Merge pull request #1439 from alphagov/dvla-endpoint

Add platform–admin-only page to preview DVLA code

app/main/views/templates.py

@@ -9,12 +9,14 @@ from flask import (
     flash,
     abort,
     json,
+    Response,
 )
 from flask_login import login_required, current_user
 from dateutil.parser import parse
 
 from notifications_utils.formatters import escape_html
 from notifications_utils.recipients import first_column_headings
+from notifications_utils.template import LetterDVLATemplate
 from notifications_python_client.errors import HTTPError
 
 from app.main import main
@@ -146,6 +148,25 @@ def choose_template(service_id, template_type='all'):
     )
 
 
+@main.route("/services/<service_id>/templates/<template_id>/as-dvla")
+@login_required
+@user_has_permissions(admin_override=True)
+def view_template_as_dvla_markup(service_id, template_id):
+
+    template = service_api_client.get_service_template(service_id, str(template_id))['data']
+
+    if template['template_type'] != 'letter':
+        abort(404)
+
+    return Response(
+        str(LetterDVLATemplate(
+            template,
+            notification_reference=1,
+        )).replace('<cr>', '<cr>\n'),
+        mimetype='text/plain',
+    )
+
+
 @main.route("/services/<service_id>/templates/<template_id>.<filetype>")
 @login_required
 @user_has_permissions('view_activity', admin_override=True)

tests/app/main/views/test_templates.py

@@ -14,6 +14,9 @@ from tests.conftest import (
     mock_get_service_template,
     normalize_spaces,
     SERVICE_ONE_ID,
+    active_user_with_permissions,
+    platform_admin_user,
+    mock_get_user,
 )
 from tests import validate_route_permission, template_json, single_notification_json
 
@@ -1163,3 +1166,48 @@ def test_should_show_hint_once_template_redacted(
     )
 
     assert page.select('.hint')[0].text == 'Personalisation is hidden after sending'
+
+
+@pytest.mark.parametrize('test_user, template_mock, expected_response_code', [
+    (
+        active_user_with_permissions,
+        mock_get_service_letter_template,
+        403
+    ),
+    (
+        platform_admin_user,
+        mock_get_service_template,
+        404
+    ),
+    (
+        platform_admin_user,
+        mock_get_service_email_template,
+        404
+    ),
+    (
+        platform_admin_user,
+        mock_get_service_letter_template,
+        200
+    ),
+])
+def test_should_show_letter_template_as_dvla_markup(
+    client,
+    mocker,
+    service_one,
+    fake_uuid,
+    mock_get_service,
+    test_user,
+    template_mock,
+    expected_response_code,
+):
+
+    client.login(test_user(fake_uuid), mocker, service_one)
+    template_mock(mocker)
+
+    response = client.get(url_for(
+        '.view_template_as_dvla_markup',
+        service_id=SERVICE_ONE_ID,
+        template_id=fake_uuid,
+    ))
+
+    assert response.status_code == expected_response_code