Merge pull request #321 from ericdwang/master

Fix AttributeErrors when importing readonly fields from annotated values

AUTHORS

@@ -49,3 +49,4 @@ The following is a list of much appreciated contributors:
 * AyumuKasuga (Andrey Kostakov)
 * luto
 * gallochri (Christian Galeffi)
+* ericdwang (Eric Wang)

import_export/fields.py

@@ -73,7 +73,7 @@ def get_value(self, obj):
 
         for attr in attrs:
             try:
-                value = getattr(value, attr)
+                value = getattr(value, attr, None)
             except (ValueError, ObjectDoesNotExist):
                 # needs to have a primary key value before a many-to-many
                 # relationship can be used.

tests/core/tests/resources_tests.py

@@ -5,6 +5,7 @@
 from copy import deepcopy
 
 from django.db import models
+from django.db.models import Count
 from django.db.models.fields import FieldDoesNotExist
 from django.test import (
         TestCase,
@@ -514,6 +515,32 @@ def field_from_django_field(self, field_name, django_field, readonly):
         resource = B()
         self.assertEqual({'sound': 'quack'}, B.fields['published'])
 
+    def test_readonly_annotated_field_import_and_export(self):
+        class B(BookResource):
+            total_categories = fields.Field('total_categories', readonly=True)
+
+            class Meta:
+                model = Book
+                skip_unchanged = True
+
+        cat1 = Category.objects.create(name='Cat 1')
+        self.book.categories.add(cat1)
+
+        resource = B()
+
+        # Verify that the annotated field is correctly exported
+        dataset = resource.export(
+            Book.objects.annotate(total_categories=Count('categories')))
+        self.assertEqual(int(dataset.dict[0]['total_categories']), 1)
+
+        # Verify that importing the annotated field raises no errors and that
+        # the rows are skipped
+        result = resource.import_data(dataset, raise_errors=True)
+        self.assertFalse(result.has_errors())
+        self.assertEqual(len(result.rows), len(dataset))
+        self.assertEqual(
+            result.rows[0].import_type, results.RowResult.IMPORT_TYPE_SKIP)
+
 
 class ModelResourceTransactionTest(TransactionTestCase):