Add migration to make account IDs of all external IDs human-readable

External IDs are stored as Git config files in NoteDb. To set the
account ID in the config we used Config#setInt(...), but this method
persists integers that can be expressed in KiB as a unit string, e.g.
"1024000" is stored as "100k". Human readers will be confused by such
account IDs. This is why writing account IDs for new external IDs was
fixed by change I6838d69d. This change adds a schema migration to also
fix all existing external IDs with this problem.

Change-Id: Idbe4cb76cc5fc66e55026185d801d037f3ae4550
Signed-off-by: Edwin Kempin <ekempin@google.com>

gerrit-server/src/main/java/com/google/gerrit/server/schema/SchemaVersion.java

@@ -35,7 +35,7 @@ import java.util.concurrent.TimeUnit;
 /** A version of the database schema. */
 public abstract class SchemaVersion {
   /** The current schema version. */
-  public static final Class<Schema_147> C = Schema_147.class;
+  public static final Class<Schema_148> C = Schema_148.class;
 
   public static int getBinaryVersion() {
     return guessVersion(C);

gerrit-server/src/main/java/com/google/gerrit/server/schema/Schema_148.java

@@ -0,0 +1,99 @@
+// Copyright (C) 2017 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.schema;
+
+import static org.eclipse.jgit.lib.Constants.OBJ_BLOB;
+
+import com.google.common.primitives.Ints;
+import com.google.gerrit.reviewdb.server.ReviewDb;
+import com.google.gerrit.server.GerritPersonIdent;
+import com.google.gerrit.server.account.externalids.ExternalId;
+import com.google.gerrit.server.account.externalids.ExternalIdReader;
+import com.google.gerrit.server.account.externalids.ExternalIdsUpdate;
+import com.google.gerrit.server.config.AllUsersName;
+import com.google.gerrit.server.git.GitRepositoryManager;
+import com.google.gwtorm.server.OrmException;
+import com.google.inject.Inject;
+import com.google.inject.Provider;
+import java.io.IOException;
+import java.sql.SQLException;
+import org.eclipse.jgit.errors.ConfigInvalidException;
+import org.eclipse.jgit.lib.Config;
+import org.eclipse.jgit.lib.ObjectId;
+import org.eclipse.jgit.lib.ObjectInserter;
+import org.eclipse.jgit.lib.PersonIdent;
+import org.eclipse.jgit.lib.Repository;
+import org.eclipse.jgit.notes.Note;
+import org.eclipse.jgit.notes.NoteMap;
+import org.eclipse.jgit.revwalk.RevWalk;
+
+public class Schema_148 extends SchemaVersion {
+  private static final String COMMIT_MSG = "Make account IDs of external IDs human-readable";
+
+  private final GitRepositoryManager repoManager;
+  private final AllUsersName allUsersName;
+  private final PersonIdent serverUser;
+
+  @Inject
+  Schema_148(
+      Provider<Schema_147> prior,
+      GitRepositoryManager repoManager,
+      AllUsersName allUsersName,
+      @GerritPersonIdent PersonIdent serverUser) {
+    super(prior);
+    this.repoManager = repoManager;
+    this.allUsersName = allUsersName;
+    this.serverUser = serverUser;
+  }
+
+  @Override
+  protected void migrateData(ReviewDb db, UpdateUI ui) throws OrmException, SQLException {
+    try (Repository repo = repoManager.openRepository(allUsersName);
+        RevWalk rw = new RevWalk(repo);
+        ObjectInserter ins = repo.newObjectInserter()) {
+      ObjectId rev = ExternalIdReader.readRevision(repo);
+      NoteMap noteMap = ExternalIdReader.readNoteMap(rw, rev);
+      boolean dirty = false;
+      for (Note note : noteMap) {
+        byte[] raw =
+            rw.getObjectReader()
+                .open(note.getData(), OBJ_BLOB)
+                .getCachedBytes(ExternalIdReader.MAX_NOTE_SZ);
+        try {
+          ExternalId extId = ExternalId.parse(note.getName(), raw);
+
+          if (needsUpdate(extId)) {
+            ExternalIdsUpdate.upsert(rw, ins, noteMap, extId);
+            dirty = true;
+          }
+        } catch (ConfigInvalidException e) {
+          ui.message(
+              String.format("Warning: Ignoring invalid external ID note %s", note.getName()));
+        }
+      }
+      if (dirty) {
+        ExternalIdsUpdate.commit(repo, rw, ins, rev, noteMap, COMMIT_MSG, serverUser, serverUser);
+      }
+    } catch (IOException e) {
+      throw new OrmException("Failed to update external IDs", e);
+    }
+  }
+
+  private static boolean needsUpdate(ExternalId extId) {
+    Config cfg = new Config();
+    cfg.setInt("externalId", extId.key().get(), "accountId", extId.accountId().get());
+    return Ints.tryParse(cfg.getString("externalId", extId.key().get(), "accountId")) == null;
+  }
+}