Move models.resolve_model to serializers._resolve_model

1 files changed, 27 insertions, 2 deletions

diff --git a/rest_framework/serializers.py b/rest_framework/serializers.py
index 6b31c304..0ea2cadb 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