def get_default_serializer(class_attribute=None, format=None, value=None):
"""Retrieve the default ``on_serialize`` function that applies to the data
type of ``class_attribute``.
.. note::
If ``class_attribute`` does not have a SQLAlchemy data type, then
determines the data type based on ``value``.
:param class_attribute: The class attribute whose default serializer will be
returned. Defaults to :obj:`None <python:None>`.
:param format: The format to which the value should be serialized. Accepts
either: ``csv``, ``json``, ``yaml``, or ``dict``. Defaults to :obj:`None <python:None>`.
:type format: :class:`str <python:str>`
:param value: The class attribute's value.
:returns: The default :term:`serializer function` to apply or :obj:`None <python:None>`
:rtype: callable / :obj:`None <python:None>`
:raises InvalidFormatError: if ``format`` is not a valid format type
"""
format_to_tuple(format)
format = format.lower()
class_type_key = get_class_type_key(class_attribute, value)
serializer_dict = DEFAULT_SERIALIZERS.get(class_type_key, None)
if serializer_dict is None:
return None
return serializer_dict.get(format, None)
def test_get_class_type_key(request, model_complex_postgresql, attribute,
value, expected_result):
target = model_complex_postgresql[0]
if attribute is not None:
attribute = getattr(target, attribute)
result = get_class_type_key(attribute, value=value)
assert result == expected_result