Refactor StagesController with abstract controller

This MR makes sure we do not leak pipeline actions to our
controller by inheriting from our new abstract controller.

app/controllers/projects/pipelines/stages_controller.rb

+# frozen_string_literal: true
+
+module Projects
+  module Pipelines
+    class StagesController < Projects::Pipelines::ApplicationController
+      before_action :authorize_update_pipeline!
+
+      def play_manual
+        ::Ci::PlayManualStageService
+          .new(@project, current_user, pipeline: pipeline)
+          .execute(stage)
+
+        respond_to do |format|
+          format.json do
+            render json: StageSerializer
+              .new(project: @project, current_user: @current_user)
+              .represent(stage)
+          end
+        end
+      end
+
+      private
+
+      def stage
+        @pipeline_stage ||= pipeline.find_stage_by_name!(params[:stage_name])
+      end
+    end
+  end
+end

app/controllers/projects/stages_controller.rb

-# frozen_string_literal: true
-
-class Projects::StagesController < Projects::PipelinesController
-  before_action :authorize_update_pipeline!
-
-  def play_manual
-    ::Ci::PlayManualStageService
-      .new(@project, current_user, pipeline: pipeline)
-      .execute(stage)
-
-    respond_to do |format|
-      format.json do
-        render json: StageSerializer
-          .new(project: @project, current_user: @current_user)
-          .represent(stage)
-      end
-    end
-  end
-
-  private
-
-  def stage
-    @pipeline_stage ||= pipeline.find_stage_by_name!(params[:stage_name])
-  end
-end

config/routes/pipelines.rb

@@ -22,10 +22,8 @@ resources :pipelines, only: [:index, :new, :create, :show, :destroy] do
     get :test_reports_count
   end
 
-  member do
-    resources :stages, only: [], param: :name do
-      post :play_manual
-    end
+  resources :stages, only: [], param: :name, controller: 'pipelines/stages' do
+    post :play_manual
   end
 
   resources :tests, only: [:show], param: :suite_name, controller: 'pipelines/tests' do

lib/gitlab/ci/status/stage/play_manual.rb

@@ -18,7 +18,7 @@ module Gitlab
           def action_path
             pipeline = subject.pipeline
 
-            project_stage_play_manual_path(pipeline.project, pipeline, subject.name)
+            project_pipeline_stage_play_manual_path(pipeline.project, pipeline, subject.name)
           end
 
           def action_method

spec/controllers/projects/stages_controller_spec.rb → spec/controllers/projects/pipelines/stages_controller_spec.rb

@@ -2,7 +2,7 @@
 
 require 'spec_helper'
 
-RSpec.describe Projects::StagesController do
+RSpec.describe Projects::Pipelines::StagesController do
   let(:user) { create(:user) }
   let(:project) { create(:project, :repository) }
 
@@ -60,7 +60,7 @@ RSpec.describe Projects::StagesController do
       post :play_manual, params: {
         namespace_id: project.namespace,
         project_id: project,
-        id: pipeline.id,
+        pipeline_id: pipeline.id,
         stage_name: stage_name
       }, format: :json
     end