistenceProvider dataPersistenceProvider,
-                ActorRef roleChangeNotifier) {
-                this.peerAddresses = peerAddresses;
-                this.id = id;
-                this.config = config;
-                this.dataPersistenceProvider = dataPersistenceProvider;
-                this.roleChangeNotifier = roleChangeNotifier;
-            }
-
-            @Override
-            public MockRaftActor create() throws Exception {
-                MockRaftActor mockRaftActor = new MockRaftActor(id, peerAddresses, config,
-                    dataPersistenceProvider);
-                mockRaftActor.roleChangeNotifier = this.roleChangeNotifier;
-                return mockRaftActor;
-            }
-        }
-
-        public MockRaftActor(String id, Map<String, String> peerAddresses, Optional<ConfigParams> config,
-                             DataPersistenceProvider dataPersistenceProvider) {
-            super(id, peerAddresses, config);
-            state = new ArrayList<>();
-            this.delegate = mock(RaftActor.class);
-            if(dataPersistenceProvider == null){
-                this.dataPersistenceProvider = new PersistentDataProvider();
-            } else {
-                this.dataPersistenceProvider = dataPersistenceProvider;
-            }
-        }
-
-        public void waitForRecoveryComplete() {
-            try {
-                assertEquals("Recovery complete", true, recoveryComplete.await(5,  TimeUnit.SECONDS));
-            } catch (InterruptedException e) {
-                e.printStackTrace();
-            }
-        }
-
-        public void waitForInitializeBehaviorComplete() {
-            try {
-                assertEquals("Behavior initialized", true, initializeBehaviorComplete.await(5,  TimeUnit.SECONDS));
-            } catch (InterruptedException e) {
-                e.printStackTrace();
-            }
-        }
-
-        public List<Object> getState() {
-            return state;
-        }
-
-        public static Props props(final String id, final Map<String, String> peerAddresses,
-                Optional<ConfigParams> config){
-            return Props.create(new MockRaftActorCreator(peerAddresses, id, config, null, null));
-        }
-
-        public static Props props(final String id, final Map<String, String> peerAddresses,
-                                  Optional<ConfigParams> config, DataPersistenceProvider dataPersistenceProvider){
-            return Props.create(new MockRaftActorCreator(peerAddresses, id, config, dataPersistenceProvider, null));
-        }
-
-        public static Props props(final String id, final Map<String, String> peerAddresses,
-            Optional<ConfigParams> config, ActorRef roleChangeNotifier){
-            return Props.create(new MockRaftActorCreator(peerAddresses, id, config, null, roleChangeNotifier));
-        }
-
-        @Override protected void applyState(ActorRef clientActor, String identifier, Object data) {
-            delegate.applyState(clientActor, identifier, data);
-            LOG.info("applyState called");
-        }
-
-        @Override
-        protected void startLogRecoveryBatch(int maxBatchSize) {
-        }
-
-        @Override
-        protected void appendRecoveredLogEntry(Payload data) {
-            state.add(data);
-        }
-
-        @Override
-        protected void applyCurrentLogRecoveryBatch() {
-        }
-
-        @Override
-        protected void onRecoveryComplete() {
-            delegate.onRecoveryComplete();
-            recoveryComplete.countDown();
-        }
-
-        @Override
-        protected void initializeBehavior() {
-            super.initializeBehavior();
-            initializeBehaviorComplete.countDown();
-        }
-
-        @Override
-        protected void applyRecoverySnapshot(byte[] bytes) {
-            delegate.applyRecoverySnapshot(bytes);
-            try {
-                Object data = toObject(bytes);
-                if (data instanceof List) {
-                    state.addAll((List<?>) data);
-                }
-            } catch (Exception e) {
-                e.printStackTrace();
-            }
-        }
-
-        @Override protected void createSnapshot() {
-            delegate.createSnapshot();
-        }
-
-        @Override protected void applySnapshot(byte [] snapshot) {
-            delegate.applySnapshot(snapshot);
-        }
-
-        @Override protected void onStateChanged() {
-            delegate.onStateChanged();
-        }
-
-        @Override
-        protected DataPersistenceProvider persistence() {
-            return this.dataPersistenceProvider;
-        }
-
-        @Override
-        protected Optional<ActorRef> getRoleChangeNotifier() {
-            return Optional.fromNullable(roleChangeNotifier);
-        }
-
-        @Override public String persistenceId() {
-            return this.getId();
-        }
-
-        private Object toObject(byte[] bs) throws ClassNotFoundException, IOException {
-            Object obj = null;
-            ByteArrayInputStream bis = null;
-            ObjectInputStream ois = null;
-            try {
-                bis = new ByteArrayInputStream(bs);
-                ois = new ObjectInputStream(bis);
-                obj = ois.readObject();
-            } finally {
-                if (bis != null) {
-                    bis.close();
-                }
-                if (ois != null) {
-                    ois.close();
-                }
-            }
-            return obj;
-        }
-
-        public ReplicatedLog getReplicatedLog(){
-            return this.getRaftActorContext().getReplicatedLog();
-        }
-
-    }
-
-
-    private static class RaftActorTestKit extends JavaTestKit {
-        private final ActorRef raftActor;
-
-        public RaftActorTestKit(ActorSystem actorSystem, String actorName) {
-            super(actorSystem);
-
-            raftActor = this.getSystem().actorOf(MockRaftActor.props(actorName,
-                    Collections.<String,String>emptyMap(), Optional.<ConfigParams>absent()), actorName);
-
-        }
-
-
-        public ActorRef getRaftActor() {
-            return raftActor;
-        }
-
-        public boolean waitForLogMessage(final Class<?> logEventClass, String message){
-            // Wait for a specific log message to show up
-            return
-                new JavaTestKit.EventFilter<Boolean>(logEventClass
-                ) {
-                    @Override
-                    protected Boolean run() {
-                        return true;
-                    }
-                }.from(raftActor.path().toString())
-                    .message(message)
-                    .occurrences(1).exec();
-
-
-        }
-
-        protected void waitUntilLeader(){
-            waitUntilLeader(raftActor);
-        }
-
-        protected void waitUntilLeader(ActorRef actorRef) {
-            FiniteDuration duration = Duration.create(100, TimeUnit.MILLISECONDS);
-            for(int i = 0; i < 20 * 5; i++) {
-                Future<Object> future = Patterns.ask(actorRef, new FindLeader(), new Timeout(duration));
-                try {
-                    FindLeaderReply resp = (FindLeaderReply) Await.result(future, duration);
-                    if(resp.getLeaderActor() != null) {
-                        return;
-                    }
-                } catch(TimeoutException e) {
-                } catch(Exception e) {
-                    System.err.println("FindLeader threw ex");
-                    e.printStackTrace();
-                }
-
-
-                Uninterruptibles.sleepUninterruptibly(50, TimeUnit.MILLISECONDS);
-            }
-
-            Assert.fail("Leader not found for actorRef " + actorRef.path());
-        }
-
+        InMemoryJournal.clear();
+        InMemorySnapshotStore.clear();
     }
 
-
     @Test
     public void testConstruction() {
         new RaftActorTestKit(getSystem(), "testConstruction").waitUntilLeader();
@@ -343,18 +102,22 @@ public class RaftActorTest extends AbstractActorTest {
     }
 
     @Test
-    public void testRaftActorRecovery() throws Exception {
+    public void testRaftActorRecoveryWithPersistenceEnabled() throws Exception {
+        TEST_LOG.info("testRaftActorRecoveryWithPersistenceEnabled starting");
+
         new JavaTestKit(getSystem()) {{
             String persistenceId = factory.generateActorId("follower-");
 
             DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
+
             // Set the heartbeat interval high to essentially disable election otherwise the test
             // may fail if the actor is switched to Leader and the commitIndex is set to the last
             // log entry.
             config.setHeartBeatInterval(new FiniteDuration(1, TimeUnit.DAYS));
 
+            ImmutableMap<String, String> peerAddresses = ImmutableMap.<String, String>builder().put("member1", "address").build();
             ActorRef followerActor = factory.createActor(MockRaftActor.props(persistenceId,
-                    Collections.<String, String>emptyMap(), Optional.<ConfigParams>of(config)), persistenceId);
+                    peerAddresses, Optional.<ConfigParams>of(config)), persistenceId);
 
             watch(followerActor);
 
@@ -376,17 +139,16 @@ public class RaftActorTest extends AbstractActorTest {
             Snapshot snapshot = Snapshot.create(snapshotBytes.toByteArray(),
                     snapshotUnappliedEntries, lastIndexDuringSnapshotCapture, 1,
                     lastAppliedDuringSnapshotCapture, 1);
-            MockSnapshotStore.setMockSnapshot(snapshot);
-            MockSnapshotStore.setPersistenceId(persistenceId);
+            InMemorySnapshotStore.addSnapshot(persistenceId, snapshot);
 
             // add more entries after snapshot is taken
             List<ReplicatedLogEntry> entries = new ArrayList<>();
             ReplicatedLogEntry entry2 = new MockRaftActorContext.MockReplicatedLogEntry(1, 5,
-                    new MockRaftActorContext.MockPayload("F"));
+                    new MockRaftActorContext.MockPayload("F", 2));
             ReplicatedLogEntry entry3 = new MockRaftActorContext.MockReplicatedLogEntry(1, 6,
-                    new MockRaftActorContext.MockPayload("G"));
+                    new MockRaftActorContext.MockPayload("G", 3));
             ReplicatedLogEntry entry4 = new MockRaftActorContext.MockReplicatedLogEntry(1, 7,
-                    new MockRaftActorContext.MockPayload("H"));
+                    new MockRaftActorContext.MockPayload("H", 4));
             entries.add(entry2);
             entries.add(entry3);
             entries.add(entry4);
@@ -394,11 +156,11 @@ public class RaftActorTest extends AbstractActorTest {
             int lastAppliedToState = 5;
             int lastIndex = 7;
 
-            MockAkkaJournal.addToJournal(5, entry2);
+            InMemoryJournal.addEntry(persistenceId, 5, entry2);
             // 2 entries are applied to state besides the 4 entries in snapshot
-            MockAkkaJournal.addToJournal(6, new ApplyLogEntries(lastAppliedToState));
-            MockAkkaJournal.addToJournal(7, entry3);
-            MockAkkaJournal.addToJournal(8, entry4);
+            InMemoryJournal.addEntry(persistenceId, 6, new ApplyJournalEntries(lastAppliedToState));
+            InMemoryJournal.addEntry(persistenceId, 7, entry3);
+            InMemoryJournal.addEntry(persistenceId, 8, entry4);
 
             // kill the actor
             followerActor.tell(PoisonPill.getInstance(), null);
@@ -408,308 +170,160 @@ public class RaftActorTest extends AbstractActorTest {
 
             //reinstate the actor
             TestActorRef<MockRaftActor> ref = factory.createTestActor(
-                    MockRaftActor.props(persistenceId, Collections.<String, String>emptyMap(),
-                            Optional.<ConfigParams>of(config)));
+                    MockRaftActor.props(persistenceId, peerAddresses, Optional.<ConfigParams>of(config)));
 
-            ref.underlyingActor().waitForRecoveryComplete();
+            MockRaftActor mockRaftActor = ref.underlyingActor();
 
-            RaftActorContext context = ref.underlyingActor().getRaftActorContext();
+            mockRaftActor.waitForRecoveryComplete();
+
+            RaftActorContext context = mockRaftActor.getRaftActorContext();
             assertEquals("Journal log size", snapshotUnappliedEntries.size() + entries.size(),
                     context.getReplicatedLog().size());
+            assertEquals("Journal data size", 10, context.getReplicatedLog().dataSize());
             assertEquals("Last index", lastIndex, context.getReplicatedLog().lastIndex());
             assertEquals("Last applied", lastAppliedToState, context.getLastApplied());
             assertEquals("Commit index", lastAppliedToState, context.getCommitIndex());
-            assertEquals("Recovered state size", 6, ref.underlyingActor().getState().size());
-        }};
-    }
-
-    /**
-     * This test verifies that when recovery is applicable (typically when persistence is true) the RaftActor does
-     * process recovery messages
-     *
-     * @throws Exception
-     */
-
-    @Test
-    public void testHandleRecoveryWhenDataPersistenceRecoveryApplicable() throws Exception {
-        new JavaTestKit(getSystem()) {
-            {
-                String persistenceId = factory.generateActorId("leader-");
-
-                DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
-
-                config.setHeartBeatInterval(new FiniteDuration(1, TimeUnit.DAYS));
-
-                TestActorRef<MockRaftActor> mockActorRef = factory.createTestActor(MockRaftActor.props(persistenceId,
-                        Collections.<String, String>emptyMap(), Optional.<ConfigParams>of(config)), persistenceId);
-
-                MockRaftActor mockRaftActor = mockActorRef.underlyingActor();
-
-                // Wait for akka's recovery to complete so it doesn't interfere.
-                mockRaftActor.waitForRecoveryComplete();
-
-                ByteString snapshotBytes = fromObject(Arrays.asList(
-                        new MockRaftActorContext.MockPayload("A"),
-                        new MockRaftActorContext.MockPayload("B"),
-                        new MockRaftActorContext.MockPayload("C"),
-                        new MockRaftActorContext.MockPayload("D")));
-
-                Snapshot snapshot = Snapshot.create(snapshotBytes.toByteArray(),
-                        Lists.<ReplicatedLogEntry>newArrayList(), 3, 1, 3, 1);
-
-                mockRaftActor.onReceiveRecover(new SnapshotOffer(new SnapshotMetadata(persistenceId, 100, 100), snapshot));
-
-                verify(mockRaftActor.delegate).applyRecoverySnapshot(eq(snapshotBytes.toByteArray()));
-
-                mockRaftActor.onReceiveRecover(new ReplicatedLogImplEntry(0, 1, new MockRaftActorContext.MockPayload("A")));
-
-                ReplicatedLog replicatedLog = mockRaftActor.getReplicatedLog();
-
-                assertEquals("add replicated log entry", 1, replicatedLog.size());
-
-                mockRaftActor.onReceiveRecover(new ReplicatedLogImplEntry(1, 1, new MockRaftActorContext.MockPayload("A")));
-
-                assertEquals("add replicated log entry", 2, replicatedLog.size());
-
-                mockRaftActor.onReceiveRecover(new ApplyLogEntries(1));
-
-                assertEquals("commit index 1", 1, mockRaftActor.getRaftActorContext().getCommitIndex());
-
-                // The snapshot had 4 items + we added 2 more items during the test
-                // We start removing from 5 and we should get 1 item in the replicated log
-                mockRaftActor.onReceiveRecover(new RaftActor.DeleteEntries(5));
-
-                assertEquals("remove log entries", 1, replicatedLog.size());
-
-                mockRaftActor.onReceiveRecover(new RaftActor.UpdateElectionTerm(10, "foobar"));
-
-                assertEquals("election term", 10, mockRaftActor.getRaftActorContext().getTermInformation().getCurrentTerm());
-                assertEquals("voted for", "foobar", mockRaftActor.getRaftActorContext().getTermInformation().getVotedFor());
-
-                mockRaftActor.onReceiveRecover(mock(RecoveryCompleted.class));
-
-            }};
-    }
-
-    /**
-     * This test verifies that when recovery is not applicable (typically when persistence is false) the RaftActor does
-     * not process recovery messages
-     *
-     * @throws Exception
-     */
-    @Test
-    public void testHandleRecoveryWhenDataPersistenceRecoveryNotApplicable() throws Exception {
-        new JavaTestKit(getSystem()) {
-            {
-                String persistenceId = factory.generateActorId("leader-");
-
-                DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
-
-                config.setHeartBeatInterval(new FiniteDuration(1, TimeUnit.DAYS));
-
-                TestActorRef<MockRaftActor> mockActorRef = factory.createTestActor(MockRaftActor.props(persistenceId,
-                        Collections.<String, String>emptyMap(), Optional.<ConfigParams>of(config), new DataPersistenceProviderMonitor()), persistenceId);
-
-                MockRaftActor mockRaftActor = mockActorRef.underlyingActor();
-
-                // Wait for akka's recovery to complete so it doesn't interfere.
-                mockRaftActor.waitForRecoveryComplete();
-
-                ByteString snapshotBytes = fromObject(Arrays.asList(
-                        new MockRaftActorContext.MockPayload("A"),
-                        new MockRaftActorContext.MockPayload("B"),
-                        new MockRaftActorContext.MockPayload("C"),
-                        new MockRaftActorContext.MockPayload("D")));
-
-                Snapshot snapshot = Snapshot.create(snapshotBytes.toByteArray(),
-                        Lists.<ReplicatedLogEntry>newArrayList(), 3, 1, 3, 1);
-
-                mockRaftActor.onReceiveRecover(new SnapshotOffer(new SnapshotMetadata(persistenceId, 100, 100), snapshot));
-
-                verify(mockRaftActor.delegate, times(0)).applyRecoverySnapshot(any(byte[].class));
-
-                mockRaftActor.onReceiveRecover(new ReplicatedLogImplEntry(0, 1, new MockRaftActorContext.MockPayload("A")));
-
-                ReplicatedLog replicatedLog = mockRaftActor.getReplicatedLog();
-
-                assertEquals("add replicated log entry", 0, replicatedLog.size());
-
-                mockRaftActor.onReceiveRecover(new ReplicatedLogImplEntry(1, 1, new MockRaftActorContext.MockPayload("A")));
-
-                assertEquals("add replicated log entry", 0, replicatedLog.size());
-
-                mockRaftActor.onReceiveRecover(new ApplyLogEntries(1));
-
-                assertEquals("commit index -1", -1, mockRaftActor.getRaftActorContext().getCommitIndex());
-
-                mockRaftActor.onReceiveRecover(new RaftActor.DeleteEntries(2));
-
-                assertEquals("remove log entries", 0, replicatedLog.size());
-
-                mockRaftActor.onReceiveRecover(new RaftActor.UpdateElectionTerm(10, "foobar"));
-
-                assertNotEquals("election term", 10, mockRaftActor.getRaftActorContext().getTermInformation().getCurrentTerm());
-                assertNotEquals("voted for", "foobar", mockRaftActor.getRaftActorContext().getTermInformation().getVotedFor());
-
-                mockRaftActor.onReceiveRecover(mock(RecoveryCompleted.class));
-            }};
-    }
-
-
-    @Test
-    public void testUpdatingElectionTermCallsDataPersistence() throws Exception {
-        new JavaTestKit(getSystem()) {
-            {
-                String persistenceId = factory.generateActorId("leader-");
-
-                DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
-
-                config.setHeartBeatInterval(new FiniteDuration(1, TimeUnit.DAYS));
-
-                CountDownLatch persistLatch = new CountDownLatch(1);
-                DataPersistenceProviderMonitor dataPersistenceProviderMonitor = new DataPersistenceProviderMonitor();
-                dataPersistenceProviderMonitor.setPersistLatch(persistLatch);
-
-                TestActorRef<MockRaftActor> mockActorRef = factory.createTestActor(MockRaftActor.props(persistenceId,
-                        Collections.<String, String>emptyMap(), Optional.<ConfigParams>of(config), dataPersistenceProviderMonitor), persistenceId);
+            assertEquals("Recovered state size", 6, mockRaftActor.getState().size());
 
-                MockRaftActor mockRaftActor = mockActorRef.underlyingActor();
-
-                mockRaftActor.waitForInitializeBehaviorComplete();
+            mockRaftActor.waitForInitializeBehaviorComplete();
 
-                mockRaftActor.getRaftActorContext().getTermInformation().updateAndPersist(10, "foobar");
+            assertEquals("getRaftState", RaftState.Follower, mockRaftActor.getRaftState());
+        }};
 
-                assertEquals("Persist called", true, persistLatch.await(5, TimeUnit.SECONDS));
-            }
-        };
+        TEST_LOG.info("testRaftActorRecoveryWithPersistenceEnabled ending");
     }
 
     @Test
-    public void testAddingReplicatedLogEntryCallsDataPersistence() throws Exception {
-        new JavaTestKit(getSystem()) {
-            {
-                String persistenceId = factory.generateActorId("leader-");
-
-                DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
-
-                config.setHeartBeatInterval(new FiniteDuration(1, TimeUnit.DAYS));
+    public void testRaftActorRecoveryWithPersistenceDisabled() throws Exception {
+        new JavaTestKit(getSystem()) {{
+            String persistenceId = factory.generateActorId("follower-");
 
-                DataPersistenceProvider dataPersistenceProvider = mock(DataPersistenceProvider.class);
+            DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
 
-                TestActorRef<MockRaftActor> mockActorRef = factory.createTestActor(MockRaftActor.props(persistenceId,
-                        Collections.<String, String>emptyMap(), Optional.<ConfigParams>of(config), dataPersistenceProvider), persistenceId);
+            config.setHeartBeatInterval(new FiniteDuration(1, TimeUnit.DAYS));
 
-                MockRaftActor mockRaftActor = mockActorRef.underlyingActor();
+            TestActorRef<MockRaftActor> ref = factory.createTestActor(MockRaftActor.props(persistenceId,
+                    ImmutableMap.<String, String>builder().put("member1", "address").build(),
+                    Optional.<ConfigParams>of(config), new NonPersistentDataProvider()), persistenceId);
 
-                mockRaftActor.waitForInitializeBehaviorComplete();
+            MockRaftActor mockRaftActor = ref.underlyingActor();
 
-                MockRaftActorContext.MockReplicatedLogEntry logEntry = new MockRaftActorContext.MockReplicatedLogEntry(10, 10, mock(Payload.class));
+            mockRaftActor.waitForRecoveryComplete();
 
-                mockRaftActor.getRaftActorContext().getReplicatedLog().appendAndPersist(logEntry);
+            mockRaftActor.waitForInitializeBehaviorComplete();
 
-                verify(dataPersistenceProvider).persist(eq(logEntry), any(Procedure.class));
-            }
-        };
+            assertEquals("getRaftState", RaftState.Follower, mockRaftActor.getRaftState());
+        }};
     }
 
     @Test
-    public void testRemovingReplicatedLogEntryCallsDataPersistence() throws Exception {
-        new JavaTestKit(getSystem()) {
-            {
-                String persistenceId = factory.generateActorId("leader-");
+    public void testRaftActorForwardsToRaftActorRecoverySupport() {
+        String persistenceId = factory.generateActorId("leader-");
 
-                DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
+        DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
 
-                config.setHeartBeatInterval(new FiniteDuration(1, TimeUnit.DAYS));
+        config.setHeartBeatInterval(new FiniteDuration(1, TimeUnit.DAYS));
 
-                DataPersistenceProvider dataPersistenceProvider = mock(DataPersistenceProvider.class);
+        TestActorRef<MockRaftActor> mockActorRef = factory.createTestActor(MockRaftActor.props(persistenceId,
+                Collections.<String, String>emptyMap(), Optional.<ConfigParams>of(config)), persistenceId);
 
-                TestActorRef<MockRaftActor> mockActorRef = factory.createTestActor(MockRaftActor.props(persistenceId,
-                        Collections.<String, String>emptyMap(), Optional.<ConfigParams>of(config), dataPersistenceProvider), persistenceId);
+        MockRaftActor mockRaftActor = mockActorRef.underlyingActor();
 
-                MockRaftActor mockRaftActor = mockActorRef.underlyingActor();
+        // Wait for akka's recovery to complete so it doesn't interfere.
+        mockRaftActor.waitForRecoveryComplete();
 
-                mockRaftActor.waitForInitializeBehaviorComplete();
+        RaftActorRecoverySupport mockSupport = mock(RaftActorRecoverySupport.class);
+        mockRaftActor.setRaftActorRecoverySupport(mockSupport );
 
-                mockRaftActor.getReplicatedLog().appendAndPersist(new MockRaftActorContext.MockReplicatedLogEntry(1, 0, mock(Payload.class)));
+        Snapshot snapshot = Snapshot.create(new byte[]{1}, Collections.<ReplicatedLogEntry>emptyList(), 3, 1, 3, 1);
+        SnapshotOffer snapshotOffer = new SnapshotOffer(new SnapshotMetadata("test", 6, 12345), snapshot);
+        mockRaftActor.handleRecover(snapshotOffer);
 
-                mockRaftActor.getRaftActorContext().getReplicatedLog().removeFromAndPersist(0);
+        MockRaftActorContext.MockReplicatedLogEntry logEntry = new MockRaftActorContext.MockReplicatedLogEntry(1,
+                1, new MockRaftActorContext.MockPayload("1", 5));
+        mockRaftActor.handleRecover(logEntry);
 
-                verify(dataPersistenceProvider, times(2)).persist(anyObject(), any(Procedure.class));
-            }
-        };
-    }
+        ApplyJournalEntries applyJournalEntries = new ApplyJournalEntries(2);
+        mockRaftActor.handleRecover(applyJournalEntries);
 
-    @Test
-    public void testApplyLogEntriesCallsDataPersistence() throws Exception {
-        new JavaTestKit(getSystem()) {
-            {
-                String persistenceId = factory.generateActorId("leader-");
+        ApplyLogEntries applyLogEntries = new ApplyLogEntries(0);
+        mockRaftActor.handleRecover(applyLogEntries);
 
-                DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
-
-                config.setHeartBeatInterval(new FiniteDuration(1, TimeUnit.DAYS));
+        DeleteEntries deleteEntries = new DeleteEntries(1);
+        mockRaftActor.handleRecover(deleteEntries);
 
-                DataPersistenceProvider dataPersistenceProvider = mock(DataPersistenceProvider.class);
-
-                TestActorRef<MockRaftActor> mockActorRef = factory.createTestActor(MockRaftActor.props(persistenceId,
-                        Collections.<String, String>emptyMap(), Optional.<ConfigParams>of(config), dataPersistenceProvider), persistenceId);
-
-                MockRaftActor mockRaftActor = mockActorRef.underlyingActor();
-
-                mockRaftActor.waitForInitializeBehaviorComplete();
+        org.opendaylight.controller.cluster.raft.RaftActor.DeleteEntries deprecatedDeleteEntries =
+                new org.opendaylight.controller.cluster.raft.RaftActor.DeleteEntries(1);
+        mockRaftActor.handleRecover(deprecatedDeleteEntries);
 
-                mockRaftActor.onReceiveCommand(new ApplyLogEntries(10));
+        UpdateElectionTerm updateElectionTerm = new UpdateElectionTerm(5, "member2");
+        mockRaftActor.handleRecover(updateElectionTerm);
 
-                verify(dataPersistenceProvider, times(1)).persist(anyObject(), any(Procedure.class));
+        org.opendaylight.controller.cluster.raft.RaftActor.UpdateElectionTerm deprecatedUpdateElectionTerm =
+                new org.opendaylight.controller.cluster.raft.RaftActor.UpdateElectionTerm(6, "member3");
+        mockRaftActor.handleRecover(deprecatedUpdateElectionTerm);
 
-            }
-
-        };
+        verify(mockSupport).handleRecoveryMessage(same(snapshotOffer));
+        verify(mockSupport).handleRecoveryMessage(same(logEntry));
+        verify(mockSupport).handleRecoveryMessage(same(applyJournalEntries));
+        verify(mockSupport).handleRecoveryMessage(same(applyLogEntries));
+        verify(mockSupport).handleRecoveryMessage(same(deleteEntries));
+        verify(mockSupport).handleRecoveryMessage(same(deprecatedDeleteEntries));
+        verify(mockSupport).handleRecoveryMessage(same(updateElectionTerm));
+        verify(mockSupport).handleRecoveryMessage(same(deprecatedUpdateElectionTerm));
     }
 
     @Test
-    public void testCaptureSnapshotReplyCallsDataPersistence() throws Exception {
-        new JavaTestKit(getSystem()) {
-            {
-                String persistenceId = factory.generateActorId("leader-");
+    public void testRaftActorForwardsToRaftActorSnapshotMessageSupport() {
+        String persistenceId = factory.generateActorId("leader-");
 
-                DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
+        DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
 
-                config.setHeartBeatInterval(new FiniteDuration(1, TimeUnit.DAYS));
+        config.setHeartBeatInterval(new FiniteDuration(1, TimeUnit.DAYS));
 
-                DataPersistenceProvider dataPersistenceProvider = mock(DataPersistenceProvider.class);
+        RaftActorSnapshotMessageSupport mockSupport = mock(RaftActorSnapshotMessageSupport.class);
 
-                TestActorRef<MockRaftActor> mockActorRef = factory.createTestActor(
-                        MockRaftActor.props(persistenceId, Collections.<String, String>emptyMap(),
-                                Optional.<ConfigParams>of(config), dataPersistenceProvider), persistenceId);
+        TestActorRef<MockRaftActor> mockActorRef = factory.createTestActor(MockRaftActor.props(persistenceId,
+                Collections.<String, String>emptyMap(), Optional.<ConfigParams>of(config), mockSupport), persistenceId);
 
-                MockRaftActor mockRaftActor = mockActorRef.underlyingActor();
+        MockRaftActor mockRaftActor = mockActorRef.underlyingActor();
 
-                mockRaftActor.waitForInitializeBehaviorComplete();
+        // Wait for akka's recovery to complete so it doesn't interfere.
+        mockRaftActor.waitForRecoveryComplete();
 
-                ByteString snapshotBytes = fromObject(Arrays.asList(
-                        new MockRaftActorContext.MockPayload("A"),
-                        new MockRaftActorContext.MockPayload("B"),
-                        new MockRaftActorContext.MockPayload("C"),
-                        new MockRaftActorContext.MockPayload("D")));
+        ApplySnapshot applySnapshot = new ApplySnapshot(mock(Snapshot.class));
+        doReturn(true).when(mockSupport).handleSnapshotMessage(same(applySnapshot));
+        mockRaftActor.handleCommand(applySnapshot);
 
-                mockRaftActor.onReceiveCommand(new CaptureSnapshot(-1, 1,-1, 1, -1, 1));
+        CaptureSnapshot captureSnapshot = new CaptureSnapshot(1, 1, 1, 1, 0, 1, null);
+        doReturn(true).when(mockSupport).handleSnapshotMessage(same(captureSnapshot));
+        mockRaftActor.handleCommand(captureSnapshot);
 
-                RaftActorContext raftActorContext = mockRaftActor.getRaftActorContext();
+        CaptureSnapshotReply captureSnapshotReply = new CaptureSnapshotReply(new byte[0]);
+        doReturn(true).when(mockSupport).handleSnapshotMessage(same(captureSnapshotReply));
+        mockRaftActor.handleCommand(captureSnapshotReply);
 
-                mockRaftActor.setCurrentBehavior(new Leader(raftActorContext));
+        SaveSnapshotSuccess saveSnapshotSuccess = new SaveSnapshotSuccess(mock(SnapshotMetadata.class));
+        doReturn(true).when(mockSupport).handleSnapshotMessage(same(saveSnapshotSuccess));
+        mockRaftActor.handleCommand(saveSnapshotSuccess);
 
-                mockRaftActor.onReceiveCommand(new CaptureSnapshotReply(snapshotBytes.toByteArray()));
+        SaveSnapshotFailure saveSnapshotFailure = new SaveSnapshotFailure(mock(SnapshotMetadata.class), new Throwable());
+        doReturn(true).when(mockSupport).handleSnapshotMessage(same(saveSnapshotFailure));
+        mockRaftActor.handleCommand(saveSnapshotFailure);
 
-                verify(dataPersistenceProvider).saveSnapshot(anyObject());
+        doReturn(true).when(mockSupport).handleSnapshotMessage(same(RaftActorSnapshotMessageSupport.COMMIT_SNAPSHOT));
+        mockRaftActor.handleCommand(RaftActorSnapshotMessageSupport.COMMIT_SNAPSHOT);
 
-            }
-        };
+        verify(mockSupport).handleSnapshotMessage(same(applySnapshot));
+        verify(mockSupport).handleSnapshotMessage(same(captureSnapshot));
+        verify(mockSupport).handleSnapshotMessage(same(captureSnapshotReply));
+        verify(mockSupport).handleSnapshotMessage(same(saveSnapshotSuccess));
+        verify(mockSupport).handleSnapshotMessage(same(saveSnapshotFailure));
+        verify(mockSupport).handleSnapshotMessage(same(RaftActorSnapshotMessageSupport.COMMIT_SNAPSHOT));
     }
 
     @Test
-    public void testSaveSnapshotSuccessCallsDataPersistence() throws Exception {
+    public void testApplyJournalEntriesCallsDataPersistence() throws Exception {
         new JavaTestKit(getSystem()) {
             {
                 String persistenceId = factory.generateActorId("leader-");
@@ -727,46 +341,14 @@ public class RaftActorTest extends AbstractActorTest {
 
                 mockRaftActor.waitForInitializeBehaviorComplete();
 
-                mockRaftActor.getReplicatedLog().append(new MockRaftActorContext.MockReplicatedLogEntry(1, 0, mock(Payload.class)));
-                mockRaftActor.getReplicatedLog().append(new MockRaftActorContext.MockReplicatedLogEntry(1, 1, mock(Payload.class)));
-                mockRaftActor.getReplicatedLog().append(new MockRaftActorContext.MockReplicatedLogEntry(1, 2, mock(Payload.class)));
-                mockRaftActor.getReplicatedLog().append(new MockRaftActorContext.MockReplicatedLogEntry(1, 3, mock(Payload.class)));
-                mockRaftActor.getReplicatedLog().append(new MockRaftActorContext.MockReplicatedLogEntry(1, 4, mock(Payload.class)));
-
-                ByteString snapshotBytes = fromObject(Arrays.asList(
-                        new MockRaftActorContext.MockPayload("A"),
-                        new MockRaftActorContext.MockPayload("B"),
-                        new MockRaftActorContext.MockPayload("C"),
-                        new MockRaftActorContext.MockPayload("D")));
-
-                RaftActorContext raftActorContext = mockRaftActor.getRaftActorContext();
-                mockRaftActor.setCurrentBehavior(new Follower(raftActorContext));
-
-                long replicatedToAllIndex = 1;
-                mockRaftActor.onReceiveCommand(new CaptureSnapshot(-1, 1, 2, 1, replicatedToAllIndex, 1));
-
-                verify(mockRaftActor.delegate).createSnapshot();
+                mockRaftActor.waitUntilLeader();
 
-                mockRaftActor.onReceiveCommand(new CaptureSnapshotReply(snapshotBytes.toByteArray()));
+                mockRaftActor.onReceiveCommand(new ApplyJournalEntries(10));
 
-                mockRaftActor.onReceiveCommand(new SaveSnapshotSuccess(new SnapshotMetadata("foo", 100, 100)));
-
-                verify(dataPersistenceProvider).deleteSnapshots(any(SnapshotSelectionCriteria.class));
-
-                verify(dataPersistenceProvider).deleteMessages(100);
-
-                assertEquals(3, mockRaftActor.getReplicatedLog().size());
-                assertEquals(1, mockRaftActor.getCurrentBehavior().getReplicatedToAllIndex());
-
-                assertNotNull(mockRaftActor.getReplicatedLog().get(2));
-                assertNotNull(mockRaftActor.getReplicatedLog().get(3));
-                assertNotNull(mockRaftActor.getReplicatedLog().get(4));
-
-                // Index 2 will not be in the log because it was removed due to snapshotting
-                assertNull(mockRaftActor.getReplicatedLog().get(1));
-                assertNull(mockRaftActor.getReplicatedLog().get(0));
+                verify(dataPersistenceProvider, times(2)).persist(anyObject(), any(Procedure.class));
 
             }
+
         };
     }
 
@@ -795,112 +377,102 @@ public class RaftActorTest extends AbstractActorTest {
 
                 mockRaftActor.onReceiveCommand(new ApplyState(mockActorRef, "apply-state", entry));
 
-                verify(mockRaftActor.delegate).applyState(eq(mockActorRef), eq("apply-state"), anyObject());
+                verify(mockRaftActor.actorDelegate).applyState(eq(mockActorRef), eq("apply-state"), anyObject());
 
             }
         };
     }
 
     @Test
-    public void testApplySnapshot() throws Exception {
-        new JavaTestKit(getSystem()) {
-            {
-                String persistenceId = factory.generateActorId("leader-");
-
-                DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
-
-                config.setHeartBeatInterval(new FiniteDuration(1, TimeUnit.DAYS));
-
-                DataPersistenceProviderMonitor dataPersistenceProviderMonitor = new DataPersistenceProviderMonitor();
-
-                TestActorRef<MockRaftActor> mockActorRef = factory.createTestActor(MockRaftActor.props(persistenceId,
-                        Collections.<String, String>emptyMap(), Optional.<ConfigParams>of(config), dataPersistenceProviderMonitor), persistenceId);
-
-                MockRaftActor mockRaftActor = mockActorRef.underlyingActor();
-
-                mockRaftActor.waitForInitializeBehaviorComplete();
-
-                ReplicatedLog oldReplicatedLog = mockRaftActor.getReplicatedLog();
-
-                oldReplicatedLog.append(new MockRaftActorContext.MockReplicatedLogEntry(1, 0, mock(Payload.class)));
-                oldReplicatedLog.append(new MockRaftActorContext.MockReplicatedLogEntry(1, 1, mock(Payload.class)));
-                oldReplicatedLog.append(
-                        new MockRaftActorContext.MockReplicatedLogEntry(1, 2,
-                                mock(Payload.class)));
-
-                ByteString snapshotBytes = fromObject(Arrays.asList(
-                        new MockRaftActorContext.MockPayload("A"),
-                        new MockRaftActorContext.MockPayload("B"),
-                        new MockRaftActorContext.MockPayload("C"),
-                        new MockRaftActorContext.MockPayload("D")));
-
-                Snapshot snapshot = mock(Snapshot.class);
-
-                doReturn(snapshotBytes.toByteArray()).when(snapshot).getState();
-
-                doReturn(3L).when(snapshot).getLastAppliedIndex();
+    public void testRaftRoleChangeNotifierWhenRaftActorHasNoPeers() throws Exception {
+        new JavaTestKit(getSystem()) {{
+            TestActorRef<MessageCollectorActor> notifierActor = factory.createTestActor(
+                    Props.create(MessageCollectorActor.class));
+            MessageCollectorActor.waitUntilReady(notifierActor);
 
-                mockRaftActor.onReceiveCommand(new ApplySnapshot(snapshot));
+            DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
+            long heartBeatInterval = 100;
+            config.setHeartBeatInterval(FiniteDuration.create(heartBeatInterval, TimeUnit.MILLISECONDS));
+            config.setElectionTimeoutFactor(20);
 
-                verify(mockRaftActor.delegate).applySnapshot(eq(snapshot.getState()));
+            String persistenceId = factory.generateActorId("notifier-");
 
-                assertTrue("The replicatedLog should have changed",
-                        oldReplicatedLog != mockRaftActor.getReplicatedLog());
+            TestActorRef<MockRaftActor> raftActorRef = factory.createTestActor(MockRaftActor.props(persistenceId,
+                    Collections.<String, String>emptyMap(), Optional.<ConfigParams>of(config), notifierActor,
+                    new NonPersistentDataProvider()), persistenceId);
 
-                assertEquals("lastApplied should be same as in the snapshot",
-                        (Long) 3L, mockRaftActor.getLastApplied());
+            List<RoleChanged> matches =  MessageCollectorActor.expectMatching(notifierActor, RoleChanged.class, 3);
 
-                assertEquals(0, mockRaftActor.getReplicatedLog().size());
 
-            }
-        };
-    }
+            // check if the notifier got a role change from null to Follower
+            RoleChanged raftRoleChanged = matches.get(0);
+            assertEquals(persistenceId, raftRoleChanged.getMemberId());
+            assertNull(raftRoleChanged.getOldRole());
+            assertEquals(RaftState.Follower.name(), raftRoleChanged.getNewRole());
 
-    @Test
-    public void testSaveSnapshotFailure() throws Exception {
-        new JavaTestKit(getSystem()) {
-            {
-                String persistenceId = factory.generateActorId("leader-");
+            // check if the notifier got a role change from Follower to Candidate
+            raftRoleChanged = matches.get(1);
+            assertEquals(persistenceId, raftRoleChanged.getMemberId());
+            assertEquals(RaftState.Follower.name(), raftRoleChanged.getOldRole());
+            assertEquals(RaftState.Candidate.name(), raftRoleChanged.getNewRole());
 
-                DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
+            // check if the notifier got a role change from Candidate to Leader
+            raftRoleChanged = matches.get(2);
+            assertEquals(persistenceId, raftRoleChanged.getMemberId());
+            assertEquals(RaftState.Candidate.name(), raftRoleChanged.getOldRole());
+            assertEquals(RaftState.Leader.name(), raftRoleChanged.getNewRole());
 
-                config.setHeartBeatInterval(new FiniteDuration(1, TimeUnit.DAYS));
+            LeaderStateChanged leaderStateChange = MessageCollectorActor.expectFirstMatching(
+                    notifierActor, LeaderStateChanged.class);
 
-                DataPersistenceProviderMonitor dataPersistenceProviderMonitor = new DataPersistenceProviderMonitor();
+            assertEquals(raftRoleChanged.getMemberId(), leaderStateChange.getLeaderId());
+            assertEquals(MockRaftActor.PAYLOAD_VERSION, leaderStateChange.getLeaderPayloadVersion());
 
-                TestActorRef<MockRaftActor> mockActorRef = factory.createTestActor(MockRaftActor.props(persistenceId,
-                        Collections.<String, String>emptyMap(), Optional.<ConfigParams>of(config), dataPersistenceProviderMonitor), persistenceId);
+            notifierActor.underlyingActor().clear();
 
-                MockRaftActor mockRaftActor = mockActorRef.underlyingActor();
+            MockRaftActor raftActor = raftActorRef.underlyingActor();
+            final String newLeaderId = "new-leader";
+            final short newLeaderVersion = 6;
+            Follower follower = new Follower(raftActor.getRaftActorContext()) {
+                @Override
+                public RaftActorBehavior handleMessage(ActorRef sender, Object message) {
+                    leaderId = newLeaderId;
+                    setLeaderPayloadVersion(newLeaderVersion);
+                    return this;
+                }
+            };
 
-                mockRaftActor.waitForInitializeBehaviorComplete();
+            raftActor.changeCurrentBehavior(follower);
 
-                ByteString snapshotBytes = fromObject(Arrays.asList(
-                        new MockRaftActorContext.MockPayload("A"),
-                        new MockRaftActorContext.MockPayload("B"),
-                        new MockRaftActorContext.MockPayload("C"),
-                        new MockRaftActorContext.MockPayload("D")));
+            leaderStateChange = MessageCollectorActor.expectFirstMatching(notifierActor, LeaderStateChanged.class);
+            assertEquals(persistenceId, leaderStateChange.getMemberId());
+            assertEquals(null, leaderStateChange.getLeaderId());
 
-                RaftActorContext raftActorContext = mockRaftActor.getRaftActorContext();
+            raftRoleChanged = MessageCollectorActor.expectFirstMatching(notifierActor, RoleChanged.class);
+            assertEquals(RaftState.Leader.name(), raftRoleChanged.getOldRole());
+            assertEquals(RaftState.Follower.name(), raftRoleChanged.getNewRole());
 
-                mockRaftActor.setCurrentBehavior(new Leader(raftActorContext));
+            notifierActor.underlyingActor().clear();
 
-                mockRaftActor.onReceiveCommand(new CaptureSnapshot(-1, 1, -1, 1, -1, 1));
+            raftActor.handleCommand("any");
 
-                mockRaftActor.onReceiveCommand(new CaptureSnapshotReply(snapshotBytes.toByteArray()));
+            leaderStateChange = MessageCollectorActor.expectFirstMatching(notifierActor, LeaderStateChanged.class);
+            assertEquals(persistenceId, leaderStateChange.getMemberId());
+            assertEquals(newLeaderId, leaderStateChange.getLeaderId());
+            assertEquals(newLeaderVersion, leaderStateChange.getLeaderPayloadVersion());
 
-                mockRaftActor.onReceiveCommand(new SaveSnapshotFailure(new SnapshotMetadata("foobar", 10L, 1234L),
-                        new Exception()));
+            notifierActor.underlyingActor().clear();
 
-                assertEquals("Snapshot index should not have advanced because save snapshot failed", -1,
-                        mockRaftActor.getReplicatedLog().getSnapshotIndex());
+            raftActor.handleCommand("any");
 
-            }
-        };
+            Uninterruptibles.sleepUninterruptibly(505, TimeUnit.MILLISECONDS);
+            leaderStateChange = MessageCollectorActor.getFirstMatching(notifierActor, LeaderStateChanged.class);
+            assertNull(leaderStateChange);
+        }};
     }
 
     @Test
-    public void testRaftRoleChangeNotifier() throws Exception {
+    public void testRaftRoleChangeNotifierWhenRaftActorHasPeers() throws Exception {
         new JavaTestKit(getSystem()) {{
             ActorRef notifierActor = factory.createActor(Props.create(MessageCollectorActor.class));
             MessageCollectorActor.waitUntilReady(notifierActor);
@@ -912,8 +484,8 @@ public class RaftActorTest extends AbstractActorTest {
 
             String persistenceId = factory.generateActorId("notifier-");
 
-            factory.createTestActor(MockRaftActor.props(persistenceId,
-                    Collections.<String, String>emptyMap(), Optional.<ConfigParams>of(config), notifierActor), persistenceId);
+            factory.createActor(MockRaftActor.props(persistenceId,
+                    ImmutableMap.of("leader", "fake/path"), Optional.<ConfigParams>of(config), notifierActor), persistenceId);
 
             List<RoleChanged> matches =  null;
             for(int i = 0; i < 5000 / heartBeatInterval; i++) {
@@ -925,7 +497,8 @@ public class RaftActorTest extends AbstractActorTest {
                 Uninterruptibles.sleepUninterruptibly(heartBeatInterval, TimeUnit.MILLISECONDS);
             }
 
-            assertEquals(3, matches.size());
+            assertNotNull(matches);
+            assertEquals(2, matches.size());
 
             // check if the notifier got a role change from null to Follower
             RoleChanged raftRoleChanged = matches.get(0);
@@ -939,11 +512,6 @@ public class RaftActorTest extends AbstractActorTest {
             assertEquals(RaftState.Follower.name(), raftRoleChanged.getOldRole());
             assertEquals(RaftState.Candidate.name(), raftRoleChanged.getNewRole());
 
-            // check if the notifier got a role change from Candidate to Leader
-            raftRoleChanged = matches.get(2);
-            assertEquals(persistenceId, raftRoleChanged.getMemberId());
-            assertEquals(RaftState.Candidate.name(), raftRoleChanged.getOldRole());
-            assertEquals(RaftState.Leader.name(), raftRoleChanged.getNewRole());
         }};
     }
 
@@ -989,22 +557,23 @@ public class RaftActorTest extends AbstractActorTest {
 
                 assertEquals(8, leaderActor.getReplicatedLog().size());
 
-                leaderActor.onReceiveCommand(new CaptureSnapshot(6, 1, 4, 1, 4, 1));
+                leaderActor.getRaftActorContext().getSnapshotManager()
+                        .capture(new MockRaftActorContext.MockReplicatedLogEntry(1, 6,
+                                new MockRaftActorContext.MockPayload("x")), 4);
 
-                leaderActor.getRaftActorContext().setSnapshotCaptureInitiated(true);
-                verify(leaderActor.delegate).createSnapshot();
+                verify(leaderActor.snapshotCohortDelegate).createSnapshot(any(ActorRef.class));
 
                 assertEquals(8, leaderActor.getReplicatedLog().size());
 
                 assertEquals(RaftState.Leader, leaderActor.getCurrentBehavior().state());
                 //fake snapshot on index 5
-                leaderActor.onReceiveCommand(new AppendEntriesReply(follower1Id, 1, true, 5, 1));
+                leaderActor.onReceiveCommand(new AppendEntriesReply(follower1Id, 1, true, 5, 1, (short)0));
 
                 assertEquals(8, leaderActor.getReplicatedLog().size());
 
                 //fake snapshot on index 6
                 assertEquals(RaftState.Leader, leaderActor.getCurrentBehavior().state());
-                leaderActor.onReceiveCommand(new AppendEntriesReply(follower1Id, 1, true, 6, 1));
+                leaderActor.onReceiveCommand(new AppendEntriesReply(follower1Id, 1, true, 6, 1, (short)0));
                 assertEquals(8, leaderActor.getReplicatedLog().size());
 
                 assertEquals(RaftState.Leader, leaderActor.getCurrentBehavior().state());
@@ -1017,8 +586,14 @@ public class RaftActorTest extends AbstractActorTest {
                         new MockRaftActorContext.MockPayload("foo-2"),
                         new MockRaftActorContext.MockPayload("foo-3"),
                         new MockRaftActorContext.MockPayload("foo-4")));
-                leaderActor.onReceiveCommand(new CaptureSnapshotReply(snapshotBytes.toByteArray()));
-                assertFalse(leaderActor.getRaftActorContext().isSnapshotCaptureInitiated());
+
+                leaderActor.getRaftActorContext().getSnapshotManager().persist(snapshotBytes.toByteArray(),
+                        leader, Runtime.getRuntime().totalMemory());
+
+                assertTrue(leaderActor.getRaftActorContext().getSnapshotManager().isCapturing());
+
+                // The commit is needed to complete the snapshot creation process
+                leaderActor.getRaftActorContext().getSnapshotManager().commit(-1, leader);
 
                 // capture snapshot reply should remove the snapshotted entries only
                 assertEquals(3, leaderActor.getReplicatedLog().size());
@@ -1029,7 +604,7 @@ public class RaftActorTest extends AbstractActorTest {
                         new ReplicatedLogImplEntry(8, 1, new MockRaftActorContext.MockPayload("foo-8")));
 
                 //fake snapshot on index 7, since lastApplied = 7 , we would keep the last applied
-                leaderActor.onReceiveCommand(new AppendEntriesReply(follower1Id, 1, true, 7, 1));
+                leaderActor.onReceiveCommand(new AppendEntriesReply(follower1Id, 1, true, 7, 1, (short)0));
                 assertEquals(2, leaderActor.getReplicatedLog().size());
                 assertEquals(8, leaderActor.getReplicatedLog().lastIndex());
 
@@ -1081,10 +656,11 @@ public class RaftActorTest extends AbstractActorTest {
                 assertEquals(6, followerActor.getReplicatedLog().size());
 
                 //snapshot on 4
-                followerActor.onReceiveCommand(new CaptureSnapshot(5, 1, 4, 1, 4, 1));
+                followerActor.getRaftActorContext().getSnapshotManager().capture(
+                        new MockRaftActorContext.MockReplicatedLogEntry(1, 5,
+                                new MockRaftActorContext.MockPayload("D")), 4);
 
-                followerActor.getRaftActorContext().setSnapshotCaptureInitiated(true);
-                verify(followerActor.delegate).createSnapshot();
+                verify(followerActor.snapshotCohortDelegate).createSnapshot(any(ActorRef.class));
 
                 assertEquals(6, followerActor.getReplicatedLog().size());
 
@@ -1094,7 +670,7 @@ public class RaftActorTest extends AbstractActorTest {
                                 (ReplicatedLogEntry) new MockRaftActorContext.MockReplicatedLogEntry(1, 6,
                                         new MockRaftActorContext.MockPayload("foo-6"))
                         );
-                followerActor.onReceiveCommand(new AppendEntries(1, leaderId, 5, 1, entries, 5, 5));
+                followerActor.onReceiveCommand(new AppendEntries(1, leaderId, 5, 1, entries, 5, 5, (short)0));
                 assertEquals(7, followerActor.getReplicatedLog().size());
 
                 //fake snapshot on index 7
@@ -1105,7 +681,7 @@ public class RaftActorTest extends AbstractActorTest {
                                 (ReplicatedLogEntry) new MockRaftActorContext.MockReplicatedLogEntry(1, 7,
                                         new MockRaftActorContext.MockPayload("foo-7"))
                         );
-                followerActor.onReceiveCommand(new AppendEntries(1, leaderId, 6, 1, entries, 6, 6));
+                followerActor.onReceiveCommand(new AppendEntries(1, leaderId, 6, 1, entries, 6, 6, (short)0));
                 assertEquals(8, followerActor.getReplicatedLog().size());
 
                 assertEquals(RaftState.Follower, followerActor.getCurrentBehavior().state());
@@ -1118,7 +694,10 @@ public class RaftActorTest extends AbstractActorTest {
                         new MockRaftActorContext.MockPayload("foo-3"),
                         new MockRaftActorContext.MockPayload("foo-4")));
                 followerActor.onReceiveCommand(new CaptureSnapshotReply(snapshotBytes.toByteArray()));
-                assertFalse(followerActor.getRaftActorContext().isSnapshotCaptureInitiated());
+                assertTrue(followerActor.getRaftActorContext().getSnapshotManager().isCapturing());
+
+                // The commit is needed to complete the snapshot creation process
+                followerActor.getRaftActorContext().getSnapshotManager().commit(-1, follower);
 
                 // capture snapshot reply should remove the snapshotted entries only till replicatedToAllIndex
                 assertEquals(3, followerActor.getReplicatedLog().size()); //indexes 5,6,7 left in the log
@@ -1130,7 +709,7 @@ public class RaftActorTest extends AbstractActorTest {
                                         new MockRaftActorContext.MockPayload("foo-7"))
                         );
                 // send an additional entry 8 with leaderCommit = 7
-                followerActor.onReceiveCommand(new AppendEntries(1, leaderId, 7, 1, entries, 7, 7));
+                followerActor.onReceiveCommand(new AppendEntries(1, leaderId, 7, 1, entries, 7, 7, (short)0));
 
                 // 7 and 8, as lastapplied is 7
                 assertEquals(2, followerActor.getReplicatedLog().size());
@@ -1188,12 +767,12 @@ public class RaftActorTest extends AbstractActorTest {
                 assertEquals(5, leaderActor.getReplicatedLog().size());
                 assertEquals(RaftState.Leader, leaderActor.getCurrentBehavior().state());
 
-                leaderActor.onReceiveCommand(new AppendEntriesReply(follower1Id, 1, true, 9, 1));
+                leaderActor.onReceiveCommand(new AppendEntriesReply(follower1Id, 1, true, 9, 1, (short)0));
                 assertEquals(5, leaderActor.getReplicatedLog().size());
                 assertEquals(RaftState.Leader, leaderActor.getCurrentBehavior().state());
 
                 // set the 2nd follower nextIndex to 1 which has been snapshotted
-                leaderActor.onReceiveCommand(new AppendEntriesReply(follower2Id, 1, true, 0, 1));
+                leaderActor.onReceiveCommand(new AppendEntriesReply(follower2Id, 1, true, 0, 1, (short)0));
                 assertEquals(5, leaderActor.getReplicatedLog().size());
                 assertEquals(RaftState.Leader, leaderActor.getCurrentBehavior().state());
 
@@ -1206,7 +785,7 @@ public class RaftActorTest extends AbstractActorTest {
 
 
                 //reply from a slow follower does not initiate a fake snapshot
-                leaderActor.onReceiveCommand(new AppendEntriesReply(follower2Id, 1, true, 9, 1));
+                leaderActor.onReceiveCommand(new AppendEntriesReply(follower2Id, 1, true, 9, 1, (short)0));
                 assertEquals("Fake snapshot should not happen when Initiate is in progress", 5, leaderActor.getReplicatedLog().size());
 
                 ByteString snapshotBytes = fromObject(Arrays.asList(
@@ -1216,49 +795,17 @@ public class RaftActorTest extends AbstractActorTest {
                         new MockRaftActorContext.MockPayload("foo-3"),
                         new MockRaftActorContext.MockPayload("foo-4")));
                 leaderActor.onReceiveCommand(new CaptureSnapshotReply(snapshotBytes.toByteArray()));
-                assertFalse(leaderActor.getRaftActorContext().isSnapshotCaptureInitiated());
+                assertTrue(leaderActor.getRaftActorContext().getSnapshotManager().isCapturing());
 
                 assertEquals("Real snapshot didn't clear the log till replicatedToAllIndex", 0, leaderActor.getReplicatedLog().size());
 
                 //reply from a slow follower after should not raise errors
-                leaderActor.onReceiveCommand(new AppendEntriesReply(follower2Id, 1, true, 5, 1));
+                leaderActor.onReceiveCommand(new AppendEntriesReply(follower2Id, 1, true, 5, 1, (short)0));
                 assertEquals(0, leaderActor.getReplicatedLog().size());
             }
         };
     }
 
-
-    private static class NonPersistentProvider implements DataPersistenceProvider {
-        @Override
-        public boolean isRecoveryApplicable() {
-            return false;
-        }
-
-        @Override
-        public <T> void persist(T o, Procedure<T> procedure) {
-            try {
-                procedure.apply(o);
-            } catch (Exception e) {
-                e.printStackTrace();
-            }
-        }
-
-        @Override
-        public void saveSnapshot(Object o) {
-
-        }
-
-        @Override
-        public void deleteSnapshots(SnapshotSelectionCriteria criteria) {
-
-        }
-
-        @Override
-        public void deleteMessages(long sequenceNumber) {
-
-        }
-    }
-
     @Test
     public void testRealSnapshotWhenReplicatedToAllIndexMinusOne() throws Exception {
         new JavaTestKit(getSystem()) {{
@@ -1268,9 +815,9 @@ public class RaftActorTest extends AbstractActorTest {
             config.setIsolatedLeaderCheckInterval(new FiniteDuration(1, TimeUnit.DAYS));
             config.setSnapshotBatchCount(5);
 
-            DataPersistenceProvider dataPersistenceProvider = new NonPersistentProvider();
+            DataPersistenceProvider dataPersistenceProvider = new NonPersistentDataProvider();
 
-            Map<String, String> peerAddresses = new HashMap<>();
+            Map<String, String> peerAddresses = ImmutableMap.<String, String>builder().put("member1", "address").build();
 
             TestActorRef<MockRaftActor> mockActorRef = factory.createTestActor(
                     MockRaftActor.props(persistenceId, peerAddresses,
@@ -1292,15 +839,16 @@ public class RaftActorTest extends AbstractActorTest {
             leaderActor.setCurrentBehavior(leader);
             assertEquals(RaftState.Leader, leaderActor.getCurrentBehavior().state());
 
-            // Persist another entry (this will cause a CaptureSnapshot to be triggered
-            leaderActor.persistData(mockActorRef, "x", new MockRaftActorContext.MockPayload("duh"));
+            // Simulate an install snaphost to a follower.
+            leaderActor.getRaftActorContext().getSnapshotManager().captureToInstall(
+                    leaderActor.getReplicatedLog().last(), -1, "member1");
 
             // Now send a CaptureSnapshotReply
             mockActorRef.tell(new CaptureSnapshotReply(fromObject("foo").toByteArray()), mockActorRef);
 
             // Trimming log in this scenario is a no-op
             assertEquals(-1, leaderActor.getReplicatedLog().getSnapshotIndex());
-            assertFalse(leaderActor.getRaftActorContext().isSnapshotCaptureInitiated());
+            assertTrue(leaderActor.getRaftActorContext().getSnapshotManager().isCapturing());
             assertEquals(-1, leader.getReplicatedToAllIndex());
 
         }};
@@ -1315,9 +863,9 @@ public class RaftActorTest extends AbstractActorTest {
             config.setIsolatedLeaderCheckInterval(new FiniteDuration(1, TimeUnit.DAYS));
             config.setSnapshotBatchCount(5);
 
-            DataPersistenceProvider dataPersistenceProvider = new NonPersistentProvider();
+            DataPersistenceProvider dataPersistenceProvider = new NonPersistentDataProvider();
 
-            Map<String, String> peerAddresses = new HashMap<>();
+            Map<String, String> peerAddresses = ImmutableMap.<String, String>builder().put("member1", "address").build();
 
             TestActorRef<MockRaftActor> mockActorRef = factory.createTestActor(
                     MockRaftActor.props(persistenceId, peerAddresses,
@@ -1343,13 +891,13 @@ public class RaftActorTest extends AbstractActorTest {
 
             // Trimming log in this scenario is a no-op
             assertEquals(3, leaderActor.getReplicatedLog().getSnapshotIndex());
-            assertFalse(leaderActor.getRaftActorContext().isSnapshotCaptureInitiated());
+            assertTrue(leaderActor.getRaftActorContext().getSnapshotManager().isCapturing());
             assertEquals(3, leader.getReplicatedToAllIndex());
 
         }};
     }
 
-    private ByteString fromObject(Object snapshot) throws Exception {
+    public static ByteString fromObject(Object snapshot) throws Exception {
         ByteArrayOutputStream b = null;
         ObjectOutputStream o = null;
         try {