choice 값 검증 필드(이미 django 에 구현 돼 있지만, 기록을 위해 남겨둠)

customField.py

from django.db import models

class ChoicesValidator:
    def __init__(self, choices):
        self.choices = choices

    def __call__(self, value):
        choice_values = [t[0] for t in self.choices]
        if value not in choice_values:
            from django.core.exceptions import ValidationError
            raise ValidationError(
                'API Method "{}" is not one of the permitted values: {}'.format(
                    value,
                    ', '.join(choice_values)))


class SelectableCharField(models.CharField):

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.validators.append(ChoicesValidator(self.choices))