maite.utils.validation.chain_validators#

maite.utils.validation.chain_validators(*validators)[source]#

Enable validators to be chained together.

Validators are functions like (name: str, arg: T, [...]) -> T. This is meant to be used with partial’d validators, where only the name and arg fields need be populated.

Parameters:

*validatorsCallable[[str, T], T]: Accepts name and arg, and returns arg if it is a valid input, otherwise should raise InvalidArgument.

Returns:

Callable[[str, T], T]: A function of signature chain(name: str, arg: T) -> T that calls each validator as val(name, arg) in order from low-index to high-index.

Examples

>>> from maite.utils.validation import check_type, check_domain, chain_validators
>>> from functools import partial
>>> is_int = partial(check_type, type_=int)
>>> is_pos = partial(check_domain, lower=0)
>>> check_pos_int = chain_validators(is_int, is_pos)
>>> check_pos_int("foo", 10)
10
>>> try:
...     check_pos_int("foo", ["a"])
... except:
...     print("maite.errors.InvalidArgument: Expected `foo` to be of type `int`. Got `['a']` (type: `list`).")
maite.errors.InvalidArgument: Expected `foo` to be of type `int`. Got `['a']` (type: `list`).
>>> try:
...     check_pos_int("foo", -1)
... except:
...     print("maite.errors.InvalidArgument: `foo` must satisfy `0 <= foo`.  Got: `-1`.")
maite.errors.InvalidArgument: `foo` must satisfy `0 <= foo`.  Got: `-1`.