From b1b58762a3d84ac4cdc6553e8ed06983fd3502ca Mon Sep 17 00:00:00 2001
From: Dustin Farris <dustin@dustinfarris.com>
Date: Mon, 13 Jan 2014 11:47:44 -0500
Subject: [PATCH] Move models.resolve_model to serializers._resolve_model

---
 rest_framework/models.py                      | 23 +--------------
 rest_framework/serializers.py                 | 29 +++++++++++++++++--
 .../{test_models.py => test_serializers.py}   | 14 ++++-----
 3 files changed, 35 insertions(+), 31 deletions(-)
 rename rest_framework/tests/{test_models.py => test_serializers.py} (62%)

diff --git a/rest_framework/models.py b/rest_framework/models.py
index 249cdd828..5b53a5264 100644
--- a/rest_framework/models.py
+++ b/rest_framework/models.py
@@ -1,22 +1 @@
-import inspect
-
-from django.db import models
-
-
-def resolve_model(obj):
-    """
-    Resolve supplied `obj` to a Django model class.
-
-    `obj` must be a Django model class, or a string representation
-    of one.
-
-    String representations should have the format:
-        'appname.ModelName'
-    """
-    if type(obj) == str and len(obj.split('.')) == 2:
-        app_name, model_name = obj.split('.')
-        return models.get_model(app_name, model_name)
-    elif inspect.isclass(obj) and issubclass(obj, models.Model):
-        return obj
-    else:
-        raise ValueError("{0} is not a valid Django model".format(obj))
+# Just to keep things like ./manage.py test happy
diff --git a/rest_framework/serializers.py b/rest_framework/serializers.py
index 6b31c3043..0ea2cadbf 100644
--- a/rest_framework/serializers.py
+++ b/rest_framework/serializers.py
@@ -13,14 +13,15 @@ response content is handled by parsers and renderers.
 from __future__ import unicode_literals
 import copy
 import datetime
+import inspect
 import types
 from decimal import Decimal
+from django.core.exceptions import ImproperlyConfigured
 from django.core.paginator import Page
 from django.db import models
 from django.forms import widgets
 from django.utils.datastructures import SortedDict
 from rest_framework.compat import get_concrete_model, six
-from rest_framework.models import resolve_model
 
 # Note: We do the following so that users of the framework can use this style:
 #
@@ -33,6 +34,27 @@ from rest_framework.relations import *
 from rest_framework.fields import *
 
 
+def _resolve_model(obj):
+    """
+    Resolve supplied `obj` to a Django model class.
+
+    `obj` must be a Django model class itself, or a string
+    representation of one.  Useful in situtations like GH #1225 where
+    Django may not have resolved a string-based reference to a model in
+    another model's foreign key definition.
+
+    String representations should have the format:
+        'appname.ModelName'
+    """
+    if type(obj) == str and len(obj.split('.')) == 2:
+        app_name, model_name = obj.split('.')
+        return models.get_model(app_name, model_name)
+    elif inspect.isclass(obj) and issubclass(obj, models.Model):
+        return obj
+    else:
+        raise ValueError("{0} is not a Django model".format(obj))
+
+
 def pretty_name(name):
     """Converts 'first_name' to 'First name'"""
     if not name:
@@ -657,7 +679,10 @@ class ModelSerializer(Serializer):
             if model_field.rel:
                 to_many = isinstance(model_field,
                                      models.fields.related.ManyToManyField)
-                related_model = resolve_model(model_field.rel.to)
+                try:
+                    related_model = _resolve_model(model_field.rel.to)
+                except ValueError as error_message:
+                    raise ImproperlyConfigured(error_message)
 
                 if to_many and not model_field.rel.through._meta.auto_created:
                     has_through_model = True
diff --git a/rest_framework/tests/test_models.py b/rest_framework/tests/test_serializers.py
similarity index 62%
rename from rest_framework/tests/test_models.py
rename to rest_framework/tests/test_serializers.py
index 5e92d48ae..082a400ca 100644
--- a/rest_framework/tests/test_models.py
+++ b/rest_framework/tests/test_serializers.py
@@ -1,28 +1,28 @@
 from django.db import models
 from django.test import TestCase
 
-from rest_framework.models import resolve_model
+from rest_framework.serializers import _resolve_model
 from rest_framework.tests.models import BasicModel
 
 
 class ResolveModelTests(TestCase):
     """
-    `resolve_model` should return a Django model class given the
+    `_resolve_model` should return a Django model class given the
     provided argument is a Django model class itself, or a properly
     formatted string representation of one.
     """
     def test_resolve_django_model(self):
-        resolved_model = resolve_model(BasicModel)
+        resolved_model = _resolve_model(BasicModel)
         self.assertEqual(resolved_model, BasicModel)
 
     def test_resolve_string_representation(self):
-        resolved_model = resolve_model('tests.BasicModel')
+        resolved_model = _resolve_model('tests.BasicModel')
         self.assertEqual(resolved_model, BasicModel)
 
     def test_resolve_non_django_model(self):
         with self.assertRaises(ValueError):
-            resolve_model(TestCase)
+            _resolve_model(TestCase)
 
-    def test_resolve_with_improper_string_representation(self):
+    def test_resolve_improper_string_representation(self):
         with self.assertRaises(ValueError):
-            resolve_model('BasicModel')
+            _resolve_model('BasicModel')