Function _raise_invalid

dash/_validate.py:219–257

(bad_val, outer_val, path, index=None, toplevel=False)

    valid_props = (str, int, float, type(None), tuple, MutableSequence, NoUpdate)

    def _raise_invalid(bad_val, outer_val, path, index=None, toplevel=False):
        bad_type = type(bad_val).__name__
        outer_id = f"(id={outer_val.id:s})" if getattr(outer_val, "id", False) else ""
        outer_type = type(outer_val).__name__
        if toplevel:
            location = dedent(
                """
                The value in question is either the only value returned,
                or is in the top level of the returned list,
                """
            )
        else:
            index_string = "[*]" if index is None else f"[{index:d}]"
            location = dedent(
                f"""
                The value in question is located at
                {index_string} {outer_type} {outer_id}
                {path},
                """
            )

        obj = "tree with one value" if not toplevel else "value"
        raise exceptions.InvalidCallbackReturnValue(
            dedent(
                f"""
                The callback for `{output!r}`
                returned a {obj:s} having type `{bad_type}`
                which is not JSON serializable.

                {location}
                and has string representation
                `{bad_val}`

                In general, Dash properties can only be
                dash components, strings, dictionaries, numbers, None,
                or lists of those.
                """
            )
        )

    def _valid_child(val):
        return isinstance(val, valid_children)