Add license check for the 'send emails from Admin area' feature

This change adds license check for the
'send emails from Admin area' feature.

ee/app/controllers/admin/emails_controller.rb

 # frozen_string_literal: true
 
 class Admin::EmailsController < Admin::ApplicationController
+  include Admin::EmailsHelper
+
+  before_action :check_license_send_emails_from_admin_area_available!
+
   def show
   end
 
@@ -8,4 +12,10 @@ class Admin::EmailsController < Admin::ApplicationController
     AdminEmailsWorker.perform_async(params[:recipients], params[:subject], params[:body]) # rubocop:disable CodeReuse/Worker
     redirect_to admin_email_path, notice: 'Email sent'
   end
+
+  private
+
+  def check_license_send_emails_from_admin_area_available!
+    render_404 unless send_emails_from_admin_area_feature_available?
+  end
 end

ee/app/helpers/admin/emails_helper.rb

+# frozen_string_literal: true
+
+module Admin
+  module EmailsHelper
+    def send_emails_from_admin_area_feature_available?
+      License.feature_available?(:send_emails_from_admin_area)
+    end
+  end
+end

ee/app/models/license.rb

@@ -36,6 +36,7 @@ class License < ApplicationRecord
     repository_mirrors
     repository_size_limit
     seat_link
+    send_emails_from_admin_area
     service_desk
     scoped_issue_board
     usage_quotas

ee/app/views/admin/users/_admin_email_users.html.haml

+- return unless send_emails_from_admin_area_feature_available?
+
 = link_to s_('AdminUsers|Send email to users'), admin_email_path, class: 'btn'

ee/changelogs/unreleased/license-check-for-admin-email-blast.yml

+---
+title: Add license check for the 'send emails from Admin area' feature
+merge_request: 31434
+author:
+type: fixed

ee/spec/controllers/admin/emails_controller_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Admin::EmailsController do
+  let_it_be(:admin) { create(:admin) }
+  let_it_be(:user) { create(:user) }
+
+  describe 'GET #show' do
+    subject { get :show }
+
+    context 'admin user' do
+      before do
+        sign_in(admin)
+      end
+
+      context 'when `send_emails_from_admin_area` feature is enabled' do
+        before do
+          stub_licensed_features(send_emails_from_admin_area: true)
+        end
+
+        it 'responds with 200' do
+          subject
+
+          expect(response).to have_gitlab_http_status(:ok)
+        end
+      end
+
+      context 'when `send_emails_from_admin_area` feature is disabled' do
+        before do
+          stub_licensed_features(send_emails_from_admin_area: false)
+        end
+
+        it 'returns 404' do
+          subject
+
+          expect(response).to have_gitlab_http_status(:not_found)
+        end
+      end
+    end
+
+    context 'non-admin user' do
+      before do
+        sign_in(user)
+      end
+
+      it 'returns 404' do
+        subject
+
+        expect(response).to have_gitlab_http_status(:not_found)
+      end
+    end
+  end
+
+  describe 'POST #create' do
+    subject do
+      post :create, params: {
+        recipients: 'all',
+        subject: 'subject',
+        body: 'body'
+      }
+    end
+
+    context 'admin user' do
+      before do
+        sign_in(admin)
+      end
+
+      context 'when `send_emails_from_admin_area` feature is enabled' do
+        before do
+          stub_licensed_features(send_emails_from_admin_area: true)
+        end
+
+        it 'trigger the background job to send emails' do
+          expect(AdminEmailsWorker).to receive(:perform_async).with('all', 'subject', 'body')
+
+          subject
+        end
+
+        it 'redirects to `admin_email_path`' do
+          subject
+
+          expect(response).to have_gitlab_http_status(:found)
+          expect(response).to redirect_to(admin_email_path)
+          expect(flash[:notice]).to eq('Email sent')
+        end
+      end
+
+      context 'when `send_emails_from_admin_area` feature is disabled' do
+        before do
+          stub_licensed_features(send_emails_from_admin_area: false)
+        end
+
+        it 'does not trigger the background job to send emails' do
+          expect(AdminEmailsWorker).not_to receive(:perform_async)
+
+          subject
+        end
+
+        it 'returns 404' do
+          subject
+
+          expect(response).to have_gitlab_http_status(:not_found)
+        end
+      end
+    end
+
+    context 'non-admin user' do
+      before do
+        sign_in(user)
+      end
+
+      it 'returns 404' do
+        subject
+
+        expect(response).to have_gitlab_http_status(:not_found)
+      end
+    end
+  end
+end

ee/spec/features/admin/admin_users_spec.rb

@@ -15,6 +15,34 @@ describe "Admin::Users" do
     sign_in(current_user)
   end
 
+  describe 'GET /admin/users' do
+    describe 'send emails to users' do
+      context 'when `send_emails_from_admin_area` feature is enabled' do
+        before do
+          stub_licensed_features(send_emails_from_admin_area: true)
+        end
+
+        it "shows the 'Send email to users' link" do
+          visit admin_users_path
+
+          expect(page).to have_link('Send email to users', href: admin_email_path)
+        end
+      end
+
+      context 'when `send_emails_from_admin_area` feature is disabled' do
+        before do
+          stub_licensed_features(send_emails_from_admin_area: false)
+        end
+
+        it "does not show the 'Send email to users' link" do
+          visit admin_users_path
+
+          expect(page).not_to have_link('Send email to users', href: admin_email_path)
+        end
+      end
+    end
+  end
+
   describe "GET /admin/users/:id" do
     describe 'Shared runners quota status' do
       before do

ee/spec/helpers/admin/emails_helper_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Admin::EmailsHelper do
+  describe '#send_emails_from_admin_area_feature_available?' do
+    subject { helper.send_emails_from_admin_area_feature_available? }
+
+    context 'when `send_emails_from_admin_area` feature is enabled' do
+      before do
+        stub_licensed_features(send_emails_from_admin_area: true)
+      end
+
+      it { is_expected.to be_truthy }
+    end
+
+    context 'when `send_emails_from_admin_area` feature is disabled' do
+      before do
+        stub_licensed_features(send_emails_from_admin_area: false)
+      end
+
+      it { is_expected.to be_falsey }
+    end
+  end
+end