Add REST endpoint to reindex a single group

This may become handy to fix single groups that are stale in the
index.

Change-Id: Iab3711f343fe1da9bba4979792edc83c76d75a09
Signed-off-by: Edwin Kempin <ekempin@google.com>

gerrit-server/src/main/java/com/google/gerrit/server/api/groups/GroupApiImpl.java

@@ -34,6 +34,7 @@ import com.google.gerrit.server.group.GetName;
 import com.google.gerrit.server.group.GetOptions;
 import com.google.gerrit.server.group.GetOwner;
 import com.google.gerrit.server.group.GroupResource;
+import com.google.gerrit.server.group.Index;
 import com.google.gerrit.server.group.ListIncludedGroups;
 import com.google.gerrit.server.group.ListMembers;
 import com.google.gerrit.server.group.PutDescription;
@@ -71,6 +72,7 @@ class GroupApiImpl implements GroupApi {
   private final DeleteIncludedGroups deleteGroups;
   private final GetAuditLog getAuditLog;
   private final GroupResource rsrc;
+  private final Index index;
 
   @AssistedInject
   GroupApiImpl(
@@ -91,6 +93,7 @@ class GroupApiImpl implements GroupApi {
       AddIncludedGroups addGroups,
       DeleteIncludedGroups deleteGroups,
       GetAuditLog getAuditLog,
+      Index index,
       @Assisted GroupResource rsrc) {
     this.getGroup = getGroup;
     this.getDetail = getDetail;
@@ -109,6 +112,7 @@ class GroupApiImpl implements GroupApi {
     this.addGroups = addGroups;
     this.deleteGroups = deleteGroups;
     this.getAuditLog = getAuditLog;
+    this.index = index;
     this.rsrc = rsrc;
   }
 
@@ -270,4 +274,13 @@ class GroupApiImpl implements GroupApi {
       throw new RestApiException("Cannot get audit log", e);
     }
   }
+
+  @Override
+  public void index() throws RestApiException {
+    try {
+      index.apply(rsrc, new Index.Input());
+    } catch (IOException e) {
+      throw new RestApiException("Cannot index group", e);
+    }
+  }
 }

gerrit-server/src/main/java/com/google/gerrit/server/group/Index.java

@@ -0,0 +1,59 @@
+// 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.group;
+
+import com.google.gerrit.common.data.GroupDescriptions;
+import com.google.gerrit.extensions.restapi.AuthException;
+import com.google.gerrit.extensions.restapi.Response;
+import com.google.gerrit.extensions.restapi.RestModifyView;
+import com.google.gerrit.extensions.restapi.UnprocessableEntityException;
+import com.google.gerrit.reviewdb.client.AccountGroup;
+import com.google.gerrit.server.account.GroupCache;
+import com.google.gerrit.server.group.Index.Input;
+import com.google.inject.Inject;
+import com.google.inject.Singleton;
+
+import java.io.IOException;
+
+@Singleton
+public class Index implements RestModifyView<GroupResource, Input> {
+  public static class Input {
+  }
+
+  private final GroupCache groupCache;
+
+  @Inject
+  Index(GroupCache groupCache) {
+    this.groupCache = groupCache;
+  }
+
+  @Override
+  public Response<?> apply(GroupResource rsrc, Input input)
+      throws IOException, AuthException, UnprocessableEntityException {
+    if (!rsrc.getControl().isOwner()) {
+      throw new AuthException("not allowed to index group");
+    }
+
+    AccountGroup group = GroupDescriptions.toAccountGroup(rsrc.getGroup());
+    if (group == null) {
+      throw new UnprocessableEntityException(String
+          .format("External Group Not Allowed: %s", rsrc.getGroupUUID().get()));
+    }
+
+    // evicting the group from the cache, reindexes the account
+    groupCache.evict(group);
+    return Response.none();
+  }
+}

gerrit-server/src/main/java/com/google/gerrit/server/group/Module.java

@@ -39,6 +39,7 @@ public class Module extends RestApiModule {
     get(GROUP_KIND).to(GetGroup.class);
     put(GROUP_KIND).to(PutGroup.class);
     get(GROUP_KIND, "detail").to(GetDetail.class);
+    post(GROUP_KIND, "index").to(Index.class);
     post(GROUP_KIND, "members").to(AddMembers.class);
     post(GROUP_KIND, "members.add").to(AddMembers.class);
     post(GROUP_KIND, "members.delete").to(DeleteMembers.class);