Validate feature availability in the Boards::CreateService

app/controllers/ee/projects/boards_controller.rb

@@ -9,7 +9,7 @@ module EE
       end
 
       def create
-        board = ::Boards::CreateService.new(project, current_user, board_params).execute
+        board = EE::Boards::CreateService.new(project, current_user, board_params).execute
 
         respond_to do |format|
           format.json do

app/services/boards/create_service.rb

 module Boards
   class CreateService < BaseService
     def execute
-      board = project.boards.create(params)
-
-      if board.persisted?
-        board.lists.create(list_type: :backlog)
-        board.lists.create(list_type: :closed)
+      if project.boards.empty?
+        create_board!
+      else
+        project.boards.first
       end
+    end
+
+    private
+
+    def create_board!
+      board = project.boards.create
+      board.lists.create(list_type: :backlog)
+      board.lists.create(list_type: :closed)
 
       board
     end

app/services/ee/boards/create_service.rb

+module EE
+  module Boards
+    class CreateService < BaseService
+      def execute
+        return nil unless can_create_board?
+
+        board = project.boards.create(params)
+
+        if board.persisted?
+          board.lists.create(list_type: :backlog)
+          board.lists.create(list_type: :closed)
+        end
+
+        board
+      end
+
+      def can_create_board?
+        project.feature_available?(:multiple_issue_boards) || project.boards.size < 1
+      end
+    end
+  end
+end

spec/services/boards/create_service_spec.rb

@@ -4,11 +4,11 @@ describe Boards::CreateService, services: true do
   describe '#execute' do
     let(:project) { create(:empty_project) }
 
-    context 'with valid params' do
-      subject(:service) { described_class.new(project, double, name: 'Backend') }
+    subject(:service) { described_class.new(project, double) }
 
-      it 'creates a new project board' do
-        expect { service.execute }.to change(project.boards, :count).by(1)
+    context 'when project does not have a board' do
+      it 'creates a new board' do
+        expect { service.execute }.to change(Board, :count).by(1)
       end
 
       it 'creates the default lists' do
@@ -20,32 +20,13 @@ describe Boards::CreateService, services: true do
       end
     end
 
-    context 'with invalid params' do
-      subject(:service) { described_class.new(project, double, name: nil) }
-
-      it 'does not create a new project board' do
-        expect { service.execute }.not_to change(project.boards, :count)
-      end
-
-      it "does not create board's default lists" do
-        board = service.execute
-
-        expect(board.lists.size).to eq 0
+    context 'when project has a board' do
+      before do
+        create(:board, project: project)
       end
-    end
-
-    context 'without params' do
-      subject(:service) { described_class.new(project, double) }
 
-      it 'creates a new project board' do
-        expect { service.execute }.to change(project.boards, :count).by(1)
-      end
-
-      it "creates board's default lists" do
-        board = service.execute
-
-        expect(board.lists.size).to eq 2
-        expect(board.lists.last).to be_closed
+      it 'does not create a new board' do
+        expect { service.execute }.not_to change(project.boards, :count)
       end
     end
   end

spec/services/ee/boards/create_service_spec.rb

+require 'spec_helper'
+
+describe EE::Boards::CreateService, services: true do
+  describe '#execute' do
+    let(:project) { create(:empty_project) }
+
+    context 'With the feature available' do
+      before do
+        stub_licensed_features(multiple_issue_boards: true)
+      end
+
+      context 'with valid params' do
+        subject(:service) { described_class.new(project, double, name: 'Backend') }
+
+        it 'creates a new project board' do
+          expect { service.execute }.to change(project.boards, :count).by(1)
+        end
+
+        it 'creates the default lists' do
+          board = service.execute
+
+          expect(board.lists.size).to eq 2
+          expect(board.lists.first).to be_backlog
+          expect(board.lists.last).to be_closed
+        end
+      end
+
+      context 'with invalid params' do
+        subject(:service) { described_class.new(project, double, name: nil) }
+
+        it 'does not create a new project board' do
+          expect { service.execute }.not_to change(project.boards, :count)
+        end
+
+        it "does not create board's default lists" do
+          board = service.execute
+
+          expect(board.lists.size).to eq 0
+        end
+      end
+
+      context 'without params' do
+        subject(:service) { described_class.new(project, double) }
+
+        it 'creates a new project board' do
+          expect { service.execute }.to change(project.boards, :count).by(1)
+        end
+
+        it "creates board's default lists" do
+          board = service.execute
+
+          expect(board.lists.size).to eq 2
+          expect(board.lists.last).to be_closed
+        end
+      end
+    end
+
+    it 'skips creating a second board when the feature is not available' do
+      stub_licensed_features(multiple_issue_boards: false)
+      service = described_class.new(project, double)
+
+      expect(service.execute).not_to be_nil
+
+      expect { service.execute }.not_to change(project.boards, :count)
+    end
+  end
+end