some refactoring and adds tests for title in self link

chain/core/api.py

@@ -112,7 +112,7 @@ def __init__(self, child_resource_class, reverse_name, embed=False):
 
     def create_parent_filter(self, parent):
         return {self._reverse_name + '_id': parent._obj.id}
-    
+
     def serialize(self, parent, request, cache):
         queryset = self._child_resource_class.queryset
 
@@ -204,7 +204,7 @@ def __init__(self, obj=None, is_list=None, data=None, request=None,
         self._request = request
         self._limit = limit or self.page_size
         self._offset = offset or 0
-    
+
     @classmethod
     def get_object_by_id(cls, id):
         return cls.queryset.get(id=id)
@@ -221,15 +221,7 @@ def serialize_single(self, embed=True, cache=None, rels=True, *args, **kwargs):
         if not embed:
             # this is just a link, don't embed the full object
             data['href'] = self.get_single_href()
-            title = self.display_field
-            if title in self.model_fields:
-                data['title'] = self.serialize_field(getattr(self._obj, title))
-            elif title in self.stub_fields.keys():
-                stub_data = getattr(self._obj, title)
-                data['title'] = getattr(stub_data, self.stub_fields[title])
-            else:
-                raise NotImplementedError(
-                    'display_field must be a model field or stub field')
+            data['title'] = self.get_title()
             return data
         if rels:
             data['_links'] = {
@@ -253,14 +245,7 @@ def serialize_single(self, embed=True, cache=None, rels=True, *args, **kwargs):
                 data['_links'][field_name] = collection.serialize(
                     self, self._request, cache)
 
-            title = self.display_field
-            if title in self.model_fields:
-                data['_links']['self']['title'] = self.serialize_field(
-                    getattr(self._obj, title))
-            elif title in self.stub_fields.keys():
-                stub_data = getattr(self._obj, title)
-                data['_links']['self']['title'] = getattr(stub_data,
-                    self.stub_fields[title])
+            data['_links']['self']['title'] = self.get_title()
 
         for field_name in self.model_fields:
             data[field_name] = self.serialize_field(
@@ -305,6 +290,18 @@ def get_total_count(self):
         self._total_count = qs.count()
         return self._total_count
 
+    def get_title(self):
+        tfield = self.display_field
+        if tfield in self.model_fields:
+            return self.serialize_field(getattr(self._obj, tfield))
+        elif tfield in self.stub_fields.keys():
+            stub_data = getattr(self._obj, tfield)
+            return getattr(stub_data, self.stub_fields[tfield])
+        else:
+            raise NotImplementedError(
+                'display_field must be a model field or stub field')
+
+
     def get_queryset(self):
         '''Returns the queryset resulting from this request, including
         all filtering, and pagination'''

chain/core/tests.py

@@ -549,6 +549,7 @@ def test_sites_should_be_postable(self):
         db_obj = Site.objects.get(name='MIT Media Lab')
         self.assertEqual(new_site['name'], response.name)
         self.assertEqual(new_site['name'], db_obj.name)
+        self.assertEqual(new_site['name'], response.links['self'].title)
         self.assertEqual(new_site['rawZMQStream'],
                          response.links.rawZMQStream.href)
         self.assertEqual(new_site['rawZMQStream'],
@@ -724,7 +725,8 @@ def test_device_should_be_postable_to_a_site(self):
             "name": "Unit Test Thermostat 42",
             "room": "E14-548R"
         }
-        self.create_resource(dev_url, new_device)
+        response = self.create_resource(dev_url, new_device)
+        self.assertEqual(new_device['name'], response.links['self'].title)
         # make sure that a device now exists with the right name
         db_device = Device.objects.get(name=new_device['name'])
         # make sure that the device is set up in the right site
@@ -829,10 +831,11 @@ def test_sensors_should_be_postable_to_newly_posted_device(self):
             'metric': 'Beauty',
             'unit': 'millihelen',
         }
-        self.create_resource(sensors.links['createForm'].href, new_sensor)
+        response = self.create_resource(sensors.links['createForm'].href, new_sensor)
         db_sensor = ScalarSensor.objects.get(metric__name='Beauty',
                                              device__name=device.name)
         self.assertEqual('millihelen', db_sensor.unit.name)
+        self.assertEqual('Beauty', response.links['self'].title)
 
     def test_sensor_should_have_data_url(self):
         sensor = self.get_a_sensor()
@@ -886,6 +889,7 @@ def test_presence_sensors_should_be_postable_to_existing_device(self):
         db_sensor = PresenceSensor.objects.get(metric__name='rfid',
                                                device__name=device.name)
         self.assertTrue(db_sensor is not None)
+        self.assertEqual(new_sensor_res.links['self'].title, new_sensor['metric'])
 
         # Reload the list of sensors:
         sensors = self.get_resource(device.links['ch:sensors'].href)