Send the config parameter as sender for the signal

constance/backends/database/__init__.py

@@ -4,7 +4,7 @@ from django.core.exceptions import ImproperlyConfigured
 from django.db.models.signals import post_save
 
 from .. import Backend
-from ... import settings, signals
+from ... import settings, signals, config
 
 
 class DatabaseBackend(Backend):
@@ -86,12 +86,13 @@ class DatabaseBackend(Backend):
         if self._cache:
             self._cache.set(key, value)
 
-        signals.config_updated.send(sender='constance', key=key, value=value)
+        signals.config_updated.send(
+            sender=config, updated_key=key, new_value=value
+        )
 
     def clear(self, sender, instance, created, **kwargs):
         if self._cache and not created:
-            keys = [self.add_prefix(k)
-                    for k in settings.CONFIG.keys()]
+            keys = [self.add_prefix(k) for k in settings.CONFIG.keys()]
             keys.append(self.add_prefix(self._autofill_cachekey))
             self._cache.delete_many(keys)
             self.autofill()

constance/backends/redisd.py

@@ -3,7 +3,7 @@ from django.utils import six
 from django.utils.six.moves import zip
 
 from . import Backend
-from .. import settings, utils, signals
+from .. import settings, utils, signals, config
 
 try:
     from cPickle import loads, dumps
@@ -49,4 +49,6 @@ class RedisBackend(Backend):
 
     def set(self, key, value):
         self._rd.set(self.add_prefix(key), dumps(value))
-        signals.config_updated.send(sender='constance', key=key, value=value)
+        signals.config_updated.send(
+            sender=config, updated_key=key, new_value=value
+        )

docs/index.rst

@@ -81,11 +81,15 @@ You can use it as:
     from constance.signals import config_updated
 
     @receiver(config_updated)
-    def constance_updated(sender, key, value, **kwargs):
-        print(sender, key, value)
+    def constance_updated(sender, updated_key, new_value, **kwargs):
+        print(sender, updated_key, new_value)
 
-In case you need it the sender is `constance`, and the key and value are
-the ones just changed.
+The sender is the `config` object, and the `updated_key` and `new_value`
+are the ones just changed.
+
+This callback will get the `config` object as the first parameter so you
+can have an isolated function where you can access the `config` object
+without dealing with additional imports.
 
 
 Custom fields