Merge branch 'stable-3.4'

* stable-3.4:
  Fix the default logic in managing refs-filter
  Reuse Gerrit code for head update
  Add HEAD update REST API endpoint
  Add project initialisation during fetch REST Api call
  Add project delete REST API endpoint

Change-Id: I006a7b86b05ac14b87efa6c38c3c4d2fe7e25b12
diff --git a/src/main/java/com/googlesource/gerrit/plugins/replication/pull/FetchOne.java b/src/main/java/com/googlesource/gerrit/plugins/replication/pull/FetchOne.java
index d4e22d9..a10a658 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/replication/pull/FetchOne.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/replication/pull/FetchOne.java
@@ -34,7 +34,6 @@
 import com.googlesource.gerrit.plugins.replication.pull.fetch.Fetch;
 import com.googlesource.gerrit.plugins.replication.pull.fetch.FetchFactory;
 import com.googlesource.gerrit.plugins.replication.pull.fetch.RefUpdateState;
-import com.jcraft.jsch.JSchException;
 import java.io.IOException;
 import java.util.Collection;
 import java.util.HashSet;
@@ -314,9 +313,7 @@
       stateLog.error("Cannot replicate from " + uri, e, getStatesAsArray());
     } catch (TransportException e) {
       Throwable cause = e.getCause();
-      if (cause instanceof JSchException && cause.getMessage().startsWith("UnknownHostKey:")) {
-        repLog.error("Cannot replicate from {}: {}", uri, cause.getMessage());
-      } else if (e instanceof LockFailureException) {
+      if (e instanceof LockFailureException) {
         lockRetryCount++;
         // The LockFailureException message contains both URI and reason
         // for this failure.
diff --git a/src/main/java/com/googlesource/gerrit/plugins/replication/pull/FetchRefReplicatedEvent.java b/src/main/java/com/googlesource/gerrit/plugins/replication/pull/FetchRefReplicatedEvent.java
index 8bf257e..0eabf42 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/replication/pull/FetchRefReplicatedEvent.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/replication/pull/FetchRefReplicatedEvent.java
@@ -15,30 +15,23 @@
 package com.googlesource.gerrit.plugins.replication.pull;
 
 import com.google.gerrit.entities.Project;
-import com.google.gerrit.server.events.RefEvent;
+import com.googlesource.gerrit.plugins.replication.events.RemoteRefReplicationEvent;
 import java.util.Objects;
 import org.eclipse.jgit.lib.RefUpdate;
+import org.eclipse.jgit.transport.URIish;
 
-public class FetchRefReplicatedEvent extends RefEvent {
+public class FetchRefReplicatedEvent extends RemoteRefReplicationEvent {
   static final String TYPE = "fetch-ref-replicated";
 
-  final String project;
-  final String ref;
-  final String sourceNode;
-  final String status;
   final RefUpdate.Result refUpdateResult;
 
   public FetchRefReplicatedEvent(
       String project,
       String ref,
-      String sourceNode,
+      URIish sourceUri,
       ReplicationState.RefFetchResult status,
       RefUpdate.Result refUpdateResult) {
-    super(TYPE);
-    this.project = project;
-    this.ref = ref;
-    this.sourceNode = sourceNode;
-    this.status = status.toString();
+    super(TYPE, project, ref, sourceUri, status.toString());
     this.refUpdateResult = refUpdateResult;
   }
 
@@ -63,7 +56,7 @@
     if (!Objects.equals(event.ref, this.ref)) {
       return false;
     }
-    if (!Objects.equals(event.sourceNode, this.sourceNode)) {
+    if (!Objects.equals(event.targetUri, this.targetUri)) {
       return false;
     }
     if (!Objects.equals(event.status, this.status)) {
@@ -81,8 +74,4 @@
   public String getRefName() {
     return ref;
   }
-
-  public String getSourceNode() {
-    return sourceNode;
-  }
 }
diff --git a/src/main/java/com/googlesource/gerrit/plugins/replication/pull/FetchReplicationScheduledEvent.java b/src/main/java/com/googlesource/gerrit/plugins/replication/pull/FetchReplicationScheduledEvent.java
index 9a29c86..4f96a8f 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/replication/pull/FetchReplicationScheduledEvent.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/replication/pull/FetchReplicationScheduledEvent.java
@@ -15,20 +15,14 @@
 package com.googlesource.gerrit.plugins.replication.pull;
 
 import com.google.gerrit.entities.Project;
-import com.google.gerrit.server.events.RefEvent;
+import com.googlesource.gerrit.plugins.replication.events.RemoteRefReplicationEvent;
+import org.eclipse.jgit.transport.URIish;
 
-public class FetchReplicationScheduledEvent extends RefEvent {
+public class FetchReplicationScheduledEvent extends RemoteRefReplicationEvent {
   static final String TYPE = "fetch-ref-replication-scheduled";
 
-  final String project;
-  final String ref;
-  final String sourceNode;
-
-  public FetchReplicationScheduledEvent(String project, String ref, String sourceNode) {
-    super(TYPE);
-    this.project = project;
-    this.ref = ref;
-    this.sourceNode = sourceNode;
+  public FetchReplicationScheduledEvent(String project, String ref, URIish sourceUri) {
+    super(TYPE, project, ref, sourceUri, null);
   }
 
   @Override
@@ -40,8 +34,4 @@
   public Project.NameKey getProjectNameKey() {
     return Project.nameKey(project);
   }
-
-  public String getSourceNode() {
-    return sourceNode;
-  }
 }
diff --git a/src/main/java/com/googlesource/gerrit/plugins/replication/pull/FetchResultProcessing.java b/src/main/java/com/googlesource/gerrit/plugins/replication/pull/FetchResultProcessing.java
index ab16318..eb94ecc 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/replication/pull/FetchResultProcessing.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/replication/pull/FetchResultProcessing.java
@@ -55,7 +55,7 @@
     // Default doing nothing
   }
 
-  public static String resolveNodeName(URIish uri) {
+  private static String resolveNodeName(URIish uri) {
     StringBuilder sb = new StringBuilder();
     if (uri.isRemote()) {
       sb.append(uri.getHost());
@@ -120,8 +120,7 @@
       try {
         Context.setLocalEvent(true);
         dispatcher.postEvent(
-            new FetchRefReplicatedEvent(
-                project, ref, resolveNodeName(uri), status, refUpdateResult));
+            new FetchRefReplicatedEvent(project, ref, uri, status, refUpdateResult));
       } catch (PermissionBackendException e) {
         logger.atSevere().withCause(e).log(
             "Cannot post event for ref '%s', project %s", ref, project);
@@ -189,8 +188,7 @@
         URIish uri,
         ReplicationState.RefFetchResult result,
         RefUpdate.Result refUpdateResult) {
-      postEvent(
-          new FetchRefReplicatedEvent(project, ref, resolveNodeName(uri), result, refUpdateResult));
+      postEvent(new FetchRefReplicatedEvent(project, ref, uri, result, refUpdateResult));
     }
 
     @Override
diff --git a/src/main/java/com/googlesource/gerrit/plugins/replication/pull/Source.java b/src/main/java/com/googlesource/gerrit/plugins/replication/pull/Source.java
index 28aa541..74a4456 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/replication/pull/Source.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/replication/pull/Source.java
@@ -15,7 +15,6 @@
 package com.googlesource.gerrit.plugins.replication.pull;
 
 import static com.googlesource.gerrit.plugins.replication.ReplicationFileBasedConfig.replaceName;
-import static com.googlesource.gerrit.plugins.replication.pull.FetchResultProcessing.resolveNodeName;
 import static com.googlesource.gerrit.plugins.replication.pull.ReplicationType.SYNC;
 
 import com.google.common.base.Throwables;
@@ -793,10 +792,9 @@
   private void postReplicationScheduledEvent(FetchOne fetchOp, String inputRef) {
     Set<String> refs = inputRef == null ? fetchOp.getRefs() : ImmutableSet.of(inputRef);
     Project.NameKey project = fetchOp.getProjectNameKey();
-    String targetNode = resolveNodeName(fetchOp.getURI());
     for (String ref : refs) {
       FetchReplicationScheduledEvent event =
-          new FetchReplicationScheduledEvent(project.get(), ref, targetNode);
+          new FetchReplicationScheduledEvent(project.get(), ref, fetchOp.getURI());
       try {
         eventDispatcher.get().postEvent(BranchNameKey.create(project, ref), event);
       } catch (PermissionBackendException e) {
@@ -807,13 +805,16 @@
 
   private void postReplicationFailedEvent(FetchOne fetchOp, RefUpdate.Result result) {
     Project.NameKey project = fetchOp.getProjectNameKey();
-    String sourceNode = resolveNodeName(fetchOp.getURI());
     try {
       Context.setLocalEvent(true);
       for (String ref : fetchOp.getRefs()) {
         FetchRefReplicatedEvent event =
             new FetchRefReplicatedEvent(
-                project.get(), ref, sourceNode, ReplicationState.RefFetchResult.FAILED, result);
+                project.get(),
+                ref,
+                fetchOp.getURI(),
+                ReplicationState.RefFetchResult.FAILED,
+                result);
         try {
           eventDispatcher.get().postEvent(BranchNameKey.create(project, ref), event);
         } catch (PermissionBackendException e) {
diff --git a/src/main/java/com/googlesource/gerrit/plugins/replication/pull/SourceConfiguration.java b/src/main/java/com/googlesource/gerrit/plugins/replication/pull/SourceConfiguration.java
index ab9c634..aff1266 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/replication/pull/SourceConfiguration.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/replication/pull/SourceConfiguration.java
@@ -211,4 +211,9 @@
   public int getSlowLatencyThreshold() {
     return slowLatencyThreshold;
   }
+
+  @Override
+  public int getPushBatchSize() {
+    return 0;
+  }
 }
diff --git a/src/main/java/com/googlesource/gerrit/plugins/replication/pull/SourcesCollection.java b/src/main/java/com/googlesource/gerrit/plugins/replication/pull/SourcesCollection.java
index 7be4971..53adaaa 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/replication/pull/SourcesCollection.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/replication/pull/SourcesCollection.java
@@ -27,7 +27,11 @@
 import com.googlesource.gerrit.plugins.replication.RemoteConfiguration;
 import com.googlesource.gerrit.plugins.replication.ReplicationConfig;
 import java.util.List;
+import java.util.Map;
 import java.util.Objects;
+import java.util.Optional;
+import java.util.function.Function;
+import java.util.stream.Collectors;
 import org.eclipse.jgit.errors.ConfigInvalidException;
 
 @Singleton
@@ -35,7 +39,7 @@
   private static final FluentLogger logger = FluentLogger.forEnclosingClass();
 
   private final Source.Factory sourceFactory;
-  private volatile List<Source> sources;
+  private volatile Map<String, Source> sources;
   private boolean shuttingDown;
   private final Provider<ReplicationQueue> replicationQueue;
 
@@ -56,22 +60,26 @@
 
   @Override
   public List<Source> getAll() {
-    return sources.stream().filter(Objects::nonNull).collect(toList());
+    return sources.values().stream().filter(Objects::nonNull).collect(toList());
   }
 
-  private List<Source> allSources(
+  public Optional<Source> getByRemoteName(String remoteName) {
+    return Optional.ofNullable(sources.get(remoteName));
+  }
+
+  private Map<String, Source> allSources(
       Source.Factory sourceFactory, List<RemoteConfiguration> sourceConfigurations) {
     return sourceConfigurations.stream()
         .filter((c) -> c instanceof SourceConfiguration)
         .map((c) -> (SourceConfiguration) c)
         .map(sourceFactory::create)
-        .collect(toList());
+        .collect(Collectors.toMap(Source::getRemoteConfigName, Function.identity()));
   }
 
   @Override
   public void startup(WorkQueue workQueue) {
     shuttingDown = false;
-    for (Source cfg : sources) {
+    for (Source cfg : sources.values()) {
       cfg.start(workQueue);
     }
   }
@@ -96,7 +104,7 @@
     }
 
     int discarded = 0;
-    for (Source cfg : sources) {
+    for (Source cfg : sources.values()) {
       discarded += cfg.shutdown();
     }
     return discarded;
diff --git a/src/main/java/com/googlesource/gerrit/plugins/replication/pull/api/ApplyObjectCommand.java b/src/main/java/com/googlesource/gerrit/plugins/replication/pull/api/ApplyObjectCommand.java
index 276aa16..3e6c07b 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/replication/pull/api/ApplyObjectCommand.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/replication/pull/api/ApplyObjectCommand.java
@@ -31,6 +31,8 @@
 import com.googlesource.gerrit.plugins.replication.pull.PullReplicationStateLogger;
 import com.googlesource.gerrit.plugins.replication.pull.ReplicationState;
 import com.googlesource.gerrit.plugins.replication.pull.ReplicationState.RefFetchResult;
+import com.googlesource.gerrit.plugins.replication.pull.Source;
+import com.googlesource.gerrit.plugins.replication.pull.SourcesCollection;
 import com.googlesource.gerrit.plugins.replication.pull.api.data.RevisionData;
 import com.googlesource.gerrit.plugins.replication.pull.api.exception.MissingParentObjectException;
 import com.googlesource.gerrit.plugins.replication.pull.api.exception.RefUpdateException;
@@ -56,17 +58,20 @@
   private final ApplyObject applyObject;
   private final ApplyObjectMetrics metrics;
   private final DynamicItem<EventDispatcher> eventDispatcher;
+  private final SourcesCollection sourcesCollection;
 
   @Inject
   public ApplyObjectCommand(
       PullReplicationStateLogger fetchStateLog,
       ApplyObject applyObject,
       ApplyObjectMetrics metrics,
-      DynamicItem<EventDispatcher> eventDispatcher) {
+      DynamicItem<EventDispatcher> eventDispatcher,
+      SourcesCollection sourcesCollection) {
     this.fetchStateLog = fetchStateLog;
     this.applyObject = applyObject;
     this.metrics = metrics;
     this.eventDispatcher = eventDispatcher;
+    this.sourcesCollection = sourcesCollection;
   }
 
   public void applyObject(
@@ -80,16 +85,23 @@
 
     try {
       Context.setLocalEvent(true);
+      Source source =
+          sourcesCollection
+              .getByRemoteName(sourceLabel)
+              .orElseThrow(
+                  () ->
+                      new IllegalStateException(
+                          String.format("Could not find URI for %s remote", sourceLabel)));
       eventDispatcher
           .get()
           .postEvent(
               new FetchRefReplicatedEvent(
                   name.get(),
                   refName,
-                  sourceLabel,
+                  source.getURI(name),
                   getStatus(refUpdateState),
                   refUpdateState.getResult()));
-    } catch (PermissionBackendException e) {
+    } catch (PermissionBackendException | IllegalStateException e) {
       logger.atSevere().withCause(e).log(
           "Cannot post event for ref '%s', project %s", refName, name);
     } finally {
diff --git a/src/main/java/com/googlesource/gerrit/plugins/replication/pull/api/FetchCommand.java b/src/main/java/com/googlesource/gerrit/plugins/replication/pull/api/FetchCommand.java
index e1ac9ac..8b3c437 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/replication/pull/api/FetchCommand.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/replication/pull/api/FetchCommand.java
@@ -72,8 +72,7 @@
     ReplicationState state =
         fetchReplicationStateFactory.create(
             new FetchResultProcessing.CommandProcessing(this, eventDispatcher.get()));
-    Optional<Source> source =
-        sources.getAll().stream().filter(s -> s.getRemoteConfigName().equals(label)).findFirst();
+    Optional<Source> source = sources.getByRemoteName(label);
     if (!source.isPresent()) {
       String msg = String.format("Remote configuration section %s not found", label);
       fetchStateLog.error(msg, state);
diff --git a/src/test/java/com/googlesource/gerrit/plugins/replication/pull/FetchGitUpdateProcessingTest.java b/src/test/java/com/googlesource/gerrit/plugins/replication/pull/FetchGitUpdateProcessingTest.java
index 77dc947..68044b4 100644
--- a/src/test/java/com/googlesource/gerrit/plugins/replication/pull/FetchGitUpdateProcessingTest.java
+++ b/src/test/java/com/googlesource/gerrit/plugins/replication/pull/FetchGitUpdateProcessingTest.java
@@ -35,6 +35,7 @@
   private GitUpdateProcessing gitUpdateProcessing;
   private CommandProcessing commandProcessing;
   private Command sshCommandMock;
+  private static URIish sourceUri;
 
   @Before
   public void setUp() throws Exception {
@@ -42,6 +43,7 @@
     gitUpdateProcessing = new GitUpdateProcessing(dispatcherMock);
     sshCommandMock = mock(Command.class);
     commandProcessing = new CommandProcessing(sshCommandMock, dispatcherMock);
+    sourceUri = new URIish("git://someHost/someProject.git");
   }
 
   @Test
@@ -51,14 +53,14 @@
         new FetchRefReplicatedEvent(
             "someProject",
             "refs/heads/master",
-            "someHost",
+            sourceUri,
             RefFetchResult.SUCCEEDED,
             RefUpdate.Result.NEW);
 
     gitUpdateProcessing.onOneProjectReplicationDone(
         "someProject",
         "refs/heads/master",
-        new URIish("git://someHost/someProject.git"),
+        sourceUri,
         RefFetchResult.SUCCEEDED,
         RefUpdate.Result.NEW);
     verify(dispatcherMock, times(1)).postEvent(eq(expectedEvent));
@@ -71,7 +73,7 @@
         new FetchRefReplicatedEvent(
             "someProject",
             "refs/heads/master",
-            "someHost",
+            sourceUri,
             RefFetchResult.SUCCEEDED,
             RefUpdate.Result.NEW);
 
@@ -90,7 +92,7 @@
         new FetchRefReplicatedEvent(
             "someProject",
             "refs/changes/01/1/1",
-            "someHost",
+            sourceUri,
             RefFetchResult.FAILED,
             RefUpdate.Result.REJECTED_OTHER_REASON);
 
diff --git a/src/test/java/com/googlesource/gerrit/plugins/replication/pull/api/ApplyObjectCommandTest.java b/src/test/java/com/googlesource/gerrit/plugins/replication/pull/api/ApplyObjectCommandTest.java
index 51051c0..dfd06f8 100644
--- a/src/test/java/com/googlesource/gerrit/plugins/replication/pull/api/ApplyObjectCommandTest.java
+++ b/src/test/java/com/googlesource/gerrit/plugins/replication/pull/api/ApplyObjectCommandTest.java
@@ -31,6 +31,8 @@
 import com.googlesource.gerrit.plugins.replication.pull.ApplyObjectMetrics;
 import com.googlesource.gerrit.plugins.replication.pull.FetchRefReplicatedEvent;
 import com.googlesource.gerrit.plugins.replication.pull.PullReplicationStateLogger;
+import com.googlesource.gerrit.plugins.replication.pull.Source;
+import com.googlesource.gerrit.plugins.replication.pull.SourcesCollection;
 import com.googlesource.gerrit.plugins.replication.pull.api.data.RevisionData;
 import com.googlesource.gerrit.plugins.replication.pull.api.data.RevisionObjectData;
 import com.googlesource.gerrit.plugins.replication.pull.api.exception.MissingParentObjectException;
@@ -38,8 +40,11 @@
 import com.googlesource.gerrit.plugins.replication.pull.fetch.ApplyObject;
 import com.googlesource.gerrit.plugins.replication.pull.fetch.RefUpdateState;
 import java.io.IOException;
+import java.net.URISyntaxException;
+import java.util.Optional;
 import org.eclipse.jgit.lib.Constants;
 import org.eclipse.jgit.lib.RefUpdate;
+import org.eclipse.jgit.transport.URIish;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -54,6 +59,7 @@
   private static final String TEST_REF_NAME = "refs/changes/01/1/1";
   private static final NameKey TEST_PROJECT_NAME = Project.nameKey("test-project");
   private static final String TEST_REMOTE_NAME = "test-remote-name";
+  private static URIish TEST_REMOTE_URI;
 
   @Mock private PullReplicationStateLogger fetchStateLog;
   @Mock private ApplyObject applyObject;
@@ -61,20 +67,26 @@
   @Mock private DynamicItem<EventDispatcher> eventDispatcherDataItem;
   @Mock private EventDispatcher eventDispatcher;
   @Mock private Timer1.Context<String> timetContext;
+  @Mock private SourcesCollection sourceCollection;
+  @Mock private Source source;
   @Captor ArgumentCaptor<Event> eventCaptor;
 
   private ApplyObjectCommand objectUnderTest;
 
   @Before
-  public void setup() throws MissingParentObjectException, IOException {
+  public void setup() throws MissingParentObjectException, IOException, URISyntaxException {
     RefUpdateState state = new RefUpdateState(TEST_REMOTE_NAME, RefUpdate.Result.NEW);
+    TEST_REMOTE_URI = new URIish("git://some.remote.uri");
     when(eventDispatcherDataItem.get()).thenReturn(eventDispatcher);
     when(metrics.start(anyString())).thenReturn(timetContext);
     when(timetContext.stop()).thenReturn(100L);
     when(applyObject.apply(any(), any(), any())).thenReturn(state);
+    when(sourceCollection.getByRemoteName(TEST_SOURCE_LABEL)).thenReturn(Optional.of(source));
+    when(source.getURI(TEST_PROJECT_NAME)).thenReturn(TEST_REMOTE_URI);
 
     objectUnderTest =
-        new ApplyObjectCommand(fetchStateLog, applyObject, metrics, eventDispatcherDataItem);
+        new ApplyObjectCommand(
+            fetchStateLog, applyObject, metrics, eventDispatcherDataItem, sourceCollection);
   }
 
   @Test
@@ -90,6 +102,7 @@
     FetchRefReplicatedEvent fetchEvent = (FetchRefReplicatedEvent) sentEvent;
     assertThat(fetchEvent.getProjectNameKey()).isEqualTo(TEST_PROJECT_NAME);
     assertThat(fetchEvent.getRefName()).isEqualTo(TEST_REF_NAME);
+    assertThat(fetchEvent.targetUri).isEqualTo(TEST_REMOTE_URI.toASCIIString());
   }
 
   private RevisionData createSampleRevisionData() {
diff --git a/src/test/java/com/googlesource/gerrit/plugins/replication/pull/api/FetchCommandTest.java b/src/test/java/com/googlesource/gerrit/plugins/replication/pull/api/FetchCommandTest.java
index e1ad565..e8d1a0f 100644
--- a/src/test/java/com/googlesource/gerrit/plugins/replication/pull/api/FetchCommandTest.java
+++ b/src/test/java/com/googlesource/gerrit/plugins/replication/pull/api/FetchCommandTest.java
@@ -25,7 +25,6 @@
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
-import com.google.common.collect.Lists;
 import com.google.gerrit.entities.Project;
 import com.google.gerrit.extensions.registration.DynamicItem;
 import com.google.gerrit.server.events.EventDispatcher;
@@ -35,6 +34,7 @@
 import com.googlesource.gerrit.plugins.replication.pull.SourcesCollection;
 import com.googlesource.gerrit.plugins.replication.pull.api.exception.RemoteConfigurationMissingException;
 import java.net.URISyntaxException;
+import java.util.Optional;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.Future;
@@ -74,8 +74,7 @@
     label = "instance-1-label";
 
     when(fetchReplicationStateFactory.create(any())).thenReturn(state);
-    when(source.getRemoteConfigName()).thenReturn(label);
-    when(sources.getAll()).thenReturn(Lists.newArrayList(source));
+    when(sources.getByRemoteName(label)).thenReturn(Optional.of(source));
     when(source.schedule(eq(projectName), eq(REF_NAME_TO_FETCH), eq(state), any()))
         .thenReturn(CompletableFuture.completedFuture(null));
     objectUnderTest =
diff --git a/src/test/java/com/googlesource/gerrit/plugins/replication/pull/event/EventsSerializationTest.java b/src/test/java/com/googlesource/gerrit/plugins/replication/pull/event/EventsSerializationTest.java
new file mode 100644
index 0000000..efa521c
--- /dev/null
+++ b/src/test/java/com/googlesource/gerrit/plugins/replication/pull/event/EventsSerializationTest.java
@@ -0,0 +1,83 @@
+// Copyright (C) 2021 The Android Open Source Project
+//
+// Licensed 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.
+
+package com.googlesource.gerrit.plugins.replication.pull.event;
+
+import static com.google.common.truth.Truth.assertThat;
+import static org.junit.Assert.assertTrue;
+
+import com.google.common.base.Objects;
+import com.google.gerrit.server.events.EventGsonProvider;
+import com.google.gson.Gson;
+import com.googlesource.gerrit.plugins.replication.pull.FetchRefReplicatedEvent;
+import com.googlesource.gerrit.plugins.replication.pull.FetchReplicationScheduledEvent;
+import com.googlesource.gerrit.plugins.replication.pull.ReplicationState;
+import org.eclipse.jgit.lib.RefUpdate;
+import org.eclipse.jgit.transport.URIish;
+import org.junit.Before;
+import org.junit.Test;
+
+public class EventsSerializationTest {
+  private static URIish sourceUri;
+  private static final Gson eventGson = new EventGsonProvider().get();
+  private static final String TEST_PROJECT = "test_project";
+  private static final String TEST_REF = "refs/heads/master";
+
+  @Before
+  public void setUp() throws Exception {
+    sourceUri = new URIish(String.format("git://aSourceNode/%s.git", TEST_PROJECT));
+  }
+
+  @Test
+  public void shouldSerializeFetchRefReplicatedEvent() {
+    FetchRefReplicatedEvent origEvent =
+        new FetchRefReplicatedEvent(
+            TEST_PROJECT,
+            TEST_REF,
+            sourceUri,
+            ReplicationState.RefFetchResult.SUCCEEDED,
+            RefUpdate.Result.FAST_FORWARD);
+
+    assertThat(origEvent)
+        .isEqualTo(eventGson.fromJson(eventGson.toJson(origEvent), FetchRefReplicatedEvent.class));
+  }
+
+  @Test
+  public void shouldSerializeFetchReplicationScheduledEvent() {
+    FetchReplicationScheduledEvent origEvent =
+        new FetchReplicationScheduledEvent(TEST_PROJECT, TEST_REF, sourceUri);
+
+    assertTrue(
+        equals(
+            origEvent,
+            eventGson.fromJson(eventGson.toJson(origEvent), FetchReplicationScheduledEvent.class)));
+  }
+
+  private boolean equals(FetchReplicationScheduledEvent scheduledEvent, Object other) {
+    if (!(other instanceof FetchReplicationScheduledEvent)) {
+      return false;
+    }
+    FetchReplicationScheduledEvent event = (FetchReplicationScheduledEvent) other;
+    if (!Objects.equal(event.project, scheduledEvent.project)) {
+      return false;
+    }
+    if (!Objects.equal(event.ref, scheduledEvent.ref)) {
+      return false;
+    }
+    if (!Objects.equal(event.targetUri, scheduledEvent.targetUri)) {
+      return false;
+    }
+    return Objects.equal(event.status, scheduledEvent.status);
+  }
+}
diff --git a/src/test/java/com/googlesource/gerrit/plugins/replication/pull/event/FetchRefReplicatedEventHandlerTest.java b/src/test/java/com/googlesource/gerrit/plugins/replication/pull/event/FetchRefReplicatedEventHandlerTest.java
index e528eca..81a4fc0 100644
--- a/src/test/java/com/googlesource/gerrit/plugins/replication/pull/event/FetchRefReplicatedEventHandlerTest.java
+++ b/src/test/java/com/googlesource/gerrit/plugins/replication/pull/event/FetchRefReplicatedEventHandlerTest.java
@@ -28,17 +28,20 @@
 import com.googlesource.gerrit.plugins.replication.pull.FetchRefReplicatedEvent;
 import com.googlesource.gerrit.plugins.replication.pull.ReplicationState;
 import org.eclipse.jgit.lib.RefUpdate;
+import org.eclipse.jgit.transport.URIish;
 import org.junit.Before;
 import org.junit.Test;
 
 public class FetchRefReplicatedEventHandlerTest {
   private ChangeIndexer changeIndexerMock;
   private FetchRefReplicatedEventHandler fetchRefReplicatedEventHandler;
+  private static URIish sourceUri;
 
   @Before
   public void setUp() throws Exception {
     changeIndexerMock = mock(ChangeIndexer.class);
     fetchRefReplicatedEventHandler = new FetchRefReplicatedEventHandler(changeIndexerMock);
+    sourceUri = new URIish("git://aSourceNode/testProject.git");
   }
 
   @Test
@@ -52,7 +55,7 @@
           new FetchRefReplicatedEvent(
               projectNameKey.get(),
               ref,
-              "aSourceNode",
+              sourceUri,
               ReplicationState.RefFetchResult.SUCCEEDED,
               RefUpdate.Result.FAST_FORWARD));
       verify(changeIndexerMock, times(1)).index(eq(projectNameKey), eq(changeId));
@@ -70,7 +73,7 @@
         new FetchRefReplicatedEvent(
             projectNameKey.get(),
             ref,
-            "aSourceNode",
+            sourceUri,
             ReplicationState.RefFetchResult.SUCCEEDED,
             RefUpdate.Result.FAST_FORWARD));
     verify(changeIndexerMock, never()).index(eq(projectNameKey), eq(changeId));
@@ -85,7 +88,7 @@
         new FetchRefReplicatedEvent(
             projectNameKey.get(),
             ref,
-            "aSourceNode",
+            sourceUri,
             ReplicationState.RefFetchResult.SUCCEEDED,
             RefUpdate.Result.FAST_FORWARD));
     verify(changeIndexerMock, never()).index(eq(projectNameKey), eq(changeId));
@@ -97,7 +100,7 @@
         new FetchRefReplicatedEvent(
             Project.nameKey("testProject").get(),
             "invalidRef",
-            "aSourceNode",
+            sourceUri,
             ReplicationState.RefFetchResult.SUCCEEDED,
             RefUpdate.Result.FAST_FORWARD));
     verify(changeIndexerMock, never()).index(any(), any());
@@ -111,7 +114,7 @@
         new FetchRefReplicatedEvent(
             projectNameKey.get(),
             ref,
-            "aSourceNode",
+            sourceUri,
             ReplicationState.RefFetchResult.FAILED,
             RefUpdate.Result.FAST_FORWARD));
     verify(changeIndexerMock, never()).index(any(), any());
@@ -125,7 +128,7 @@
         new FetchRefReplicatedEvent(
             projectNameKey.get(),
             ref,
-            "aSourceNode",
+            sourceUri,
             ReplicationState.RefFetchResult.NOT_ATTEMPTED,
             RefUpdate.Result.FAST_FORWARD));
     verify(changeIndexerMock, never()).index(any(), any());