WTForms 自定义验证器 - 需要在 RadioField 上

Question

我借用了一个验证器，如果另一个字段的值为某个值，则要求用户输入数据：

class RequiredIf(object):
    def __init__(self, *args, **kwargs):
            self.conditions = kwargs
    def __call__(self, form, field):
            for name, data in self.conditions.items():
                if name not in form._fields:
                    Optional(form, field)
                else:
                    condition_field = form._fields.get(name)
                if condition_field.data == data and not field.data:
                    DataRequired()(form, field)
                    Optional()(form, field)

当包含validator 参数的字段是TextField 时，这非常有效，但当字段是RadioField 时，它似乎不起作用。如何调整验证器以便它也适用于 RadioFields？

就目前而言，无论验证条件是否适用，总是为 RadioField 返回not a valid choice。

提前致谢。

例如：

class new_form(Form):
    code=BooleanField('Do you code?')
    code2=RadioField('If so, what languages do you use?',
        choices=[('python','python'),('C++','C++')],
        validators=[RequiredIf(code=1)])

无论是否检查 BooleanField code，this is not a valid choice 始终为 code2 返回。我想要一个验证器，它需要任何类型的字段（包括 RadioField）的输入，以另一个字段的值为条件（在这种情况下为code=1）。

Answer 1

更新！。您可以使用__call__ 创建任何自定义处理。示例：

from multidict import CIMultiDict
from wtforms import Form, RadioField, BooleanField


class RequiredIf(object):

    def __init__(self, **kwargs):
        self.conditions = kwargs

    def __call__(self, form, field):
        # NOTE! you can create here any custom processing
        current_value = form.data.get(field.name)
        if current_value == 'None':
            for condition_field, reserved_value in self.conditions.items():
                dependent_value = form.data.get(condition_field)
                if condition_field not in form.data:
                    continue
                elif dependent_value == reserved_value:
                    # just an example of error
                    raise Exception(
                        'Invalid value of field "%s". Field is required when %s==%s' % (
                            field.name,
                            condition_field,
                            dependent_value
                        ))

class NewForm(Form):
    code = BooleanField('Do you code?')
    code2 = RadioField(
        'If so, what languages do you use?',
        choices=[('python', 'python'), ('C++', 'C++')],
        validators=[RequiredIf(code=True)])

form = NewForm(formdata=CIMultiDict(code=True, code2='python'), )
form.validate()  # valid data - without errors

# invalid data
form = NewForm(formdata=CIMultiDict(code=True), )
form.validate()  # invalid data - Exception: Invalid value of field "code2". Field is required when code==True

再举一个例子，2 RadioField：

class NewForm(Form):
    list_one = RadioField('City/Country', choices=['city', 'country'])
    list_two = RadioField(
        'Cities',
        choices=[('minsk', 'Minsk'), ('tbilisi', 'Tbilisi')],
        validators=[RequiredIf(list_one='city')])


form = NewForm(formdata=CIMultiDict(list_one='city', list_two='minsk'), )
form.validate()  # without errors
form = NewForm(formdata=CIMultiDict(list_one='country'), )
form.validate()  # without errors
form = NewForm(formdata=CIMultiDict(list_one='city'), )
form.validate()  # invalid data - Exception: Invalid value of field "list_two". Field is required when list_one==city

希望这会有所帮助。