Delete user branch when account is deleted

Change-Id: I4fde3560c5d5f138a19f69b695d881fc4b3ce337
Signed-off-by: Edwin Kempin <ekempin@google.com>

gerrit-acceptance-tests/src/test/java/com/google/gerrit/acceptance/server/change/ConsistencyCheckerIT.java

@@ -41,6 +41,7 @@ import com.google.gerrit.reviewdb.client.RefNames;
 import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.IdentifiedUser;
 import com.google.gerrit.server.Sequences;
+import com.google.gerrit.server.account.AccountsUpdate;
 import com.google.gerrit.server.change.ChangeInserter;
 import com.google.gerrit.server.change.ConsistencyChecker;
 import com.google.gerrit.server.change.PatchSetInserter;
@@ -90,6 +91,8 @@ public class ConsistencyCheckerIT extends AbstractDaemonTest {
 
   @Inject private Sequences sequences;
 
+  @Inject private AccountsUpdate.Server accountsUpdate;
+
   private RevCommit tip;
   private Account.Id adminId;
   private ConsistencyChecker checker;
@@ -119,7 +122,7 @@ public class ConsistencyCheckerIT extends AbstractDaemonTest {
   public void missingOwner() throws Exception {
     TestAccount owner = accounts.create("missing");
     ChangeControl ctl = insertChange(owner);
-    db.accounts().deleteKeys(singleton(owner.getId()));
+    accountsUpdate.create().deleteByKey(db, owner.getId());
 
     assertProblems(ctl, null, problem("Missing change owner: " + owner.getId()));
   }

gerrit-server/src/main/java/com/google/gerrit/server/account/AccountManager.java

@@ -232,12 +232,13 @@ public class AccountManager {
         awaitsFirstAccountCheck.getAndSet(false) && db.accounts().anyAccounts().toList().isEmpty();
 
     try {
-      accountsUpdateFactory.create().upsert(db, account);
+      AccountsUpdate accountsUpdate = accountsUpdateFactory.create();
+      accountsUpdate.upsert(db, account);
 
       ExternalId existingExtId = externalIds.get(db, extId.key());
       if (existingExtId != null && !existingExtId.accountId().equals(extId.accountId())) {
         // external ID is assigned to another account, do not overwrite
-        db.accounts().delete(Collections.singleton(account));
+        accountsUpdate.delete(db, account);
         throw new AccountException(
             "Cannot assign external ID \""
                 + extId.key().get()
@@ -345,7 +346,7 @@ public class AccountManager {
       // such an account cannot be used for uploading changes,
       // this is why the best we can do here is to fail early and cleanup
       // the database
-      db.accounts().delete(Collections.singleton(account));
+      accountsUpdateFactory.create().delete(db, account);
       externalIdsUpdateFactory.create().delete(db, extId);
       throw new AccountUserNameException(errorMessage, e);
     }

gerrit-server/src/main/java/com/google/gerrit/server/account/AccountsUpdate.java

@@ -36,6 +36,7 @@ import org.eclipse.jgit.lib.Constants;
 import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.lib.ObjectInserter;
 import org.eclipse.jgit.lib.PersonIdent;
+import org.eclipse.jgit.lib.Ref;
 import org.eclipse.jgit.lib.RefUpdate;
 import org.eclipse.jgit.lib.RefUpdate.Result;
 import org.eclipse.jgit.lib.Repository;
@@ -144,6 +145,18 @@ public class AccountsUpdate {
     createUserBranchIfNeeded(account);
   }
 
+  /** Deletes the account. */
+  public void delete(ReviewDb db, Account account) throws OrmException, IOException {
+    db.accounts().delete(ImmutableSet.of(account));
+    deleteUserBranch(account.getId());
+  }
+
+  /** Deletes the account. */
+  public void deleteByKey(ReviewDb db, Account.Id accountId) throws OrmException, IOException {
+    db.accounts().deleteKeys(ImmutableSet.of(accountId));
+    deleteUserBranch(accountId);
+  }
+
   private void createUserBranch(Account account) throws IOException {
     try (Repository repo = repoManager.openRepository(allUsersName);
         ObjectInserter oi = repo.newObjectInserter()) {
@@ -209,4 +222,25 @@ public class AccountsUpdate {
   private static ObjectId emptyTree(ObjectInserter oi) throws IOException {
     return oi.insert(Constants.OBJ_TREE, new byte[] {});
   }
+
+  private void deleteUserBranch(Account.Id accountId) throws IOException {
+    try (Repository repo = repoManager.openRepository(allUsersName)) {
+      String refName = RefNames.refsUsers(accountId);
+      Ref ref = repo.exactRef(refName);
+      if (ref == null) {
+        return;
+      }
+
+      RefUpdate ru = repo.updateRef(refName);
+      ru.setExpectedOldObjectId(ref.getObjectId());
+      ru.setNewObjectId(ObjectId.zeroId());
+      ru.setForceUpdate(true);
+      ru.setRefLogIdent(committerIdent);
+      ru.setRefLogMessage("Delete Account", true);
+      Result result = ru.delete();
+      if (result != Result.FORCED) {
+        throw new IOException(String.format("Failed to delete ref %s: %s", refName, result.name()));
+      }
+    }
+  }
 }