refactor: show system-enrollment-error page if 500 during linking

benefits/enrollment/views.py

@@ -28,6 +28,7 @@
 
 TEMPLATE_RETRY = "enrollment/retry.html"
 TEMPLATE_SUCCESS = "enrollment/success.html"
+TEMPLATE_SYSTEM_ERROR = "enrollment/system_error.html"
 
 
 logger = logging.getLogger(__name__)
@@ -91,6 +92,9 @@ def index(request):
             if e.response.status_code == 409:
                 analytics.returned_success(request, eligibility.group_id)
                 return success(request)
+            elif e.response.status_code >= 500:
+                analytics.returned_error(request, str(e))
+                return system_error(request)
             else:
                 analytics.returned_error(request, str(e))
                 raise Exception(f"{e}: {e.response.json()}")
@@ -129,6 +133,12 @@ def retry(request):
     return TemplateResponse(request, TEMPLATE_RETRY)
 
 
+@decorator_from_middleware(EligibleSessionRequired)
+def system_error(request):
+    """View handler for an enrollment system error."""
+    return TemplateResponse(request, TEMPLATE_SYSTEM_ERROR)
+
+
 @pageview_decorator
 @decorator_from_middleware(VerifierSessionRequired)
 def success(request):

tests/pytest/enrollment/test_views.py

@@ -14,6 +14,7 @@
     ROUTE_SUCCESS,
     ROUTE_RETRY,
     TEMPLATE_SUCCESS,
+    TEMPLATE_SYSTEM_ERROR,
     TEMPLATE_RETRY,
 )
 
@@ -126,12 +127,36 @@ def test_index_eligible_post_invalid_form(client, invalid_form_data):
 
 
 @pytest.mark.django_db
+@pytest.mark.parametrize("status_code", [500, 501, 502, 503, 504])
 @pytest.mark.usefixtures("mocked_session_agency", "mocked_session_eligibility")
-def test_index_eligible_post_valid_form_http_error(mocker, client, card_tokenize_form_data):
+def test_index_eligible_post_valid_form_http_error_500(
+    mocker, client, mocked_analytics_module, card_tokenize_form_data, status_code
+):
+    mock_client_cls = mocker.patch("benefits.enrollment.views.Client")
+    mock_client = mock_client_cls.return_value
+
+    mock_error = {"message": "Mock error message"}
+    mock_error_response = mocker.Mock(status_code=status_code, **mock_error)
+    mock_error_response.json.return_value = mock_error
+    mock_client.link_concession_group_funding_source.side_effect = HTTPError(
+        response=mock_error_response,
+    )
+
+    path = reverse(ROUTE_INDEX)
+    response = client.post(path, card_tokenize_form_data)
+
+    assert response.status_code == 200
+    assert response.template_name == TEMPLATE_SYSTEM_ERROR
+    mocked_analytics_module.returned_error.assert_called_once()
+
+
+@pytest.mark.django_db
+@pytest.mark.usefixtures("mocked_session_agency", "mocked_session_eligibility")
+def test_index_eligible_post_valid_form_http_error_400(mocker, client, card_tokenize_form_data):
     mock_client_cls = mocker.patch("benefits.enrollment.views.Client")
     mock_client = mock_client_cls.return_value
 
-    # any status_code that isn't 409 is considered an error
+    # any 400 level status_code that isn't 409 is considered an error
     mock_error = {"message": "Mock error message"}
     mock_error_response = mocker.Mock(status_code=400, **mock_error)
     mock_error_response.json.return_value = mock_error