A dynamic runtime typing validation for members annotated with PEP 484 type hints.

TangoMan PyValidator idea was inspired by agronholm / typeguard but enforces SOLID principles, and is based on the chain-of-responsibility design pattern which makes it more readable, extensible and maintenable.

TangoMan PyValidator provides @Validator.type_check decorator as a mean to dynamically check for type violations at runtime.

Enter following command to install locally

$ sudo python3 setup.py install
# or
$ pip3 install git+https://github.com/TangoMan75/pyvalidator

• Validate typing aliases recursively.
• Validate standard python types.
• Validate classes.
• Validate nullable properties.
• Validate not blank properties.

Python utilities to handle reflexion methods on functions.

Import typing module and extend your class with Validator

import typing

from pyvalidator.validator import Validator

class Foobar(Validator):
	# ...

Document your class with appropriate annotations and use @Validator.type_check decorator on your method and properties.

    @property
    def nullable_str(self) -> typing.Optional[str]:
        return self._nullable_str

    @nullable_str.setter
    @Validator.type_check
    def nullable_str(self, nullable_str_: typing.Optional[str]) -> None:
        self._nullable_str = nullable_str_

At runtime if any given argument does not match expected type, Validator will raise a TypeError.

Use @Validator.not_blank decorator on your method and properties.

    @Validator.not_blank
    def divide(self, a: int, b: int) -> None:
    	return a / b

At runtime Validator will raise a ValueError if any given argument is empty i.e:

• bytes equals b''
• bytearray equals bytearray()
• complex equals 0j
• dict equals {}
• float equals 0.0
• frozenset equals frozenset()
• int equals 0
• list equals []
• memoryview equals memoryview(b'')
• range equals range(0)
• set equals set()
• str equals ''
• tuple equals ()

NOTE: "bool" and "type" values excluded, since "not blank" does not make sense with them.

Decorators are chainable, you can use @Validator.type_check and @Validator.not_blank on the same attribute.

    @property
    def email(self) -> typing.Optional[str]:
        return self._email

    @email.setter
    @Validator.type_check
    @Validator.not_blank
    def email(self, email_: typing.Optional[str]) -> None:
        self._email = email_

typing.OrderedDict causes AttributeError at runtime (which causes travis ci to fail):

AttributeError: module 'typing' has no attribute 'OrderedDict'

Seems like mypy maintainers don't want to fix the issue python/mypy#6904

If you find any bug please report here : Issues

Copyrights (c) 2020 "Matthias Morin" <[email protected]>

Distributed under the MIT license.

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