Function walk_flatten_vs_selector

ormar/models/excludable.py:192–236

Recursive worker behind :meth:`FlattenMap.check_vs_selector` — kept at module level so the recursion stays on a plain dict and does not allocate intermediate :class:`FlattenMap` instances. :param flatten_map: current level of the flatten nested dict :type flatten_map: dict

(
    flatten_map: dict,
    selector: Union[set, dict, None],
    selector_kind: str,
    path: str,
)

def walk_flatten_vs_selector(
    flatten_map: dict,
    selector: Union[set, dict, None],
    selector_kind: str,
    path: str,
) -> None:
    """
    Recursive worker behind :meth:`FlattenMap.check_vs_selector` — kept at
    module level so the recursion stays on a plain dict and does not allocate
    intermediate :class:`FlattenMap` instances.

    :param flatten_map: current level of the flatten nested dict
    :type flatten_map: dict
    :param selector: current level of include / exclude nested dict
    :type selector: Union[set, dict, None]
    :param selector_kind: "include" or "exclude" - used in error message
    :type selector_kind: str
    :param path: dunder path accumulator for the error message
    :type path: str
    """
    if not selector or not isinstance(selector, dict):
        return
    for key, value in flatten_map.items():
        sel = selector.get(key)
        full_path = f"{path}__{key}" if path else key
        if value is Ellipsis:
            conflicts: Optional[set] = None
            if isinstance(sel, dict):
                conflicts = set(sel.keys()) - {...}
            elif isinstance(sel, set):
                conflicts = {item for item in sel if item is not ...}
            if conflicts:
                raise QueryDefinitionError(
                    f"Flatten conflict: relation '{full_path}' is flattened "
                    f"but {selector_kind} specifies children "
                    f"{sorted(conflicts)}. A flattened relation renders only "
                    f"its primary key and cannot have children selected."
                )
        elif isinstance(value, dict):
            walk_flatten_vs_selector(
                flatten_map=value,
                selector=sel,
                selector_kind=selector_kind,
                path=full_path,
            )


@dataclass