refs #134 -- check callback configuration at startup/app loading

Author: brunobord

demo/tests/test_post_save_callbacks.py

@@ -2,12 +2,15 @@
 from __future__ import unicode_literals
 
 from copy import deepcopy
+from django.core.exceptions import ImproperlyConfigured
 from django.core.urlresolvers import reverse
-from django.test import override_settings
+from django.conf import settings
+from django.test import TestCase, override_settings
 
 from rest_framework.test import APITestCase
 
 from formidable.models import Formidable
+from formidable.views import check_callback_configuration
 
 from . import form_data, form_data_items
 
@@ -173,3 +176,60 @@ def test_update_callback_is_non_existent(self):
             )
             self.assertEqual(res.status_code, 200)
             self.assertEqual(logger_error.call_count, 1)
+
+
+class ConfigurationLoadingTestCases(TestCase):
+
+    @override_settings()
+    def test_all_deleted(self):
+        del settings.FORMIDABLE_POST_UPDATE_CALLBACK_SUCCESS
+        del settings.FORMIDABLE_POST_UPDATE_CALLBACK_FAIL
+        del settings.FORMIDABLE_POST_CREATE_CALLBACK_SUCCESS
+        del settings.FORMIDABLE_POST_CREATE_CALLBACK_FAIL
+        self.assertTrue(check_callback_configuration())
+
+    @override_settings(
+        FORMIDABLE_POST_UPDATE_CALLBACK_SUCCESS=None,
+        FORMIDABLE_POST_UPDATE_CALLBACK_FAIL=None,
+        FORMIDABLE_POST_CREATE_CALLBACK_SUCCESS=None,
+        FORMIDABLE_POST_CREATE_CALLBACK_FAIL=None
+    )
+    def test_all_none(self):
+        self.assertTrue(check_callback_configuration())
+
+    @override_settings(
+        FORMIDABLE_POST_UPDATE_CALLBACK_SUCCESS='',
+        FORMIDABLE_POST_UPDATE_CALLBACK_FAIL='',
+        FORMIDABLE_POST_CREATE_CALLBACK_SUCCESS='',
+        FORMIDABLE_POST_CREATE_CALLBACK_FAIL=''
+    )
+    def test_all_empty(self):
+        self.assertTrue(check_callback_configuration())
+
+    @override_settings(
+        FORMIDABLE_POST_UPDATE_CALLBACK_SUCCESS='non.existing',
+    )
+    def test_update_success_unknown(self):
+        with self.assertRaises(ImproperlyConfigured):
+            check_callback_configuration()
+
+    @override_settings(
+        FORMIDABLE_POST_UPDATE_CALLBACK_FAIL='non.existing',
+    )
+    def test_update_fail_unknown(self):
+        with self.assertRaises(ImproperlyConfigured):
+            check_callback_configuration()
+
+    @override_settings(
+        FORMIDABLE_POST_CREATE_CALLBACK_SUCCESS='non.existing',
+    )
+    def test_create_success_unknown(self):
+        with self.assertRaises(ImproperlyConfigured):
+            check_callback_configuration()
+
+    @override_settings(
+        FORMIDABLE_POST_CREATE_CALLBACK_FAIL='non.existing',
+    )
+    def test_create_fail_unknown(self):
+        with self.assertRaises(ImproperlyConfigured):
+            check_callback_configuration()

formidable/__init__.py

@@ -0,0 +1 @@
+default_app_config = 'formidable.app.FormidableConfig'

formidable/app.py

@@ -0,0 +1,23 @@
+"""
+Django-formidable app definition.
+
+The :class:`FormidableConfig` checks various configuration settings:
+
+* post-update and post-create callbacks
+"""
+
+from django.apps import AppConfig
+
+
+class FormidableConfig(AppConfig):
+    """
+    Formidable application configuration class. Runs various checks.
+    """
+    name = 'formidable'
+
+    def ready(self):
+        """
+        Run various checks when ready
+        """
+        from .views import check_callback_configuration
+        check_callback_configuration()

formidable/views.py

@@ -4,6 +4,7 @@
 import logging
 
 from django.conf import settings
+from django.core.exceptions import ImproperlyConfigured
 from django.db.models import Prefetch
 
 import six
@@ -31,17 +32,39 @@
 def extract_function(func_name):
     """
     Return a function out of a namespace
+
+    Return None if the function is not loadable
     """
     func = None
     try:
         func = import_from_string(func_name, '')
-    except ImportError:
+    except (ImportError, ValueError):
         logger.error(
             "An error has occurred impossible to import %s", func_name
         )
     return func
 
 
+def check_callback_configuration():
+    settings_names = (
+        'FORMIDABLE_POST_UPDATE_CALLBACK_SUCCESS',
+        'FORMIDABLE_POST_UPDATE_CALLBACK_FAIL',
+        'FORMIDABLE_POST_CREATE_CALLBACK_SUCCESS',
+        'FORMIDABLE_POST_CREATE_CALLBACK_FAIL',
+    )
+    settings_values = map(
+        lambda k: (k, getattr(settings, k, None)),
+        settings_names)
+    settings_values = filter(lambda item: item[1], settings_values)
+    for key, value in settings_values:
+        func = extract_function(value)
+        if not func:
+            raise ImproperlyConfigured(
+                "Settings {} points to a non-existant function: `{}`".format(
+                    key, value))
+    return True
+
+
 class CallbackMixin(object):
     success_callback_settings = ''
     failure_callback_settings = ''