Method flatten_fields

ormar/queryset/queryset.py:453–496

Render selected related models as their primary-key value on ``model_dump()`` instead of the default nested dict. Accepts the same input forms as :py:meth:`fields` / :py:meth:`exclude_fields` plus ``FieldAccessor`` / list of accessors. Missing relations are

(
        self,
        columns: Union[list, str, set, tuple, dict, FieldAccessor],
    )

        return self.rebuild_self(prefetch_related=related)

    def flatten_fields(
        self,
        columns: Union[list, str, set, tuple, dict, FieldAccessor],
    ) -> "QuerySet[T]":
        """
        Render selected related models as their primary-key value on
        ``model_dump()`` instead of the default nested dict.

        Accepts the same input forms as :py:meth:`fields` / :py:meth:`exclude_fields`
        plus ``FieldAccessor`` / list of accessors. Missing relations are
        auto-loaded: single-valued foreign keys go into ``select_related``,
        many-to-many and reverse relations into ``prefetch_related``.

        Chained calls merge. A flatten directive conflicts with any include or
        exclude sub-field selection on the same relation (scalar output has no
        place for children).

        :param columns: relations to flatten on serialization
        :type columns: Union[list, str, set, tuple, dict, FieldAccessor]
        :return: new QuerySet with the flatten spec applied
        :rtype: QuerySet[T]
        """
        normalized = extract_access_chains(columns)

        excludable = ormar.ExcludableItems.from_excludable(self._excludable)
        excludable.build(
            items=normalized,
            model_cls=self.model_cls,  # type: ignore
            slot="flatten",
        )
        excludable.validate_flatten_vs_excludable(
            source_model=self.model_cls  # type: ignore
        )

        select_to_add, prefetch_to_add = self._classify_flatten_paths(
            excludable._flatten_paths
        )
        new_select = sorted(set(self._select_related) | select_to_add)
        new_prefetch = sorted(set(self._prefetch_related) | prefetch_to_add)
        return self.rebuild_self(
            excludable=excludable,
            select_related=new_select,
            prefetch_related=new_prefetch,
        )

    def _classify_flatten_paths(
        self, paths: Iterable[tuple[str, ...]]