fix nested serializers

Author: nxexox

docs/release-notes.md

@@ -9,15 +9,21 @@ Medium version numbers (0.x.0) may include API changes, in line with the [deprec
 Major version numbers (x.0.0) are reserved for substantial project milestones.
 
 
+### 0.3.14
+
+**Date:** [18th June 2019]
+
+* Fix required nested serializers
+
 ### 0.3.13
 
 **Date:** [2nd April 2020]
 
 * Added check on `None` in `to_representation` methods in:
-    * ['CharField'][CharField]
-    * ['IntegerField'][IntegerField]
-    * ['FloatField'][FloatField]
-    * ['DictField'][DictField]
+    * [`CharField`][CharField]
+    * [`IntegerField`][IntegerField]
+    * [`FloatField`][FloatField]
+    * [`DictField`][DictField]
 
 ### 0.3.12
 

rest_framework/__init__.py

@@ -8,12 +8,12 @@
          __/ |
         |___/
 """
-VERSION = (0, 3, 13)
+VERSION = (0, 3, 14)
 
 __title__ = 'Python-Rest-Framework'
 __author__ = 'Deys Timofey'
 __email__ = '[email protected]'
-__copyright__ = 'Copyright (c) 2019 Deys Timofey'
+__copyright__ = 'Copyright (c) 2020 Deys Timofey'
 __license__ = 'Apache License 2.0'
 __url__ = 'https://github.com/nxexox/python-rest-framework'
 __version__ = '.'.join(map(str, VERSION))

rest_framework/serializers/serializers.py

@@ -131,7 +131,9 @@ def __new__(cls, *args, **kwargs):
         return super(BaseSerializer, cls).__new__(cls)
 
     def __deepcopy__(self, memo={}):
-        return self.__class__(instance=self.instance, data=self.data, source=self.source, allow_none=self.allow_none)
+        return self.__class__(instance=self.instance, data=self.data,
+                              source=self.source, allow_none=self.allow_none,
+                              required=self.required)
 
     @classmethod
     def many_init(cls, *args, **kwargs):
@@ -384,8 +386,15 @@ def _field_validation(self, fields_dict, data):
         for _, field_obj in six.iteritems(fields_dict):
             field_name = field_obj._get_field_name()
             try:
+                # Check by empty for nested serializer fields
+                is_empty, _field_data = field_obj.validate_empty_values(data.get(field_name, None))
+                if is_empty:
+                    if field_name in data:
+                        validated_data[field_name] = _field_data
+                    continue
+
                 # Transform to python type and validate each field.
-                validated_val = field_obj.run_validation(data.get(field_name, None))
+                validated_val = field_obj.run_validation(_field_data)
 
                 # Now manual validation.
                 validated_val = self._manual_validate_method(field_name, validated_val)
@@ -538,7 +547,8 @@ def __deepcopy__(self, memo={}):
         return self.__class__(
             instance=self.instance, data=self.data,
             child=self.child, allow_empty=self.allow_empty,
-            source=self.source, allow_none=self.allow_none
+            source=self.source, allow_none=self.allow_none,
+            required=self.required
         )
 
     def to_internal_value(self, data):