custom none name

CONTRIBUTING.rst

@@ -30,6 +30,7 @@ demo testing
 to ensure the app behaves as expected, run the following::
 
   $ cd test_app
+  $ python manage.py migrate
   $ python manage.py runserver
 
 then, visit ``http://localhost:8000/`` in your browser and confirm it produces a valid CSV.

djqscsv/djqscsv.py

@@ -14,7 +14,7 @@
 # the rest will be passed along to the csv writer
 DJQSCSV_KWARGS = {
     'field_header_map', 'field_serializer_map', 'use_verbose_names',
-    'field_order'}
+    'field_order', 'custom_none_name'}
 
 
 class CSVException(Exception):
@@ -78,6 +78,7 @@ def _iter_csv(queryset, file_obj, **kwargs):
     field_header_map = kwargs.get('field_header_map', {})
     field_serializer_map = kwargs.get('field_serializer_map', {})
     use_verbose_names = kwargs.get('use_verbose_names', True)
+    custom_none_name = kwargs.get('custom_none_name', None)
     field_order = kwargs.get('field_order', None)
 
     csv_kwargs = {'encoding': 'utf-8'}
@@ -152,7 +153,8 @@ def _iter_csv(queryset, file_obj, **kwargs):
     yield writer.writerow(merged_header_map)
 
     for record in values_qs:
-        record = _sanitize_record(field_serializer_map, record)
+        record = _sanitize_record(field_serializer_map, record,
+                                  custom_none_name)
         yield writer.writerow(record)
 
 
@@ -186,7 +188,7 @@ def _validate_and_clean_filename(filename):
     return filename
 
 
-def _sanitize_record(field_serializer_map, record):
+def _sanitize_record(field_serializer_map, record, custom_none_name):
 
     def _serialize_value(value):
         # provide default serializer for the case when
@@ -201,11 +203,16 @@ def _serialize_value(value):
         if val is not None:
             serializer = field_serializer_map.get(key, _serialize_value)
             newval = serializer(val)
+            # If the user provided None
+            if newval is None:
+                newval = custom_none_name
             # If the user provided serializer did not produce a string,
             # coerce it to a string
             if not isinstance(newval, six.text_type):
                 newval = six.text_type(newval)
             obj[key] = newval
+        elif custom_none_name:
+            obj[key] = custom_none_name
 
     return obj
 

test_app/djqscsv_tests/tests/test_utilities.py

@@ -47,19 +47,41 @@ class SanitizeUnicodeRecordTests(TestCase):
     def test_sanitize(self):
         record = {'name': 'Tenar',
                   'nickname': u'\ufeffThe White Lady of Gont'}
-        sanitized = djqscsv._sanitize_record({}, record)
+        sanitized = djqscsv._sanitize_record({}, record, None)
         self.assertEqual(sanitized,
                          {'name': 'Tenar',
                           'nickname': u'\ufeffThe White Lady of Gont'})
 
     def test_sanitize_date(self):
         record = {'name': 'Tenar',
                   'created': datetime.datetime(1, 1, 1)}
-        sanitized = djqscsv._sanitize_record({}, record)
+        sanitized = djqscsv._sanitize_record({}, record, None)
         self.assertEqual(sanitized,
                          {'name': 'Tenar',
                           'created': '0001-01-01T00:00:00'})
 
+    def test_sanitize_with_custom_none_name(self):
+        """
+        Ensure we retrieve custom none name
+        """
+        record = {'name': 'Tenar',
+                  'created': None}
+        custom_name_for_nones = "custom_name_for_nones"
+        sanitized = djqscsv._sanitize_record({}, record,
+                                             custom_name_for_nones)
+        self.assertEqual(sanitized,
+                         {'name': 'Tenar',
+                          'created': custom_name_for_nones})
+
+        record = {'name': 'Tenar',
+                  'created': datetime.datetime(1, 1, 1)}
+        serializer = {'created': lambda x: None}
+        sanitized = djqscsv._sanitize_record(serializer, record,
+                                             custom_name_for_nones)
+        self.assertEqual(sanitized,
+                         {'name': 'Tenar',
+                          'created': custom_name_for_nones})
+
     def test_sanitize_date_with_non_string_formatter(self):
         """
         This test is only to make sure an edge case provides a sane
@@ -68,14 +90,14 @@ def test_sanitize_date_with_non_string_formatter(self):
         """
         record = {'name': 'Tenar'}
         serializer = {'name': lambda d: len(d)}
-        sanitized = djqscsv._sanitize_record(serializer, record)
+        sanitized = djqscsv._sanitize_record(serializer, record, None)
         self.assertEqual(sanitized, {'name': '5'})
 
     def test_sanitize_date_with_formatter(self):
         record = {'name': 'Tenar',
                   'created': datetime.datetime(1973, 5, 13)}
         serializer = {'created': lambda d: d.strftime('%Y-%m-%d')}
-        sanitized = djqscsv._sanitize_record(serializer, record)
+        sanitized = djqscsv._sanitize_record(serializer, record, None)
         self.assertEqual(sanitized,
                          {'name': 'Tenar',
                           'created': '1973-05-13'})
@@ -84,7 +106,7 @@ def test_sanitize_date_with_bad_formatter(self):
         record = {'name': 'Tenar',
                   'created': datetime.datetime(1973, 5, 13)}
         with self.assertRaises(AttributeError):
-            djqscsv._sanitize_record(attrgetter('day'), record)
+            djqscsv._sanitize_record(attrgetter('day'), record, None)
 
 
 class AppendDatestampTests(TestCase):