1 files changed, 109 insertions, 0 deletions
diff --git a/java/com/google/gerrit/server/restapi/change/Rebuild.java b/java/com/google/gerrit/server/restapi/change/Rebuild.java
new file mode 100644
index 0000000000..dc390ccae3
--- /dev/null
+++ b/java/com/google/gerrit/server/restapi/change/Rebuild.java
@@ -0,0 +1,109 @@
+// Copyright (C) 2016 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.google.gerrit.server.restapi.change;
+
+import static java.util.stream.Collectors.joining;
+
+import com.google.gerrit.extensions.common.Input;
+import com.google.gerrit.extensions.restapi.BinaryResult;
+import com.google.gerrit.extensions.restapi.IdString;
+import com.google.gerrit.extensions.restapi.ResourceConflictException;
+import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
+import com.google.gerrit.reviewdb.server.ReviewDb;
+import com.google.gerrit.reviewdb.server.ReviewDbUtil;
+import com.google.gerrit.server.CommentsUtil;
+import com.google.gerrit.server.change.ChangeResource;
+import com.google.gerrit.server.notedb.ChangeBundle;
+import com.google.gerrit.server.notedb.ChangeBundleReader;
+import com.google.gerrit.server.notedb.ChangeNotes;
+import com.google.gerrit.server.notedb.NotesMigration;
+import com.google.gerrit.server.notedb.rebuild.ChangeRebuilder;
+import com.google.gerrit.server.project.NoSuchChangeException;
+import com.google.gwtorm.server.OrmException;
+import com.google.inject.Inject;
+import com.google.inject.Provider;
+import com.google.inject.Singleton;
+import java.io.IOException;
+import java.util.List;
+import org.eclipse.jgit.errors.ConfigInvalidException;
+
+@Singleton
+public class Rebuild implements RestModifyView<ChangeResource, Input> {
+
+  private final Provider<ReviewDb> db;
+  private final NotesMigration migration;
+  private final ChangeRebuilder rebuilder;
+  private final ChangeBundleReader bundleReader;
+  private final CommentsUtil commentsUtil;
+  private final ChangeNotes.Factory notesFactory;
+
+  @Inject
+  Rebuild(
+      Provider<ReviewDb> db,
+      NotesMigration migration,
+      ChangeRebuilder rebuilder,
+      ChangeBundleReader bundleReader,
+      CommentsUtil commentsUtil,
+      ChangeNotes.Factory notesFactory) {
+    this.db = db;
+    this.migration = migration;
+    this.rebuilder = rebuilder;
+    this.bundleReader = bundleReader;
+    this.commentsUtil = commentsUtil;
+    this.notesFactory = notesFactory;
+  }
+
+  @Override
+  public BinaryResult apply(ChangeResource rsrc, Input input)
+      throws ResourceNotFoundException, IOException, OrmException, ConfigInvalidException,
+          ResourceConflictException {
+    if (!migration.commitChangeWrites()) {
+      throw new ResourceNotFoundException();
+    }
+    if (!migration.readChanges()) {
+      // ChangeBundle#fromNotes currently doesn't work if reading isn't enabled,
+      // so don't attempt a diff.
+      rebuild(rsrc);
+      return BinaryResult.create("Rebuilt change successfully");
+    }
+
+    // Not the same transaction as the rebuild, so may result in spurious diffs
+    // in the case of races. This should be easy enough to detect by rerunning.
+    ChangeBundle reviewDbBundle =
+        bundleReader.fromReviewDb(ReviewDbUtil.unwrapDb(db.get()), rsrc.getId());
+    if (reviewDbBundle == null) {
+      throw new ResourceConflictException("change is missing in ReviewDb");
+    }
+    rebuild(rsrc);
+    ChangeNotes notes = notesFactory.create(db.get(), rsrc.getChange().getProject(), rsrc.getId());
+    ChangeBundle noteDbBundle = ChangeBundle.fromNotes(commentsUtil, notes);
+    List<String> diffs = reviewDbBundle.differencesFrom(noteDbBundle);
+    if (diffs.isEmpty()) {
+      return BinaryResult.create("No differences between ReviewDb and NoteDb");
+    }
+    return BinaryResult.create(
+        diffs.stream().collect(joining("\n", "Differences between ReviewDb and NoteDb:\n", "\n")));
+  }
+
+  private void rebuild(ChangeResource rsrc)
+      throws ResourceNotFoundException, OrmException, IOException {
+    try {
+      rebuilder.rebuild(db.get(), rsrc.getId());
+    } catch (NoSuchChangeException e) {
+      throw new ResourceNotFoundException(IdString.fromDecoded(rsrc.getId().toString()));
+    }
+  }
+}