Use new value_from_object in preference to internal _get_val_from_obj

rest_framework/compat.py

@@ -122,6 +122,12 @@ def get_related_model(field):
     return field.remote_field.model
 
 
+def value_from_object(field, obj):
+    if django.VERSION < (1, 9):
+        return field._get_val_from_obj(obj)
+    field.value_from_object(obj)
+
+
 # contrib.postgres only supported from 1.8 onwards.
 try:
     from django.contrib.postgres import fields as postgres_fields

rest_framework/fields.py

@@ -31,7 +31,7 @@
 
 from rest_framework import ISO_8601
 from rest_framework.compat import (
-    get_remote_field, unicode_repr, unicode_to_repr
+    get_remote_field, unicode_repr, unicode_to_repr, value_from_object
 )
 from rest_framework.exceptions import ValidationError
 from rest_framework.settings import api_settings
@@ -1687,7 +1687,7 @@ def get_attribute(self, obj):
         return obj
 
     def to_representation(self, obj):
-        value = self.model_field._get_val_from_obj(obj)
+        value = value_from_object(self.model_field, obj)
         if is_protected_type(value):
             return value
         return self.model_field.value_to_string(obj)