def build_composite_field(
self, field_name: str, type_info: TypeInfo,
extra_kwargs: KWArgs) -> SerializerFieldDefinition:
"""
Create a composite (mapping or list) field.
"""
# Lookup the types from the field mapping, so that it can easily be changed without overriding the method.
if type_info.is_mapping:
field_class = self.serializer_field_mapping[dict]
else:
field_class = self.serializer_field_mapping[list]
# If the base type is not specified or is any type, we don't have to bother creating the child field.
if type_info.base_type is None:
return field_class, {}
# Recurse to build the child field (i.e. the field of every instance). We pass the extra kwargs that are
# specified for the child field through, so these can be used to recursively specify kwargs for child fields.
extra_child_field_kwargs = extra_kwargs.get('child_kwargs', {})
base_type_info = field_utils.get_type_info(type_info.base_type)
child_field_class, child_field_kwargs = self.build_typed_field(
field_name, base_type_info, extra_child_field_kwargs)
# Include the extra kwargs specified for the child field before instantiating it.
child_field_kwargs = self.include_extra_kwargs(
child_field_kwargs, extra_child_field_kwargs)
# Create child field and initialize parent field kwargs
child_field = child_field_class(**child_field_kwargs)
field_kwargs = {'child': child_field}
return field_class, field_kwargs
def build_composite_field(
self, definition: DataclassDefinition, field_name: str,
type_info: TypeInfo,
extra_kwargs: KWArgs) -> SerializerFieldDefinition:
"""
Create a composite (mapping or list) field.
"""
# Recurse to build the child field (i.e. the field of every instance). We pass the extra kwargs that are
# specified for the child field through, so these can be used to recursively specify kwargs for child fields.
extra_child_field_kwargs = extra_kwargs.get('child_kwargs', {})
base_type_info = field_utils.get_type_info(type_info.base_type)
child_field_class, child_field_kwargs = self.build_typed_field(
definition, field_name, base_type_info, extra_child_field_kwargs)
# Include the extra kwargs specified for the child field before instantiating it.
child_field_kwargs = self.include_extra_kwargs(
child_field_kwargs, extra_child_field_kwargs)
# Create child field and initialize parent field kwargs
child_field = child_field_class(**child_field_kwargs)
field_kwargs = {
'allow_null': type_info.is_optional,
'child': child_field
}
if type_info.is_mapping:
field_class = rest_framework.fields.DictField
else:
field_class = rest_framework.fields.ListField
return field_class, field_kwargs
def create_field(self, field_name: str,
extra_kwargs: KWArgs) -> SerializerField:
# Get the source field (this can be useful to represent a single dataclass field in multiple ways in the
# serialization state).
source = extra_kwargs.get('source', '*')
if source == '*':
source = field_name
# Determine the serializer field class and keyword arguments.
if source in self.dataclass_definition.fields:
default_value = self.dataclass_definition.fields[source].default
default_type = type(
default_value) if default_value is not None else None
type_info = field_utils.get_type_info(
self.dataclass_definition.field_types[source], default_type)
field_class, field_kwargs = self.build_typed_field(
source, type_info, extra_kwargs)
elif hasattr(self.dataclass_definition.dataclass_type, source):
field_class, field_kwargs = self.build_property_field(source)
else:
field_class, field_kwargs = self.build_unknown_field(source)
# Include any extra kwargs defined through `Meta.extra_kwargs`
field_kwargs = self.include_extra_kwargs(field_kwargs, extra_kwargs)
# Create the serializer field instance.
return field_class(**field_kwargs)
def build_typed_field(self, type_hint, extra_kwargs=None):
testclass = dataclasses.make_dataclass('TestDataclass', [('test_field', type_hint)])
serializer = DataclassSerializer(dataclass=testclass)
type_info = field_utils.get_type_info(serializer.dataclass_definition.field_types['test_field'])
extra_kwargs = extra_kwargs or {}
return serializer.build_typed_field('test_field', type_info, extra_kwargs)