Set self.kwargs in Binding.trigger_inbound when setting self.message (#541)

Allows options passed in (like a consumer) to be accessible to further code.

channels/binding/base.py

@@ -214,6 +214,7 @@ class Binding(object):
         from django.contrib.auth.models import AnonymousUser
         self = cls()
         self.message = message
+        self.kwargs = kwargs
         # Deserialize message
         self.action, self.pk, self.data = self.deserialize(self.message)
         self.user = getattr(self.message, "user", AnonymousUser())

tests/test_binding.py

@@ -349,3 +349,29 @@ class TestsBinding(ChannelTestCase):
 
         self.assertIsNone(User.objects.filter(pk=user.pk).first())
         self.assertIsNone(client.receive())
+
+    def test_route_params_saved_in_kwargs(self):
+
+        class UserBinding(WebsocketBinding):
+            model = User
+            stream = 'users'
+            fields = ['username', 'email', 'password', 'last_name']
+
+            @classmethod
+            def group_names(cls, instance):
+                return ['users_outbound']
+
+            def has_permission(self, user, action, pk):
+                return True
+
+        class Demultiplexer(WebsocketDemultiplexer):
+            consumers = {
+                'users': UserBinding.consumer,
+            }
+
+            groups = ['inbound']
+
+        with apply_routes([Demultiplexer.as_route(path='/path/(?P<id>\d+)')]):
+            client = HttpClient()
+            consumer = client.send_and_consume('websocket.connect', path='/path/789')
+            self.assertEqual(consumer.kwargs['id'], '789')