def get_diff_data(serializer):
if not has_changes(serializer):
return None
data = {}
changed_fields = get_changed_fields(serializer)
orig = get_original_representation(serializer)
for column_name in serializer.initial_data:
field = serializer.fields.get(column_name, None)
if not field:
continue
data[column_name] = field_data = []
if column_name in orig:
field_data.append(
fields.to_string_representation(field, orig[column_name])
)
else:
field_data.append(u'')
field_change = changed_fields.get(column_name, None)
if not field_change:
continue
new_value = field_change.new
field_data.append(
fields.to_string_representation(field, new_value)
)
return data
def get_export_row(self, serializer, instance):
results = []
representation = serializer.to_representation(instance=instance)
for column_name, value in representation.items():
field = serializer.fields[column_name]
val = fields.to_string_representation(field, value)
# TODO: Excel escaping should be done for Excel/CSV formats
results.append(strings.excel_escape(val))
return results
def might_have_changes(serializer):
submitted_fields = [
(field_name, field)
for field_name, field in serializer.fields.items()
if field_name in serializer.initial_data
and not field.read_only and not field.write_only
]
rep = serializer.to_representation(serializer.instance)
initial = {
field_name: fields.to_string_representation(
field, serializer.initial_data[field_name]
)
for field_name, field in submitted_fields
}
result = {
field_name: fields.to_string_representation(field, rep[field_name])
for field_name, field in submitted_fields
}
return result != initial
