AlkantarClanX12
Your IP : 3.15.211.71
import warnings
from collections import ChainMap
from functools import partial, partialmethod, wraps
from itertools import chain
from types import FunctionType
from typing import TYPE_CHECKING, Any, Callable, Dict, Iterable, List, Optional, Set, Tuple, Type, Union, overload
from .errors import ConfigError
from .typing import AnyCallable
from .utils import ROOT_KEY, in_ipython
if TYPE_CHECKING:
from .typing import AnyClassMethod
class Validator:
__slots__ = 'func', 'pre', 'each_item', 'always', 'check_fields', 'skip_on_failure'
def __init__(
self,
func: AnyCallable,
pre: bool = False,
each_item: bool = False,
always: bool = False,
check_fields: bool = False,
skip_on_failure: bool = False,
):
self.func = func
self.pre = pre
self.each_item = each_item
self.always = always
self.check_fields = check_fields
self.skip_on_failure = skip_on_failure
if TYPE_CHECKING:
from inspect import Signature
from .config import BaseConfig
from .fields import ModelField
from .types import ModelOrDc
ValidatorCallable = Callable[[Optional[ModelOrDc], Any, Dict[str, Any], ModelField, Type[BaseConfig]], Any]
ValidatorsList = List[ValidatorCallable]
ValidatorListDict = Dict[str, List[Validator]]
_FUNCS: Set[str] = set()
VALIDATOR_CONFIG_KEY = '__validator_config__'
ROOT_VALIDATOR_CONFIG_KEY = '__root_validator_config__'
def validator(
*fields: str,
pre: bool = False,
each_item: bool = False,
always: bool = False,
check_fields: bool = True,
whole: Optional[bool] = None,
allow_reuse: bool = False,
) -> Callable[[AnyCallable], 'AnyClassMethod']:
"""
Decorate methods on the class indicating that they should be used to validate fields
:param fields: which field(s) the method should be called on
:param pre: whether or not this validator should be called before the standard validators (else after)
:param each_item: for complex objects (sets, lists etc.) whether to validate individual elements rather than the
whole object
:param always: whether this method and other validators should be called even if the value is missing
:param check_fields: whether to check that the fields actually exist on the model
:param allow_reuse: whether to track and raise an error if another validator refers to the decorated function
"""
if not fields:
raise ConfigError('validator with no fields specified')
elif isinstance(fields[0], FunctionType):
raise ConfigError(
"validators should be used with fields and keyword arguments, not bare. " # noqa: Q000
"E.g. usage should be `@validator('<field_name>', ...)`"
)
elif not all(isinstance(field, str) for field in fields):
raise ConfigError(
"validator fields should be passed as separate string args. " # noqa: Q000
"E.g. usage should be `@validator('<field_name_1>', '<field_name_2>', ...)`"
)
if whole is not None:
warnings.warn(
'The "whole" keyword argument is deprecated, use "each_item" (inverse meaning, default False) instead',
DeprecationWarning,
)
assert each_item is False, '"each_item" and "whole" conflict, remove "whole"'
each_item = not whole
def dec(f: AnyCallable) -> 'AnyClassMethod':
f_cls = _prepare_validator(f, allow_reuse)
setattr(
f_cls,
VALIDATOR_CONFIG_KEY,
(
fields,
Validator(func=f_cls.__func__, pre=pre, each_item=each_item, always=always, check_fields=check_fields),
),
)
return f_cls
return dec
@overload
def root_validator(_func: AnyCallable) -> 'AnyClassMethod':
...
@overload
def root_validator(
*, pre: bool = False, allow_reuse: bool = False, skip_on_failure: bool = False
) -> Callable[[AnyCallable], 'AnyClassMethod']:
...
def root_validator(
_func: Optional[AnyCallable] = None, *, pre: bool = False, allow_reuse: bool = False, skip_on_failure: bool = False
) -> Union['AnyClassMethod', Callable[[AnyCallable], 'AnyClassMethod']]:
"""
Decorate methods on a model indicating that they should be used to validate (and perhaps modify) data either
before or after standard model parsing/validation is performed.
"""
if _func:
f_cls = _prepare_validator(_func, allow_reuse)
setattr(
f_cls, ROOT_VALIDATOR_CONFIG_KEY, Validator(func=f_cls.__func__, pre=pre, skip_on_failure=skip_on_failure)
)
return f_cls
def dec(f: AnyCallable) -> 'AnyClassMethod':
f_cls = _prepare_validator(f, allow_reuse)
setattr(
f_cls, ROOT_VALIDATOR_CONFIG_KEY, Validator(func=f_cls.__func__, pre=pre, skip_on_failure=skip_on_failure)
)
return f_cls
return dec
def _prepare_validator(function: AnyCallable, allow_reuse: bool) -> 'AnyClassMethod':
"""
Avoid validators with duplicated names since without this, validators can be overwritten silently
which generally isn't the intended behaviour, don't run in ipython (see #312) or if allow_reuse is False.
"""
f_cls = function if isinstance(function, classmethod) else classmethod(function)
if not in_ipython() and not allow_reuse:
ref = (
getattr(f_cls.__func__, '__module__', '<No __module__>')
+ '.'
+ getattr(f_cls.__func__, '__qualname__', f'<No __qualname__: id:{id(f_cls.__func__)}>')
)
if ref in _FUNCS:
raise ConfigError(f'duplicate validator function "{ref}"; if this is intended, set `allow_reuse=True`')
_FUNCS.add(ref)
return f_cls
class ValidatorGroup:
def __init__(self, validators: 'ValidatorListDict') -> None:
self.validators = validators
self.used_validators = {'*'}
def get_validators(self, name: str) -> Optional[Dict[str, Validator]]:
self.used_validators.add(name)
validators = self.validators.get(name, [])
if name != ROOT_KEY:
validators += self.validators.get('*', [])
if validators:
return {getattr(v.func, '__name__', f'<No __name__: id:{id(v.func)}>'): v for v in validators}
else:
return None
def check_for_unused(self) -> None:
unused_validators = set(
chain.from_iterable(
(
getattr(v.func, '__name__', f'<No __name__: id:{id(v.func)}>')
for v in self.validators[f]
if v.check_fields
)
for f in (self.validators.keys() - self.used_validators)
)
)
if unused_validators:
fn = ', '.join(unused_validators)
raise ConfigError(
f"Validators defined with incorrect fields: {fn} " # noqa: Q000
f"(use check_fields=False if you're inheriting from the model and intended this)"
)
def extract_validators(namespace: Dict[str, Any]) -> Dict[str, List[Validator]]:
validators: Dict[str, List[Validator]] = {}
for var_name, value in namespace.items():
validator_config = getattr(value, VALIDATOR_CONFIG_KEY, None)
if validator_config:
fields, v = validator_config
for field in fields:
if field in validators:
validators[field].append(v)
else:
validators[field] = [v]
return validators
def extract_root_validators(namespace: Dict[str, Any]) -> Tuple[List[AnyCallable], List[Tuple[bool, AnyCallable]]]:
from inspect import signature
pre_validators: List[AnyCallable] = []
post_validators: List[Tuple[bool, AnyCallable]] = []
for name, value in namespace.items():
validator_config: Optional[Validator] = getattr(value, ROOT_VALIDATOR_CONFIG_KEY, None)
if validator_config:
sig = signature(validator_config.func)
args = list(sig.parameters.keys())
if args[0] == 'self':
raise ConfigError(
f'Invalid signature for root validator {name}: {sig}, "self" not permitted as first argument, '
f'should be: (cls, values).'
)
if len(args) != 2:
raise ConfigError(f'Invalid signature for root validator {name}: {sig}, should be: (cls, values).')
# check function signature
if validator_config.pre:
pre_validators.append(validator_config.func)
else:
post_validators.append((validator_config.skip_on_failure, validator_config.func))
return pre_validators, post_validators
def inherit_validators(base_validators: 'ValidatorListDict', validators: 'ValidatorListDict') -> 'ValidatorListDict':
for field, field_validators in base_validators.items():
if field not in validators:
validators[field] = []
validators[field] += field_validators
return validators
def make_generic_validator(validator: AnyCallable) -> 'ValidatorCallable':
"""
Make a generic function which calls a validator with the right arguments.
Unfortunately other approaches (eg. return a partial of a function that builds the arguments) is slow,
hence this laborious way of doing things.
It's done like this so validators don't all need **kwargs in their signature, eg. any combination of
the arguments "values", "fields" and/or "config" are permitted.
"""
from inspect import signature
if not isinstance(validator, (partial, partialmethod)):
# This should be the default case, so overhead is reduced
sig = signature(validator)
args = list(sig.parameters.keys())
else:
# Fix the generated argument lists of partial methods
sig = signature(validator.func)
args = [
k
for k in signature(validator.func).parameters.keys()
if k not in validator.args | validator.keywords.keys()
]
first_arg = args.pop(0)
if first_arg == 'self':
raise ConfigError(
f'Invalid signature for validator {validator}: {sig}, "self" not permitted as first argument, '
f'should be: (cls, value, values, config, field), "values", "config" and "field" are all optional.'
)
elif first_arg == 'cls':
# assume the second argument is value
return wraps(validator)(_generic_validator_cls(validator, sig, set(args[1:])))
else:
# assume the first argument was value which has already been removed
return wraps(validator)(_generic_validator_basic(validator, sig, set(args)))
def prep_validators(v_funcs: Iterable[AnyCallable]) -> 'ValidatorsList':
return [make_generic_validator(f) for f in v_funcs if f]
all_kwargs = {'values', 'field', 'config'}
def _generic_validator_cls(validator: AnyCallable, sig: 'Signature', args: Set[str]) -> 'ValidatorCallable':
# assume the first argument is value
has_kwargs = False
if 'kwargs' in args:
has_kwargs = True
args -= {'kwargs'}
if not args.issubset(all_kwargs):
raise ConfigError(
f'Invalid signature for validator {validator}: {sig}, should be: '
f'(cls, value, values, config, field), "values", "config" and "field" are all optional.'
)
if has_kwargs:
return lambda cls, v, values, field, config: validator(cls, v, values=values, field=field, config=config)
elif args == set():
return lambda cls, v, values, field, config: validator(cls, v)
elif args == {'values'}:
return lambda cls, v, values, field, config: validator(cls, v, values=values)
elif args == {'field'}:
return lambda cls, v, values, field, config: validator(cls, v, field=field)
elif args == {'config'}:
return lambda cls, v, values, field, config: validator(cls, v, config=config)
elif args == {'values', 'field'}:
return lambda cls, v, values, field, config: validator(cls, v, values=values, field=field)
elif args == {'values', 'config'}:
return lambda cls, v, values, field, config: validator(cls, v, values=values, config=config)
elif args == {'field', 'config'}:
return lambda cls, v, values, field, config: validator(cls, v, field=field, config=config)
else:
# args == {'values', 'field', 'config'}
return lambda cls, v, values, field, config: validator(cls, v, values=values, field=field, config=config)
def _generic_validator_basic(validator: AnyCallable, sig: 'Signature', args: Set[str]) -> 'ValidatorCallable':
has_kwargs = False
if 'kwargs' in args:
has_kwargs = True
args -= {'kwargs'}
if not args.issubset(all_kwargs):
raise ConfigError(
f'Invalid signature for validator {validator}: {sig}, should be: '
f'(value, values, config, field), "values", "config" and "field" are all optional.'
)
if has_kwargs:
return lambda cls, v, values, field, config: validator(v, values=values, field=field, config=config)
elif args == set():
return lambda cls, v, values, field, config: validator(v)
elif args == {'values'}:
return lambda cls, v, values, field, config: validator(v, values=values)
elif args == {'field'}:
return lambda cls, v, values, field, config: validator(v, field=field)
elif args == {'config'}:
return lambda cls, v, values, field, config: validator(v, config=config)
elif args == {'values', 'field'}:
return lambda cls, v, values, field, config: validator(v, values=values, field=field)
elif args == {'values', 'config'}:
return lambda cls, v, values, field, config: validator(v, values=values, config=config)
elif args == {'field', 'config'}:
return lambda cls, v, values, field, config: validator(v, field=field, config=config)
else:
# args == {'values', 'field', 'config'}
return lambda cls, v, values, field, config: validator(v, values=values, field=field, config=config)
def gather_all_validators(type_: 'ModelOrDc') -> Dict[str, 'AnyClassMethod']:
all_attributes = ChainMap(*[cls.__dict__ for cls in type_.__mro__]) # type: ignore[arg-type,var-annotated]
return {
k: v
for k, v in all_attributes.items()
if hasattr(v, VALIDATOR_CONFIG_KEY) or hasattr(v, ROOT_VALIDATOR_CONFIG_KEY)
}