forms.py 文件源码

def clean_username(self):
        username = self.cleaned_data['username']
        norm_username = Poster.normalize_username(username)
        forbidden_names = {
            Poster.normalize_username(utils.get_config('junk_user_username')),
            Poster.normalize_username(utils.get_config('system_user_username'))
        }

        if norm_username in forbidden_names:
            raise ValidationError('You may not register that username.',
                                  code='FORBIDDEN_USERNAME')

        if len(norm_username) < 1:
            raise ValidationError('Invalid username', code='INVALID_GENERAL')

        if Poster.objects.filter(normalized_username=norm_username).count():
            raise ValidationError(
                'User with a similar username already exists',
                code='TOO_SIMILAR')

        return username