login: add an option to hide cancel button (#41122)

src/authentic2/app_settings.py

@@ -311,6 +311,10 @@ default_settings = dict(
     A2_LOGIN_REDIRECT_AUTHENTICATED_USERS_TO_HOMEPAGE=Setting(
         default=False,
         definition='Redirect authenticated users to homepage'),
+    A2_LOGIN_DISPLAY_A_CANCEL_BUTTON=Setting(
+        default=False,
+        definition='Display a cancel button.'
+        'This is only applicable for Liberty single sign on requests'),
     A2_SET_RANDOM_PASSWORD_ON_RESET=Setting(
         default=True,
         definition='Set a random password on request to reset the password from the front-office'),

src/authentic2/views.py

@@ -278,7 +278,7 @@ def login(request, template_name='authentic2/login.html',
     registration_url = utils.get_registration_url(request, service=service)
 
     context = {
-        'cancel': nonce is not None,
+        'cancel': app_settings.A2_LOGIN_DISPLAY_A_CANCEL_BUTTON and nonce is not None,
         'can_reset_password': app_settings.A2_USER_CAN_RESET_PASSWORD is not False,
         'registration_authorized': getattr(settings, 'REGISTRATION_OPEN', True),
         'registration_url': registration_url,

tests/test_idp_saml2.py

@@ -52,6 +52,7 @@ from . import utils
 @pytest.fixture
 def saml_settings(settings):
     settings.A2_IDP_SAML2_ENABLE = True
+    settings.A2_LOGIN_DISPLAY_A_CANCEL_BUTTON = True
 
 
 def get_idp_metadata(app):

tests/test_views.py

@@ -236,3 +236,12 @@ def test_views_email_token_resend(app, simple_user, settings, mailoutbox, view_n
     # validating again anyway works
     response = response.form.submit()
     assert len(mailoutbox) == 2
+
+
+def test_views_login_display_a_cancel_button(app, settings):
+    response = app.get(reverse('auth_login'), params={'next': '/foo/', 'nonce': 'xxx'})
+    assert not response.html.find('button', {'class': 'cancel-button'})
+
+    settings.A2_LOGIN_DISPLAY_A_CANCEL_BUTTON = True
+    response = app.get(reverse('auth_login'), params={'next': '/foo/', 'nonce': 'xxx'})
+    assert response.html.find('button', {'class': 'cancel-button'})