Raise error when setting a removed rest_framework setting for #3644

rest_framework/settings.py

@@ -19,6 +19,8 @@
 """
 from __future__ import unicode_literals
 
+import warnings
+
 from django.conf import settings
 from django.test.signals import setting_changed
 from django.utils import six
@@ -135,6 +137,12 @@
 )
 
 
+# List of settings that have been removed
+REMOVED_SETTINGS = (
+    "PAGINATE_BY", "PAGINATE_BY_PARAM", "MAX_PAGINATE_BY",
+)
+
+
 def perform_import(val, setting_name):
     """
     If the given setting is a string import notation,
@@ -177,7 +185,7 @@ class APISettings(object):
     """
     def __init__(self, user_settings=None, defaults=None, import_strings=None):
         if user_settings:
-            self._user_settings = user_settings
+            self._user_settings = self.__check_user_settings(user_settings)
         self.defaults = defaults or DEFAULTS
         self.import_strings = import_strings or IMPORT_STRINGS
 
@@ -206,6 +214,13 @@ def __getattr__(self, attr):
         setattr(self, attr, val)
         return val
 
+    def __check_user_settings(self, user_settings):
+        SETTINGS_DOC = "http://www.django-rest-framework.org/api-guide/settings/"
+        for setting in REMOVED_SETTINGS:
+            if setting in user_settings:
+                warnings.warn("The '%s' setting has been removed. Please refer to '%s' for available settings." % (setting, SETTINGS_DOC), DeprecationWarning)
+        return user_settings
+
 
 api_settings = APISettings(None, DEFAULTS, IMPORT_STRINGS)
 

tests/test_settings.py

@@ -1,5 +1,7 @@
 from __future__ import unicode_literals
 
+import warnings
+
 from django.test import TestCase
 
 from rest_framework.settings import APISettings
@@ -18,6 +20,19 @@ def test_import_error_message_maintained(self):
         with self.assertRaises(ImportError):
             settings.DEFAULT_RENDERER_CLASSES
 
+    def test_warning_raised_on_removed_setting(self):
+        """
+        Make sure user is alerted with an error when a removed setting
+        is set.
+        """
+        with warnings.catch_warnings(record=True) as w:
+            warnings.simplefilter("always")
+            APISettings({
+                'MAX_PAGINATE_BY': 100
+            })
+            self.assertEqual(len(w), 1)
+            self.assertTrue(issubclass(w[-1].category, DeprecationWarning))
+
 
 class TestSettingTypes(TestCase):
     def test_settings_consistently_coerced_to_list(self):