Expose auto_devops_domain in admin settings view

app/helpers/application_settings_helper.rb

@@ -148,6 +148,7 @@ module ApplicationSettingsHelper
       :akismet_enabled,
       :authorized_keys_enabled,
       :auto_devops_enabled,
+      :auto_devops_domain,
       :circuitbreaker_access_retries,
       :circuitbreaker_check_interval,
       :circuitbreaker_failure_count_threshold,

app/views/admin/application_settings/_form.html.haml

@@ -249,7 +249,12 @@
         .help-block
           It will automatically build, test, and deploy applications based on a predefined CI/CD configuration
           = link_to icon('question-circle'), help_page_path('topics/autodevops/index.md')
-
+    .form-group
+      = f.label :auto_devops_domain, class: 'control-label col-sm-2'
+      .col-sm-10
+        = f.text_field :auto_devops_domain, class: 'form-control', placeholder: 'domain.com'
+        .help-block
+          = s_("Specify a domain to use by default for every project's Auto Review Apps and Auto Deploy stages.")
     .form-group
       .col-sm-offset-2.col-sm-10
         .checkbox

spec/features/admin/admin_settings_spec.rb

@@ -47,6 +47,16 @@ feature 'Admin updates settings' do
     expect(page).to have_content "Application settings saved successfully"
   end
+  scenario 'Change AutoDevOps settings' do
+    check 'Enabled Auto DevOps (Beta) for projects by default'
+    fill_in 'Auto devops domain', with: 'domain.com'
+    click_button 'Save'
+
+    expect(current_application_settings.auto_devops_enabled?).to be true
+    expect(current_application_settings.auto_devops_domain).to eq('domain.com')
+    expect(page).to have_content "Application settings saved successfully"
+  end
+
   scenario 'Change Slack Notifications Service template settings' do
     first(:link, 'Service Templates').click
     click_link 'Slack notifications'