Source code for validators.utils

import inspect
import itertools
from collections import OrderedDict

import six
from decorator import decorator

[docs]class ValidationFailure(object): def __init__(self, func, args): self.func = func self.__dict__.update(args) def __repr__(self): return u'ValidationFailure(func={func}, args={args})'.format( func=self.func.__name__, args=dict( [(k, v) for (k, v) in self.__dict__.items() if k != 'func'] ) ) def __str__(self): return repr(self) def __unicode__(self): return repr(self) def __bool__(self): return False def __nonzero__(self): return False
def func_args_as_dict(func, args, kwargs): """ Return given function's positional and key value arguments as an ordered dictionary. """ arg_names = list( OrderedDict.fromkeys( itertools.chain( inspect.getargspec(func)[0], kwargs.keys() ) ) ) return OrderedDict( list(, args)) + list(kwargs.items()) )
[docs]def validator(func, *args, **kwargs): """ A decorator that makes given function validator. Whenever the given function is called and returns ``False`` value this decorator returns :class:`ValidationFailure` object. Example:: >>> @validator ... def even(value): ... return not (value % 2) >>> even(4) True >>> even(5) ValidationFailure(func=even, args={'value': 5}) :param func: function to decorate :param args: positional function arguments :param kwargs: key value function arguments """ def wrapper(func, *args, **kwargs): value = func(*args, **kwargs) if not value: return ValidationFailure( func, func_args_as_dict(func, args, kwargs) ) return True return decorator(wrapper, func)