validator

Decorate methods on the class indicating that they should be used to validate fields.

def validator(
    __field: str,
    *fields: str,
    pre: bool = False,
    each_item: bool = False,
    always: bool = False,
    check_fields: bool | None = None,
    allow_reuse: bool = False
) - > Callable

Decorate methods on the class indicating that they should be used to validate fields.

Parameters

Name	Type	Description
__field	str	The first field the validator should be called on; this is separate from fields to ensure an error is raised if you don't pass at least one.
*fields	str	Additional field(s) the validator should be called on.
pre	bool = False	Whether this validator should be called before the standard validators (else after).
each_item	bool = False	For complex objects (sets, lists etc.) whether to validate individual elements rather than the whole object.
always	bool = False	Whether this method and other validators should be called even if the value is missing.
check_fields	`bool	None` = None
allow_reuse	bool = False	Whether to track and raise an error if another validator refers to the decorated function.

Returns

Type	Description
Callable	A decorator that can be used to decorate a function to be used as a validator.