feat: allow custom (de)normalization (#32)

Signed-off-by: Jan Kowalleck <jan.kowalleck@gmail.com>

serializable/__init__.py

@@ -195,7 +195,8 @@ def default(self, o: Any) -> Any:
 
                 if prop_info.custom_type:
                     if prop_info.is_helper_type():
-                        v = prop_info.custom_type.json_serialize(v)
+                        v = prop_info.custom_type.json_normalize(
+                            v, view=self._view, prop_info=prop_info, ctx=o.__class__)
                     else:
                         v = prop_info.custom_type(v)
                 elif prop_info.is_array:
@@ -298,17 +299,15 @@ def from_json(cls: Type[_T], data: Dict[str, Any]) -> Optional[_T]:
             try:
                 if prop_info.custom_type:
                     if prop_info.is_helper_type():
-                        _data[k] = prop_info.custom_type.json_deserialize(v)
+                        _data[k] = prop_info.custom_type.json_denormalize(
+                            v, prop_info=prop_info, ctx=klass)
                     else:
                         _data[k] = prop_info.custom_type(v)
                 elif prop_info.is_array:
                     items = []
                     for j in v:
                         if not prop_info.is_primitive_type() and not prop_info.is_enum:
-                            try:
-                                items.append(prop_info.concrete_type.from_json(data=j))
-                            except AttributeError as e:
-                                raise e
+                            items.append(prop_info.concrete_type.from_json(data=j))
                         else:
                             items.append(prop_info.concrete_type(j))
                     _data[k] = items  # type: ignore
@@ -438,7 +437,14 @@ def as_xml(self: Any, view_: Optional[Type[ViewType]] = None,
                             SubElement(nested_e, nested_key).text = str(j)
                 elif prop_info.custom_type:
                     if prop_info.is_helper_type():
-                        SubElement(this_e, new_key).text = str(prop_info.custom_type.xml_serialize(v))
+                        v_ser = prop_info.custom_type.xml_normalize(
+                            v, view=view_, element_name=new_key, xmlns=xmlns, prop_info=prop_info, ctx=self.__class__)
+                        if v_ser is None:
+                            pass  # skip the element
+                        elif isinstance(v_ser, Element):
+                            this_e.append(v_ser)
+                        else:
+                            SubElement(this_e, new_key).text = str(v_ser)
                     else:
                         SubElement(this_e, new_key).text = str(prop_info.custom_type(v))
                 elif prop_info.is_enum:
@@ -583,14 +589,16 @@ def strip_default_namespace(s: str) -> str:
                             )
                         elif prop_info.custom_type:
                             if prop_info.is_helper_type():
-                                _data[decoded_k] = prop_info.custom_type.xml_deserialize(child_e)
+                                _data[decoded_k] = prop_info.custom_type.xml_denormalize(
+                                    child_e, default_ns=default_namespace, prop_info=prop_info, ctx=klass)
                             else:
                                 _data[decoded_k] = prop_info.custom_type(child_e.text)
                         else:
                             _data[decoded_k].append(prop_info.concrete_type(child_e.text))
                 elif prop_info.custom_type:
                     if prop_info.is_helper_type():
-                        _data[decoded_k] = prop_info.custom_type.xml_deserialize(child_e.text)
+                        _data[decoded_k] = prop_info.custom_type.xml_denormalize(
+                            child_e, default_ns=default_namespace, prop_info=prop_info, ctx=klass)
                     else:
                         _data[decoded_k] = prop_info.custom_type(child_e.text)
                 elif prop_info.is_enum:

serializable/helpers.py

@@ -16,16 +16,24 @@
 #
 # SPDX-License-Identifier: Apache-2.0
 # Copyright (c) Paul Horton. All Rights Reserved.
+
 import re
 import warnings
 from datetime import date, datetime
-from typing import Any
+from typing import TYPE_CHECKING, Any, Optional, Type, TypeVar, Union
+
+if TYPE_CHECKING:  # pragma: no cover
+    from xml.etree.ElementTree import Element
+
+    from . import ObjectMetadataLibrary, ViewType
+
+_T = TypeVar('_T')
 
 
 class BaseHelper:
     """Base Helper.
 
-    Inherit from this class and implement the needed functions!
+    Inherit from this class and implement/override the needed functions!
 
     This class does not provide any functionality,
     it is more like a Protocol with some fallback implementations.
@@ -34,7 +42,7 @@ class BaseHelper:
     # region general/fallback
 
     @classmethod
-    def serialize(cls, o: Any) -> Any:
+    def serialize(cls, o: Any) -> Union[Any, str]:
         """general purpose serializer"""
         raise NotImplementedError()
 
@@ -48,10 +56,31 @@ def deserialize(cls, o: Any) -> Any:
     # region json specific
 
     @classmethod
-    def json_serialize(cls, o: Any) -> Any:
+    def json_normalize(cls, o: Any, *,
+                       view: Optional[Type['ViewType']],
+                       prop_info: 'ObjectMetadataLibrary.SerializableProperty',
+                       ctx: Type[Any],
+                       **kwargs: Any) -> Optional[Any]:
+        """json specific normalizer"""
+        return cls.json_serialize(o)
+
+    @classmethod
+    def json_serialize(cls, o: Any) -> Union[str, Any]:
         """json specific serializer"""
         return cls.serialize(o)
 
+    @classmethod
+    def json_denormalize(cls, o: Any, *,
+                         prop_info: 'ObjectMetadataLibrary.SerializableProperty',
+                         ctx: Type[Any],
+                         **kwargs: Any) -> Any:
+        """json specific denormalizer
+
+        :param tCls: the class that was desired to denormalize to
+        :param pCls: tha prent class - as context
+        """
+        return cls.json_deserialize(o)
+
     @classmethod
     def json_deserialize(cls, o: Any) -> Any:
         """json specific deserializer"""
@@ -62,12 +91,32 @@ def json_deserialize(cls, o: Any) -> Any:
     # endregion xml specific
 
     @classmethod
-    def xml_serialize(cls, o: Any) -> Any:
+    def xml_normalize(cls, o: Any, *,
+                      element_name: str,
+                      view: Optional[Type['ViewType']],
+                      xmlns: Optional[str],
+                      prop_info: 'ObjectMetadataLibrary.SerializableProperty',
+                      ctx: Type[Any],
+                      **kwargs: Any) -> Optional[Union['Element', Any]]:
+        """xml specific normalizer"""
+        return cls.xml_serialize(o)
+
+    @classmethod
+    def xml_serialize(cls, o: Any) -> Union[str, Any]:
         """xml specific serializer"""
         return cls.serialize(o)
 
     @classmethod
-    def xml_deserialize(cls, o: Any) -> Any:
+    def xml_denormalize(cls, o: 'Element', *,
+                        default_ns: Optional[str],
+                        prop_info: 'ObjectMetadataLibrary.SerializableProperty',
+                        ctx: Type[Any],
+                        **kwargs: Any) -> Any:
+        """xml specific denormalizer"""
+        return cls.xml_deserialize(o.text)
+
+    @classmethod
+    def xml_deserialize(cls, o: Union[str, Any]) -> Any:
         """xml specific deserializer"""
         return cls.deserialize(o)