Add REST endpoint to get a label definition of a project

Bug: Issue 11522
Signed-off-by: Edwin Kempin <ekempin@google.com>
Change-Id: I41e5c015d6067653c5794595df5ba7b97ca679a3

java/com/google/gerrit/server/api/projects/LabelApiImpl.java

@@ -0,0 +1,49 @@
+// 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.server.api.projects;
+
+import static com.google.gerrit.server.api.ApiUtil.asRestApiException;
+
+import com.google.gerrit.extensions.api.projects.LabelApi;
+import com.google.gerrit.extensions.common.LabelDefinitionInfo;
+import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.server.project.LabelResource;
+import com.google.gerrit.server.restapi.project.GetLabel;
+import com.google.inject.Inject;
+import com.google.inject.assistedinject.Assisted;
+
+public class LabelApiImpl implements LabelApi {
+  interface Factory {
+    LabelApiImpl create(LabelResource rsrc);
+  }
+
+  private final GetLabel getLabel;
+  private final LabelResource rsrc;
+
+  @Inject
+  LabelApiImpl(GetLabel getLabel, @Assisted LabelResource rsrc) {
+    this.getLabel = getLabel;
+    this.rsrc = rsrc;
+  }
+
+  @Override
+  public LabelDefinitionInfo get() throws RestApiException {
+    try {
+      return getLabel.apply(rsrc).value();
+    } catch (Exception e) {
+      throw asRestApiException("Cannot get label", e);
+    }
+  }
+}

java/com/google/gerrit/server/api/projects/Module.java

@@ -28,5 +28,6 @@ public class Module extends FactoryModule {
     factory(ChildProjectApiImpl.Factory.class);
     factory(CommitApiImpl.Factory.class);
     factory(DashboardApiImpl.Factory.class);
+    factory(LabelApiImpl.Factory.class);
   }
 }

java/com/google/gerrit/server/api/projects/ProjectApiImpl.java

@@ -37,6 +37,7 @@ import com.google.gerrit.extensions.api.projects.DeleteTagsInput;
 import com.google.gerrit.extensions.api.projects.DescriptionInput;
 import com.google.gerrit.extensions.api.projects.HeadInput;
 import com.google.gerrit.extensions.api.projects.IndexProjectInput;
+import com.google.gerrit.extensions.api.projects.LabelApi;
 import com.google.gerrit.extensions.api.projects.ParentInput;
 import com.google.gerrit.extensions.api.projects.ProjectApi;
 import com.google.gerrit.extensions.api.projects.ProjectInput;
@@ -72,6 +73,7 @@ import com.google.gerrit.server.restapi.project.GetHead;
 import com.google.gerrit.server.restapi.project.GetParent;
 import com.google.gerrit.server.restapi.project.Index;
 import com.google.gerrit.server.restapi.project.IndexChanges;
+import com.google.gerrit.server.restapi.project.LabelsCollection;
 import com.google.gerrit.server.restapi.project.ListBranches;
 import com.google.gerrit.server.restapi.project.ListDashboards;
 import com.google.gerrit.server.restapi.project.ListLabels;
@@ -130,6 +132,8 @@ public class ProjectApiImpl implements ProjectApi {
   private final Index index;
   private final IndexChanges indexChanges;
   private final Provider<ListLabels> listLabels;
+  private final LabelsCollection labels;
+  private final LabelApiImpl.Factory labelApi;
 
   @AssistedInject
   ProjectApiImpl(
@@ -166,6 +170,8 @@ public class ProjectApiImpl implements ProjectApi {
       Index index,
       IndexChanges indexChanges,
       Provider<ListLabels> listLabels,
+      LabelApiImpl.Factory labelApi,
+      LabelsCollection labels,
       @Assisted ProjectResource project) {
     this(
         permissionBackend,
@@ -202,6 +208,8 @@ public class ProjectApiImpl implements ProjectApi {
         index,
         indexChanges,
         listLabels,
+        labelApi,
+        labels,
         null);
   }
 
@@ -240,6 +248,8 @@ public class ProjectApiImpl implements ProjectApi {
       Index index,
       IndexChanges indexChanges,
       Provider<ListLabels> listLabels,
+      LabelApiImpl.Factory labelApi,
+      LabelsCollection labels,
       @Assisted String name) {
     this(
         permissionBackend,
@@ -276,6 +286,8 @@ public class ProjectApiImpl implements ProjectApi {
         index,
         indexChanges,
         listLabels,
+        labelApi,
+        labels,
         name);
   }
 
@@ -314,6 +326,8 @@ public class ProjectApiImpl implements ProjectApi {
       Index index,
       IndexChanges indexChanges,
       Provider<ListLabels> listLabels,
+      LabelApiImpl.Factory labelApi,
+      LabelsCollection labels,
       String name) {
     this.permissionBackend = permissionBackend;
     this.createProject = createProject;
@@ -350,6 +364,8 @@ public class ProjectApiImpl implements ProjectApi {
     this.index = index;
     this.indexChanges = indexChanges;
     this.listLabels = listLabels;
+    this.labelApi = labelApi;
+    this.labels = labels;
   }
 
   @Override
@@ -695,4 +711,13 @@ public class ProjectApiImpl implements ProjectApi {
       }
     };
   }
+
+  @Override
+  public LabelApi label(String labelName) throws RestApiException {
+    try {
+      return labelApi.create(labels.parse(checkExists(), IdString.fromDecoded(labelName)));
+    } catch (Exception e) {
+      throw asRestApiException("Cannot parse label", e);
+    }
+  }
 }