suggested changes that includes:

moving actions for custom domain in its own controller
use separate service class for custom domains
updated help text for custom domains
increased test coverage for custom domains

spec/controllers/admin/conference_domains_controller_spec.rb

@@ -0,0 +1,42 @@
+require 'spec_helper'
+
+describe Admin::ConferenceDomainsController do
+  let!(:admin) { create(:admin) }
+  let!(:conference) { create(:conference) }
+  context 'as signed in admin' do
+    before do
+      sign_in admin
+    end
+
+    describe 'GET #show' do
+      it 'redirects to edit if custom domain is not present' do
+        get :show, conference_id: conference.short_title
+        expect(response).to redirect_to(admin_conference_conference_domains_edit_path)
+      end
+
+      it 'renders correct template if custom domain is present' do
+        conference.update_attribute(:custom_domain, 'mydomain.conf')
+        get :show, conference_id: conference.short_title
+        expect(response).to render_template('show')
+      end
+    end
+
+    describe 'PATCH #update' do
+      before do
+        patch :update, conference_id: conference.short_title,
+                       conference: { custom_domain: 'newdomain.conf' }
+      end
+
+      it 'successfully updates the custom domain' do
+        expect(conference.reload.custom_domain).to eq('newdomain.conf')
+      end
+    end
+
+    describe 'GET #edit' do
+      it 'renders correct template' do
+        get :edit, conference_id: conference.short_title
+        expect(response).to render_template('edit')
+      end
+    end
+  end
+end

spec/controllers/admin/conferences_controller_spec.rb

@@ -135,15 +135,6 @@ describe Admin::ConferencesController do
         end
       end
     end
-
-    describe 'GET #custom_domain', blah: true do
-      it 'render custom domain' do
-        get :custom_domain, id: conference.short_title
-
-        expect(response).to render_template :custom_domain
-        expect(response).to be_success
-      end
-    end
   end
 
   shared_examples 'access as organization_admin' do

spec/features/conference_domains_spec.rb

@@ -0,0 +1,87 @@
+require 'spec_helper'
+
+feature Conference do
+  let!(:organization) { create(:organization) }
+  let!(:conference) { create(:conference, custom_domain: 'mydomain.conf', organization: organization) }
+  let(:admin) { create(:admin) }
+  let(:role_organization_admin) { Role.find_by(name: 'organization_admin', resource: organization) }
+  let(:user_organization_admin) { create(:user, role_ids: [role_organization_admin.id]) }
+  let(:role_organizer) { Role.find_by(name: 'organizer', resource: conference) }
+  let(:user_organizer) { create(:user, role_ids: [role_organizer.id]) }
+  let(:role_info_desk) { Role.find_by(name: 'info_desk', resource: conference) }
+  let(:user_info_desk) { create(:user, role_ids: [role_info_desk.id]) }
+  let(:role_cfp) { Role.find_by(name: 'cfp', resource: conference) }
+  let(:user_cfp) { create(:user, role_ids: [role_cfp.id]) }
+
+  shared_examples 'successfully adds, update or show custom domain' do
+    scenario 'adds or update custom domain of a conference', feature: true, js: true do
+      visit admin_conference_conference_domains_edit_path(conference.short_title)
+
+      fill_in 'conference_custom_domain', with: 'newdomain.conf'
+      click_button 'Attach this domain'
+
+      expect(flash).to eq 'Attached new domain name to conference. This does not mean that the new domain should work. Please make sure you follow step 3 to point your domain to this hosted version'
+      expect(page).to have_text('newdomain.conf')
+    end
+
+    scenario 'show custom domain of a conference', feature: true, js: true do
+      visit admin_conference_conference_domain_path(conference.short_title)
+
+      expect(page).to have_text('mydomain.conf')
+    end
+  end
+
+  shared_examples 'does not add, update or show custom domain' do
+    scenario 'does not add or update custom domain', feature: true, js: true do
+      visit admin_conference_conference_domains_edit_path(conference.short_title)
+
+      expect(flash).to eq 'You are not authorized to access this page.'
+    end
+
+    scenario 'does not show custom domain of a conference', feature: true, js: true do
+      visit admin_conference_conference_domain_path(conference.short_title)
+
+      expect(flash).to eq 'You are not authorized to access this page.'
+    end
+  end
+
+  context 'signed in as admin' do
+    before do
+      sign_in admin
+    end
+
+    it_behaves_like 'successfully adds, update or show custom domain'
+  end
+
+  context 'signed in as organization admin' do
+    before do
+      sign_in user_organization_admin
+    end
+
+    it_behaves_like 'successfully adds, update or show custom domain'
+  end
+
+  context 'signed in as organizer' do
+    before do
+      sign_in user_organizer
+    end
+
+    it_behaves_like 'successfully adds, update or show custom domain'
+  end
+
+  context 'signed in as info_desk' do
+    before do
+      sign_in user_info_desk
+    end
+
+    it_behaves_like 'does not add, update or show custom domain'
+  end
+
+  context 'signed in as cfp' do
+    before do
+      sign_in user_cfp
+    end
+
+    it_behaves_like 'does not add, update or show custom domain'
+  end
+end

spec/features/conference_spec.rb

@@ -68,15 +68,6 @@ feature Conference do
       expect(conference.short_title).to eq('NewCon')
       expect(Conference.count).to eq(expected_count)
     end
-
-    scenario 'show custom domain of a conference', feature: true, js: true do
-      conference = create(:conference, custom_domain: 'mydomain.conf')
-      sign_in user
-
-      visit custom_domain_admin_conference_path(conference.short_title)
-
-      expect(page).to have_text('mydomain.conf')
-    end
   end
 
   describe 'admin' do