diff -r 66243fb5e3fc -r 2ff785d7026c server/python/django2/renkanmanager/tests/v1_0/tests_renkan.py
--- a/server/python/django2/renkanmanager/tests/v1_0/tests_renkan.py	Tue Mar 01 17:39:39 2016 +0100
+++ b/server/python/django2/renkanmanager/tests/v1_0/tests_renkan.py	Thu Mar 03 17:09:27 2016 +0100
@@ -13,10 +13,10 @@
     
     def setUp(self):
         User.objects.create_superuser("blop", "blop@blop.com", "blop")
-        self.user = User.objects.get(username="blop")
+        self.user = User.objects.get_by_natural_key(username="blop")
         _ = self.client.login(username="blop", password="blop")
         User.objects.create_user("blip", "blip@blip.com", "blip")
-        self.unauthorized_user = User.objects.get(username="blip")
+        self.unauthorized_user = User.objects.get_by_natural_key(username="blip")
         
         # POSTing test workspace
         post_url = reverse("v1.0:workspace_list")
@@ -83,9 +83,9 @@
         new_renkan_guid = post_response_dict.get("id", "")
         new_renkan = Renkan.objects.get(renkan_guid=new_renkan_guid)
         # GUIDs and username
-        self.assertEqual(self.user.username, post_response_dict.get("created_by", ""))
-        self.assertEqual(self.user.username, post_response_dict.get("last_updated_by", ""))
-        self.assertEqual(self.user.username, new_renkan.creator.username)
+        self.assertEqual(getattr(self.user, User.USERNAME_FIELD), post_response_dict.get("created_by", ""))
+        self.assertEqual(getattr(self.user, User.USERNAME_FIELD), post_response_dict.get("last_updated_by", ""))
+        self.assertEqual(getattr(self.user, User.USERNAME_FIELD), getattr(new_renkan.creator, User.USERNAME_FIELD))
         # Content and title extracted from revision
         self.assertEqual(new_renkan.title, self.first_test_title)
         self.assertEqual(new_renkan.content, self.first_test_content)
@@ -97,8 +97,8 @@
         new_renkan_revision_guid = post_response_dict.get("current_revision_id", "")
         new_renkan_revision = Revision.objects.get(revision_guid = new_renkan_revision_guid)
         # GUIDs and username
-        self.assertEqual(self.user.username, new_renkan_revision.creator.username)
-        self.assertEqual(self.user.username, new_renkan_revision.last_updated_by.username)
+        self.assertEqual(getattr(self.user, User.USERNAME_FIELD), getattr(new_renkan_revision.creator, User.USERNAME_FIELD))
+        self.assertEqual(getattr(self.user, User.USERNAME_FIELD), getattr(new_renkan_revision.last_updated_by, User.USERNAME_FIELD))
         # Title and content
         #    in the response
         self.assertEqual(post_response_dict.get("title", ""), self.first_test_title)
@@ -129,9 +129,9 @@
         # GUIDs and username
         self.assertEqual(self.test_workspace_guid, post_response_dict.get("workspace_id", ""))
         self.assertEqual(self.test_workspace_guid, new_renkan.workspace_guid)
-        self.assertEqual(self.user.username, post_response_dict.get("created_by", ""))
-        self.assertEqual(self.user.username, post_response_dict.get("last_updated_by", ""))
-        self.assertEqual(self.user.username, new_renkan.creator.username)
+        self.assertEqual(getattr(self.user, User.USERNAME_FIELD), post_response_dict.get("created_by", ""))
+        self.assertEqual(getattr(self.user, User.USERNAME_FIELD), post_response_dict.get("last_updated_by", ""))
+        self.assertEqual(getattr(self.user, User.USERNAME_FIELD), getattr(new_renkan.creator, User.USERNAME_FIELD))
         # Content and title extracted from revision
         self.assertEqual(new_renkan.title, self.second_test_title)
         self.assertEqual(new_renkan.content, self.second_test_content)
@@ -195,8 +195,8 @@
         get_response_dict = json.loads(get_response.content.decode())
         self.assertEqual(new_renkan_guid, get_response_dict.get("id", ""))
         self.assertEqual(new_revision_guid, get_response_dict.get("current_revision_id", ""))
-        self.assertEqual(self.user.username, get_response_dict.get("created_by", ""))
-        self.assertEqual(self.user.username, get_response_dict.get("last_updated_by", ""))
+        self.assertEqual(getattr(self.user, User.USERNAME_FIELD), get_response_dict.get("created_by", ""))
+        self.assertEqual(getattr(self.user, User.USERNAME_FIELD), get_response_dict.get("last_updated_by", ""))
         
         ###################################################
         # GETting with wrong guid
@@ -406,8 +406,8 @@
         self.assertEqual(first_copy_response_dict.get("source_revision_id"), source_revision_guid)
         self.assertEqual(first_copy_response_dict.get("title", ""), "new_title_copy_1")
         self.assertEqual(first_copy_response_dict.get("content", ""), self.first_test_content)
-        self.assertEqual(first_copy_response_dict.get("created_by", ""), self.user.username)
-        self.assertEqual(first_copy_response_dict.get("last_updated_by", ""), self.user.username)
+        self.assertEqual(first_copy_response_dict.get("created_by", ""), getattr(self.user, User.USERNAME_FIELD))
+        self.assertEqual(first_copy_response_dict.get("last_updated_by", ""), getattr(self.user, User.USERNAME_FIELD))
         #     in the database
         first_copy = Renkan.objects.get(renkan_guid=first_copy_response_dict.get("id", ""))
         first_copy_revision = Revision.objects.get(revision_guid=first_copy_response_dict.get("current_revision_id", ""))
@@ -415,9 +415,9 @@
         self.assertEqual(first_copy.content, self.first_test_content)
         self.assertEqual(first_copy_revision.title, "new_title_copy_1")
         self.assertEqual(first_copy_revision.content, self.first_test_content)
-        self.assertEqual(first_copy.creator.username, self.user.username)
-        self.assertEqual(first_copy_revision.creator.username, self.user.username)
-        self.assertEqual(first_copy_revision.last_updated_by.username, self.user.username)
+        self.assertEqual(getattr(first_copy.creator, User.USERNAME_FIELD), getattr(self.user, User.USERNAME_FIELD))
+        self.assertEqual(getattr(first_copy_revision.creator, User.USERNAME_FIELD), getattr(self.user, User.USERNAME_FIELD))
+        self.assertEqual(getattr(first_copy_revision.last_updated_by, User.USERNAME_FIELD), getattr(self.user, User.USERNAME_FIELD))
         
         ###################################################
         # POSTing copy with source_renkan_guid in data
@@ -435,8 +435,8 @@
         self.assertEqual(second_copy_response_dict.get("source_revision_id"), source_revision_guid)
         self.assertEqual(second_copy_response_dict.get("title", ""), "new_title_copy_2")
         self.assertEqual(second_copy_response_dict.get("content", ""), self.first_test_content)
-        self.assertEqual(second_copy_response_dict.get("created_by", ""), self.user.username)
-        self.assertEqual(second_copy_response_dict.get("last_updated_by", ""), self.user.username)
+        self.assertEqual(second_copy_response_dict.get("created_by", ""), getattr(self.user, User.USERNAME_FIELD))
+        self.assertEqual(second_copy_response_dict.get("last_updated_by", ""), getattr(self.user, User.USERNAME_FIELD))
         #     in the database
         second_copy = Renkan.objects.get(renkan_guid=second_copy_response_dict.get("id", ""))
         second_copy_revision = Revision.objects.get(revision_guid=second_copy_response_dict.get("current_revision_id", ""))
@@ -444,9 +444,9 @@
         self.assertEqual(second_copy.content, self.first_test_content)
         self.assertEqual(second_copy_revision.title, "new_title_copy_2")
         self.assertEqual(second_copy_revision.content, self.first_test_content)
-        self.assertEqual(second_copy.creator.username, self.user.username)
-        self.assertEqual(second_copy_revision.creator.username, self.user.username)
-        self.assertEqual(second_copy_revision.last_updated_by.username, self.user.username)
+        self.assertEqual(getattr(second_copy.creator, User.USERNAME_FIELD), getattr(self.user, User.USERNAME_FIELD))
+        self.assertEqual(getattr(second_copy_revision.creator, User.USERNAME_FIELD), getattr(self.user, User.USERNAME_FIELD))
+        self.assertEqual(getattr(second_copy_revision.last_updated_by, User.USERNAME_FIELD), getattr(self.user, User.USERNAME_FIELD))
         
         ###################################################
         # POSTing copy with query arg for REVISION guid
@@ -464,8 +464,8 @@
         self.assertEqual(third_copy_response_dict.get("source_revision_id"), source_revision_guid)
         self.assertEqual(third_copy_response_dict.get("title", ""), "new_title_copy_3")
         self.assertEqual(third_copy_response_dict.get("content", ""), self.first_test_content)
-        self.assertEqual(third_copy_response_dict.get("created_by", ""), self.user.username)
-        self.assertEqual(third_copy_response_dict.get("last_updated_by", ""), self.user.username)
+        self.assertEqual(third_copy_response_dict.get("created_by", ""), getattr(self.user, User.USERNAME_FIELD))
+        self.assertEqual(third_copy_response_dict.get("last_updated_by", ""), getattr(self.user, User.USERNAME_FIELD))
         #     in the database
         third_copy = Renkan.objects.get(renkan_guid=third_copy_response_dict.get("id", ""))
         third_copy_revision = Revision.objects.get(revision_guid=third_copy_response_dict.get("current_revision_id", ""))
@@ -473,9 +473,9 @@
         self.assertEqual(third_copy.content, self.first_test_content)
         self.assertEqual(third_copy_revision.title, "new_title_copy_3")
         self.assertEqual(third_copy_revision.content, self.first_test_content)
-        self.assertEqual(third_copy.creator.username, self.user.username)
-        self.assertEqual(third_copy_revision.creator.username, self.user.username)
-        self.assertEqual(third_copy_revision.last_updated_by.username, self.user.username)
+        self.assertEqual(getattr(third_copy.creator, User.USERNAME_FIELD), getattr(self.user, User.USERNAME_FIELD))
+        self.assertEqual(getattr(third_copy_revision.creator, User.USERNAME_FIELD), getattr(self.user, User.USERNAME_FIELD))
+        self.assertEqual(getattr(third_copy_revision.last_updated_by, User.USERNAME_FIELD), getattr(self.user, User.USERNAME_FIELD))
         
         ###################################################
         # POSTing copy with source_revision_guid in data
@@ -493,8 +493,8 @@
         self.assertEqual(fourth_copy_response_dict.get("source_revision_id"), source_revision_guid)
         self.assertEqual(fourth_copy_response_dict.get("title", ""), self.first_test_title)
         self.assertEqual(fourth_copy_response_dict.get("content", ""), self.first_test_content)
-        self.assertEqual(fourth_copy_response_dict.get("created_by", ""), self.user.username)
-        self.assertEqual(fourth_copy_response_dict.get("last_updated_by", ""), self.user.username)
+        self.assertEqual(fourth_copy_response_dict.get("created_by", ""), getattr(self.user, User.USERNAME_FIELD))
+        self.assertEqual(fourth_copy_response_dict.get("last_updated_by", ""), getattr(self.user, User.USERNAME_FIELD))
         #     in the database
         fourth_copy = Renkan.objects.get(renkan_guid=fourth_copy_response_dict.get("id", ""))
         fourth_copy_revision = Revision.objects.get(revision_guid=fourth_copy_response_dict.get("current_revision_id", ""))
@@ -502,9 +502,9 @@
         self.assertEqual(fourth_copy.content, self.first_test_content)
         self.assertEqual(fourth_copy_revision.title, self.first_test_title)
         self.assertEqual(fourth_copy_revision.content, self.first_test_content)
-        self.assertEqual(fourth_copy.creator.username, self.user.username)
-        self.assertEqual(fourth_copy_revision.creator.username, self.user.username)
-        self.assertEqual(fourth_copy_revision.last_updated_by.username, self.user.username)
+        self.assertEqual(getattr(fourth_copy.creator, User.USERNAME_FIELD), getattr(self.user, User.USERNAME_FIELD))
+        self.assertEqual(getattr(fourth_copy_revision.creator, User.USERNAME_FIELD), getattr(self.user, User.USERNAME_FIELD))
+        self.assertEqual(getattr(fourth_copy_revision.last_updated_by, User.USERNAME_FIELD), getattr(self.user, User.USERNAME_FIELD))
         
         
         ###################################################