Re-create global-refdb project versions when missing

Do not fail if the global-refdb project versions are missing and
create them again as brand-new entries, using the local version as
initial value.

Bug: Issue 12393
Change-Id: Ie772ef59eb3e602e42d8e775d85a3a8206c963fa

src/main/java/com/googlesource/gerrit/plugins/multisite/validation/ProjectVersionRefUpdate.java

diff --git a/src/main/java/com/googlesource/gerrit/plugins/multisite/validation/ProjectVersionRefUpdate.java b/src/main/java/com/googlesource/gerrit/plugins/multisite/validation/ProjectVersionRefUpdate.java
index 84965c0..a8f344e 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/multisite/validation/ProjectVersionRefUpdate.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/multisite/validation/ProjectVersionRefUpdate.java
@@ -200,15 +200,24 @@
             "Updating shared project version for %s. Current value %s, new value: %s",
             projectNameKey.get(), currentRef.getObjectId(), newObjectId));
     try {
+      if (!sharedRefDb.exists(projectNameKey, MULTI_SITE_VERSIONING_REF)) {
+        currentRef =
+            new ObjectIdRef.Unpeeled(Ref.Storage.NEW, MULTI_SITE_VERSIONING_REF, ObjectId.zeroId());
+      }
+      if (!sharedRefDb.exists(projectNameKey, MULTI_SITE_VERSIONING_VALUE_REF)) {
+        currentVersion = Optional.empty();
+      }
+
       boolean success = sharedRefDb.compareAndPut(projectNameKey, currentRef, newObjectId);
       if (!success) {
         String message =
             String.format(
                 "Project version blob update failed for %s. Current value %s, new value: %s",
-                projectNameKey.get(), currentRef.getObjectId(), newObjectId);
+                projectNameKey.get(), safeGetObjectId(currentRef), newObjectId);
         logger.atSevere().log(message);
         throw new SharedProjectVersionUpdateException(message);
       }
+
       success =
           sharedRefDb.compareAndPut(
               projectNameKey,
@@ -219,7 +228,7 @@
         String message =
             String.format(
                 "Project version update failed for %s. Current value %s, new value: %s",
-                projectNameKey.get(), currentRef.getObjectId(), newObjectId);
+                projectNameKey.get(), safeGetObjectId(currentRef), newObjectId);
         logger.atSevere().log(message);
         throw new SharedProjectVersionUpdateException(message);
       }
@@ -260,6 +269,10 @@
     return globalVersion.flatMap(longString -> getLongValueOf(longString));
   }
 
+  private Object safeGetObjectId(Ref currentRef) {
+    return currentRef == null ? "null" : currentRef.getObjectId();
+  }
+
   private Optional<Long> getLongValueOf(String longString) {
     try {
       return Optional.ofNullable(Long.parseLong(longString));

src/test/java/com/googlesource/gerrit/plugins/multisite/validation/ProjectVersionRefUpdateTest.java

diff --git a/src/test/java/com/googlesource/gerrit/plugins/multisite/validation/ProjectVersionRefUpdateTest.java b/src/test/java/com/googlesource/gerrit/plugins/multisite/validation/ProjectVersionRefUpdateTest.java
index 16dd545..da8c8a9 100644
--- a/src/test/java/com/googlesource/gerrit/plugins/multisite/validation/ProjectVersionRefUpdateTest.java
+++ b/src/test/java/com/googlesource/gerrit/plugins/multisite/validation/ProjectVersionRefUpdateTest.java
@@ -18,6 +18,7 @@
 import static com.googlesource.gerrit.plugins.multisite.validation.ProjectVersionRefUpdate.MULTI_SITE_VERSIONING_REF;
 import static com.googlesource.gerrit.plugins.multisite.validation.ProjectVersionRefUpdate.MULTI_SITE_VERSIONING_VALUE_REF;
 import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.isNull;
 import static org.mockito.Mockito.atMost;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.verifyZeroInteractions;
@@ -87,8 +88,16 @@
   @Test
   public void producerShouldUpdateProjectVersionUponRefUpdatedEvent() throws IOException {
     Context.setForwardedEvent(false);
+    when(sharedRefDb.exists(
+            A_TEST_PROJECT_NAME_KEY, ProjectVersionRefUpdate.MULTI_SITE_VERSIONING_REF))
+        .thenReturn(true);
+    when(sharedRefDb.exists(
+            A_TEST_PROJECT_NAME_KEY, ProjectVersionRefUpdate.MULTI_SITE_VERSIONING_VALUE_REF))
+        .thenReturn(true);
     when(sharedRefDb.compareAndPut(any(Project.NameKey.class), any(Ref.class), any(ObjectId.class)))
         .thenReturn(true);
+    when(sharedRefDb.compareAndPut(any(Project.NameKey.class), any(String.class), any(), any()))
+        .thenReturn(true);
     when(refUpdatedEvent.getProjectNameKey()).thenReturn(A_TEST_PROJECT_NAME_KEY);
     when(refUpdatedEvent.getRefName()).thenReturn(A_TEST_REF_NAME);
 
@@ -110,6 +119,41 @@
   }
 
   @Test
+  public void producerShouldCreateNewProjectVersionWhenMissingUponRefUpdatedEvent()
+      throws IOException {
+    Context.setForwardedEvent(false);
+    when(sharedRefDb.exists(
+            A_TEST_PROJECT_NAME_KEY, ProjectVersionRefUpdate.MULTI_SITE_VERSIONING_REF))
+        .thenReturn(false);
+    when(sharedRefDb.exists(
+            A_TEST_PROJECT_NAME_KEY, ProjectVersionRefUpdate.MULTI_SITE_VERSIONING_VALUE_REF))
+        .thenReturn(false);
+
+    when(sharedRefDb.compareAndPut(any(Project.NameKey.class), isNull(), any(ObjectId.class)))
+        .thenReturn(true);
+    when(sharedRefDb.compareAndPut(any(Project.NameKey.class), any(String.class), any(), any()))
+        .thenReturn(true);
+    when(refUpdatedEvent.getProjectNameKey()).thenReturn(A_TEST_PROJECT_NAME_KEY);
+    when(refUpdatedEvent.getRefName()).thenReturn(A_TEST_REF_NAME);
+
+    new ProjectVersionRefUpdate(repoManager, sharedRefDb, gitReferenceUpdated, verLogger)
+        .onEvent(refUpdatedEvent);
+
+    Ref ref = repo.getRepository().findRef(MULTI_SITE_VERSIONING_REF);
+
+    verify(sharedRefDb, atMost(1))
+        .compareAndPut(any(Project.NameKey.class), isNull(), any(ObjectId.class));
+
+    assertThat(ref).isNotNull();
+
+    ObjectLoader loader = repo.getRepository().open(ref.getObjectId());
+    String storedVersion = IOUtils.toString(loader.openStream(), StandardCharsets.UTF_8.name());
+    assertThat(Long.parseLong(storedVersion)).isEqualTo(masterCommit.getCommitTime());
+
+    verify(verLogger).log(A_TEST_PROJECT_NAME_KEY, masterCommit.getCommitTime(), 0);
+  }
+
+  @Test
   public void producerShouldNotUpdateProjectVersionUponSequenceRefUpdatedEvent() throws Exception {
     producerShouldNotUpdateProjectVersionUponMagicRefUpdatedEvent(RefNames.REFS_SEQUENCES);
   }