from dvalidator.validator import Validator
import dvalidator.rules as rules


validator = Validator({
    'a': rules.required(),
    'b': rules.required('Field "b" not found'),
    'c': [rules.required(), rules.is_type(str, 'Field "c" is not str type')]
    })

d = {'a': 1, 'b': 2, 'c': '3'}

res, err = validator.validate(d)

print(res)
True

from dvalidator.validator import Validator
import dvalidator.rules as rules


def raise_on_exist(message='Found unexpected field in dict'):
    def check(field: str, dict_to_check: dict):
        if field in dict_to_check:
            return False, None
        else:
            return True, message
    return check

validator = Validator({
    'a': rules.required(),
    'b': raise_on_exist()
    })

d = {'a': 1, 'b': 2}

res, err = validator.validate(d)

print(res)
False