Add e2e QA test for logging in using GitHub OAuth

Adds the test itself and the vendor page object model for GitHub
login pages.

app/helpers/auth_helper.rb

@@ -16,6 +16,13 @@ module AuthHelper
     PROVIDERS_WITH_ICONS.include?(name.to_s)
   end
 
+  def qa_class_for_provider(provider)
+    {
+      saml: 'qa-saml-login-button',
+      github: 'qa-github-login-button'
+    }[provider.to_sym]
+  end
+
   def auth_providers
     Gitlab::Auth::OAuth::Provider.providers
   end

app/views/devise/shared/_omniauth_box.html.haml

@@ -5,7 +5,7 @@
   .d-flex.justify-content-between.flex-wrap
     - providers.each do |provider|
       - has_icon = provider_has_icon?(provider)
-      = link_to omniauth_authorize_path(:user, provider), method: :post, class: 'btn d-flex align-items-center omniauth-btn text-left oauth-login qa-saml-login-button', id: "oauth-login-#{provider}" do
+      = link_to omniauth_authorize_path(:user, provider), method: :post, class: "btn d-flex align-items-center omniauth-btn text-left oauth-login #{qa_class_for_provider(provider)}", id: "oauth-login-#{provider}" do
         - if has_icon
           = provider_image_tag(provider)
         %span

qa/qa.rb

@@ -99,6 +99,7 @@ module QA
         autoload :LDAPNoTLS, 'qa/scenario/test/integration/ldap_no_tls'
         autoload :LDAPTLS, 'qa/scenario/test/integration/ldap_tls'
         autoload :InstanceSAML, 'qa/scenario/test/integration/instance_saml'
+        autoload :OAuth, 'qa/scenario/test/integration/oauth'
         autoload :Kubernetes, 'qa/scenario/test/integration/kubernetes'
         autoload :Mattermost, 'qa/scenario/test/integration/mattermost'
         autoload :ObjectStorage, 'qa/scenario/test/integration/object_storage'
@@ -342,6 +343,13 @@ module QA
         autoload :Login, 'qa/vendor/saml_idp/page/login'
       end
     end
+
+    module Github
+      module Page
+        autoload :Base, 'qa/vendor/github/page/base'
+        autoload :Login, 'qa/vendor/github/page/login'
+      end
+    end
   end
 
   # Classes that provide support to other parts of the framework.

qa/qa/page/main/login.rb

@@ -31,8 +31,9 @@ module QA
           element :register_tab
         end
 
-        view 'app/views/devise/shared/_omniauth_box.html.haml' do
+        view 'app/helpers/auth_helper.rb' do
           element :saml_login_button
+          element :github_login_button
         end
 
         view 'app/views/layouts/devise.html.haml' do
@@ -149,13 +150,18 @@ module QA
           click_element :standard_tab
         end
 
-        private
+        def sign_in_with_github
+          set_initial_password_if_present
+          click_element :github_login_button
+        end
 
         def sign_in_with_saml
           set_initial_password_if_present
           click_element :saml_login_button
         end
 
+        private
+
         def sign_in_using_gitlab_credentials(user)
           switch_to_sign_in_tab if has_sign_in_tab?
           switch_to_standard_tab if has_standard_tab?

qa/qa/runtime/env.rb

@@ -102,6 +102,14 @@ module QA
         ENV['GITLAB_ADMIN_PASSWORD']
       end
 
+      def github_username
+        ENV['GITHUB_USERNAME']
+      end
+
+      def github_password
+        ENV['GITHUB_PASSWORD']
+      end
+
       def forker?
         !!(forker_username && forker_password)
       end

qa/qa/scenario/test/integration/oauth.rb

+# frozen_string_literal: true
+
+module QA
+  module Scenario
+    module Test
+      module Integration
+        class OAuth < Test::Instance::All
+          tags :oauth
+        end
+      end
+    end
+  end
+end

qa/qa/specs/features/browser_ui/1_manage/login/login_via_oauth_spec.rb

+# frozen_string_literal: true
+
+module QA
+  context 'Manage', :orchestrated, :oauth do
+    describe 'OAuth login' do
+      it 'User logs in to GitLab with GitHub OAuth' do
+        Runtime::Browser.visit(:gitlab, Page::Main::Login)
+
+        Page::Main::Login.perform(&:sign_in_with_github)
+        Vendor::Github::Page::Login.perform(&:login)
+
+        expect(page).to have_content('Welcome to GitLab')
+      end
+    end
+  end
+end

qa/qa/vendor/github/page/base.rb

+# frozen_string_literal: true
+
+module QA
+  module Vendor
+    module Github
+      module Page
+        class Base
+          include Capybara::DSL
+          include Scenario::Actable
+        end
+      end
+    end
+  end
+end

qa/qa/vendor/github/page/login.rb

+# frozen_string_literal: true
+
+require 'capybara/dsl'
+
+module QA
+  module Vendor
+    module Github
+      module Page
+        class Login < Page::Base
+          def login
+            fill_in 'login', with: QA::Runtime::Env.github_username
+            fill_in 'password', with: QA::Runtime::Env.github_password
+            click_on 'Sign in'
+
+            unless has_no_text?("Authorize GitLab-OAuth")
+              click_on 'Authorize gitlab-qa' if has_button?('Authorize gitlab-qa')
+            end
+          end
+        end
+      end
+    end
+  end
+end

qa/spec/scenario/test/integration/oauth_spec.rb

+# frozen_string_literal: true
+
+describe QA::Scenario::Test::Integration::OAuth do
+  context '#perform' do
+    it_behaves_like 'a QA scenario class' do
+      let(:tags) { [:oauth] }
+    end
+  end
+end