Introduce top-menu APIs

Expose the ability to invoke the list of top-menu items provided by
plugins through the GerritApi.

Main use-case is enabling the automation of tests that need to verify
the top-menu items configuration.

Change-Id: Ic2f5b6c9dc07e9695a75f07372d11c5e6d731761
diff --git a/java/com/google/gerrit/extensions/api/config/Server.java b/java/com/google/gerrit/extensions/api/config/Server.java
index 5ec63af..70d1bff 100644
--- a/java/com/google/gerrit/extensions/api/config/Server.java
+++ b/java/com/google/gerrit/extensions/api/config/Server.java
@@ -20,6 +20,8 @@
 import com.google.gerrit.extensions.common.ServerInfo;
 import com.google.gerrit.extensions.restapi.NotImplementedException;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.webui.TopMenu;
+import java.util.List;
 
 public interface Server {
   /** @return Version of server. */
@@ -41,6 +43,8 @@
 
   ConsistencyCheckInfo checkConsistency(ConsistencyCheckInput in) throws RestApiException;
 
+  List<TopMenu.MenuEntry> topMenus() throws RestApiException;
+
   /**
    * A default implementation which allows source compatibility when adding new methods to the
    * interface.
@@ -93,5 +97,10 @@
     public ConsistencyCheckInfo checkConsistency(ConsistencyCheckInput in) throws RestApiException {
       throw new NotImplementedException();
     }
+
+    @Override
+    public List<TopMenu.MenuEntry> topMenus() throws RestApiException {
+      throw new NotImplementedException();
+    }
   }
 }
diff --git a/java/com/google/gerrit/server/api/config/ServerImpl.java b/java/com/google/gerrit/server/api/config/ServerImpl.java
index ec08507..6e78be2 100644
--- a/java/com/google/gerrit/server/api/config/ServerImpl.java
+++ b/java/com/google/gerrit/server/api/config/ServerImpl.java
@@ -25,18 +25,21 @@
 import com.google.gerrit.extensions.client.GeneralPreferencesInfo;
 import com.google.gerrit.extensions.common.ServerInfo;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.webui.TopMenu;
 import com.google.gerrit.server.config.ConfigResource;
 import com.google.gerrit.server.restapi.config.CheckConsistency;
 import com.google.gerrit.server.restapi.config.GetDiffPreferences;
 import com.google.gerrit.server.restapi.config.GetEditPreferences;
 import com.google.gerrit.server.restapi.config.GetPreferences;
 import com.google.gerrit.server.restapi.config.GetServerInfo;
+import com.google.gerrit.server.restapi.config.ListTopMenus;
 import com.google.gerrit.server.restapi.config.SetDiffPreferences;
 import com.google.gerrit.server.restapi.config.SetEditPreferences;
 import com.google.gerrit.server.restapi.config.SetPreferences;
 import com.google.inject.Inject;
 import com.google.inject.Provider;
 import com.google.inject.Singleton;
+import java.util.List;
 
 @Singleton
 public class ServerImpl implements Server {
@@ -48,6 +51,7 @@
   private final SetEditPreferences setEditPreferences;
   private final GetServerInfo getServerInfo;
   private final Provider<CheckConsistency> checkConsistency;
+  private final ListTopMenus listTopMenus;
 
   @Inject
   ServerImpl(
@@ -58,7 +62,8 @@
       GetEditPreferences getEditPreferences,
       SetEditPreferences setEditPreferences,
       GetServerInfo getServerInfo,
-      Provider<CheckConsistency> checkConsistency) {
+      Provider<CheckConsistency> checkConsistency,
+      ListTopMenus listTopMenus) {
     this.getPreferences = getPreferences;
     this.setPreferences = setPreferences;
     this.getDiffPreferences = getDiffPreferences;
@@ -67,6 +72,7 @@
     this.setEditPreferences = setEditPreferences;
     this.getServerInfo = getServerInfo;
     this.checkConsistency = checkConsistency;
+    this.listTopMenus = listTopMenus;
   }
 
   @Override
@@ -148,4 +154,9 @@
       throw asRestApiException("Cannot check consistency", e);
     }
   }
+
+  @Override
+  public List<TopMenu.MenuEntry> topMenus() {
+    return listTopMenus.apply(new ConfigResource()).value();
+  }
 }
diff --git a/javatests/com/google/gerrit/acceptance/api/config/TopMenusIT.java b/javatests/com/google/gerrit/acceptance/api/config/TopMenusIT.java
new file mode 100644
index 0000000..b6d2712
--- /dev/null
+++ b/javatests/com/google/gerrit/acceptance/api/config/TopMenusIT.java
@@ -0,0 +1,60 @@
+// Copyright (C) 2019 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.acceptance.api.config;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import com.google.gerrit.acceptance.LightweightPluginDaemonTest;
+import com.google.gerrit.acceptance.TestPlugin;
+import com.google.gerrit.extensions.registration.DynamicSet;
+import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.webui.TopMenu;
+import com.google.gerrit.extensions.webui.TopMenu.MenuEntry;
+import com.google.inject.AbstractModule;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+import org.junit.Test;
+
+@TestPlugin(
+    name = "test-topmenus",
+    sysModule = "com.google.gerrit.acceptance.api.config.TopMenusIT$Module")
+public class TopMenusIT extends LightweightPluginDaemonTest {
+
+  static final TopMenu.MenuEntry TEST_MENU_ENTRY =
+      new TopMenu.MenuEntry("MyMenu", Collections.emptyList());
+
+  public static class Module extends AbstractModule {
+
+    @Override
+    protected void configure() {
+      DynamicSet.bind(binder(), TopMenu.class).to(TopMenuTest.class);
+    }
+  }
+
+  public static class TopMenuTest implements TopMenu {
+
+    @Override
+    public List<MenuEntry> getEntries() {
+      return Arrays.asList(TEST_MENU_ENTRY);
+    }
+  }
+
+  @Test
+  public void topMenuShouldReturnOneEntry() throws RestApiException {
+    List<MenuEntry> topMenuItems = gApi.config().server().topMenus();
+    assertThat(topMenuItems).containsExactly(TEST_MENU_ENTRY);
+  }
+}