Load js app data in controller

This change request is a continuation of a conversation started in
https://gitlab.com/gitlab-org/gitlab/-/merge_requests/22465/diffs.

It extracts the data that is loaded for the client side application in
the controller so that each piece of data that is loaded can be tested.

ee/app/controllers/projects/licenses_controller.rb

@@ -8,6 +8,7 @@ module Projects
     def index
       respond_to do |format|
         format.html do
+          @licenses_app_data = licenses_app_data
           render status: :ok
         end
         format.json do
@@ -80,5 +81,13 @@ module Projects
     def truthy?(value)
       value.in?(%w[true 1])
     end
+
+    def licenses_app_data
+      {
+        endpoint: project_licenses_path(project, detected: true, format: :json),
+        documentation_path: help_page_path('user/application_security/license_compliance/index'),
+        empty_state_svg_path: helpers.image_path('illustrations/Dependency-list-empty-state.svg')
+      }
+    end
   end
 end

ee/app/views/projects/licenses/index.html.haml

 - breadcrumb_title _('License Compliance')
 - page_title _('License Compliance')
 
-#js-licenses-app{ data: { endpoint: project_licenses_path(@project, detected: true, format: :json),
-  documentation_path: help_page_path('user/application_security/license_compliance/index'),
-  empty_state_svg_path: image_path('illustrations/Dependency-list-empty-state.svg') } }
+#js-licenses-app{ data: licenses_app_data }

ee/spec/controllers/projects/licenses_controller_spec.rb

@@ -27,6 +27,10 @@ describe Projects::LicensesController do
           get :index, params: params
 
           expect(response).to have_gitlab_http_status(:ok)
+          licenses_app_data = assigns(:licenses_app_data)
+          expect(licenses_app_data[:endpoint]).to eql(controller.helpers.project_licenses_path(project, detected: true, format: :json))
+          expect(licenses_app_data[:documentation_path]).to eql(help_page_path('user/application_security/license_compliance/index'))
+          expect(licenses_app_data[:empty_state_svg_path]).to eql(controller.helpers.image_path('illustrations/Dependency-list-empty-state.svg'))
         end
 
         it 'counts usage of the feature' do