Class NestedBoundField

rest_framework/utils/serializer_helpers.py:114–147

This `BoundField` additionally implements __iter__ and __getitem__ in order to support nested bound fields. This class is the type of `BoundField` that is used for serializer fields.

class NestedBoundField(BoundField):
    """
    This `BoundField` additionally implements __iter__ and __getitem__
    in order to support nested bound fields. This class is the type of
    `BoundField` that is used for serializer fields.
    """

    def __init__(self, field, value, errors, prefix=''):
        if value is None or value == '' or not isinstance(value, Mapping):
            value = {}
        super().__init__(field, value, errors, prefix)

    def __iter__(self):
        for field in self.fields.values():
            yield self[field.field_name]

    def __getitem__(self, key):
        field = self.fields[key]
        value = self.value.get(key) if self.value else None
        error = self.errors.get(key) if isinstance(self.errors, dict) else None
        if hasattr(field, 'fields'):
            return NestedBoundField(field, value, error, prefix=self.name + '.')
        elif getattr(field, '_is_jsonfield', False):
            return JSONBoundField(field, value, error, prefix=self.name + '.')
        return BoundField(field, value, error, prefix=self.name + '.')

    def as_form_field(self):
        values = {}
        for key, value in self.value.items():
            if isinstance(value, (list, dict)):
                values[key] = value
            else:
                values[key] = '' if (value is None or value is False) else force_str(value)
        return self.__class__(self._field, values, self.errors, self._prefix)


class BindingDict(MutableMapping):