提交空字段提示KeyError而不是ValidationError

Question

原问题：自定义表单验证错误的呈现方式与 Django 呈现的不同

参考下图，我很难从资源和 Django 的源代码中弄清楚为什么我们自己（来自我们自己的清理/验证）引发的 ValidationError 与表单（Django）呈现的 ValidationError 不同本身。由 Django 引发的字段 ValidationErrors 呈现在“浮动气泡”中，而我引发的 ValidationErrors 呈现为红色文本。

我用来引发 ValidationErrors 的方法是根据 Django 的文档 here，而我在模板中呈现表单的方式只是通过调用 Django 的模板引擎提供的 {{form}} - 尽管也使用 crispy 但是我已经验证，除了将错误消息设置为红色而不是字段下的普通粗体黑色文本之外，它在这里没有任何作用。

理想情况下，我想知道如何或应该做什么，以使所有 ValidationError（Django 的默认值和我自己的）统一显示，以防止表单中跨字段的设计不一致。最好是红色文本。非常感谢我能得到的任何帮助！

表单中的错误图片

表格

# EXAMPLE
class AbstractUserForm(forms.ModelForm):
    
    mail = forms.EmailField()
    mobile = forms.CharField(
        widget=forms.NumberInput,
        required=True
    )

    class Meta:
        model = User
        fields = ['mail', 'mobile']
    
    # validate phone number
    def clean_mobile(self):
        mobile = self.cleaned_data['mobile']
        if len(mobile) < 10 or len(mobile) > 11:
           raise forms.ValidationError("Please put in a valid local phone number")
        return mobile

模板

{% load crispy_forms_tags %}
<!-- make content override base.html's content section-->
{% block content %}
    <div class="content-section">
        <form method="POST">
            {% csrf_token %}
            <fieldset class="form-group">
                <legend class="border-bottom mb-4">
                    User
                </legend>
                {{ form|crispy }}
            </fieldset>
        </form>
    </div>
{% endblock content %}

型号

# EXAMPLE
class LdapUser(ldapdb.models.Model):
    # LDAP meta-data
    base_dn = settings.LDAPUSER_BASE_DN
    object_classes = ['inetOrgPerson', 'person']

    # person
    username = fields.CharField(db_column='cn', primary_key=True)
    given_name = fields.CharField(db_column='givenName')
    user_password = fields.CharField(null=True, db_column='userPassword')
    mobile = fields.CharField(db_column='mobile')

    # inetOrgPerson
    display_name = fields.CharField(db_column='displayName')
    mail = fields.CharField(db_column='mail', unique=True)

更新

根据@abdul-aziz-barkat 的说明-我通过在表单标签中添加novalidate 进行了一些测试。我注意到在不填写某些字段的情况下提交表单可以按预期工作（ValidationErrors 可能由 Django 的默认验证提示为红色），但不是专门针对我表单中的两个字段 - username 和 mail。将这两个字段中的任何一个留空将导致KeyError 'required' 而DEBUG=True

参考图片：

与其他字段相比，这两个字段唯一不同的是username 具有primary_key=True，而mail 具有unique=True 作为models 中的参数。我的模型也是django-ldapdb 的扩展，但我认为这与我的问题没有任何关系。

我已经尝试自己验证它们，但收到了类似的结果

# EXAMPLE
class validate_ldap_required_fields():
    def username(username):
        if username is not None:
            True
        else:
            False

def clean_username(self):
    username = self.cleaned_data['username']
    if not validate_fields.username(username):
        raise forms.ValidationError("This field is required.")
    return username

我也尝试在模型中添加blank=False 作为他们的参数，也收到了类似的结果。

KeyError 追溯

Environment:

Request Method: POST
Request URL: http://host.domain.com/user/new/

Django Version: 3.1.5
Python Version: 3.9.5
Installed Applications:
['mydjangoapp.apps.MyDjangoAppConfig',
 'crispy_forms',
 'django.contrib.admin',
 'django.contrib.auth',
 'django.contrib.contenttypes',
 'django.contrib.sessions',
 'django.contrib.messages',
 'django.contrib.staticfiles']
Installed Middleware:
['django.middleware.security.SecurityMiddleware',
 'django.contrib.sessions.middleware.SessionMiddleware',
 'django.middleware.common.CommonMiddleware',
 'django.middleware.csrf.CsrfViewMiddleware',
 'django.contrib.auth.middleware.AuthenticationMiddleware',
 'django.contrib.messages.middleware.MessageMiddleware',
 'django.middleware.clickjacking.XFrameOptionsMiddleware']



Traceback (most recent call last):
  File "/usr/local/lib/python3.9/site-packages/django/core/handlers/exception.py", line 47, in inner
    response = get_response(request)
  File "/usr/local/lib/python3.9/site-packages/django/core/handlers/base.py", line 181, in _get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)
  File "/usr/local/lib/python3.9/site-packages/django/views/generic/base.py", line 70, in view
    return self.dispatch(request, *args, **kwargs)
  File "/vikings/vikingsldap/views.py", line 71, in dispatch
    return super(UserAccessMixin, self).dispatch(request, *args, **kwargs)
  File "/usr/local/lib/python3.9/site-packages/django/contrib/auth/mixins.py", line 85, in dispatch
    return super().dispatch(request, *args, **kwargs)
  File "/usr/local/lib/python3.9/site-packages/django/views/generic/base.py", line 98, in dispatch
    return handler(request, *args, **kwargs)
  File "/usr/local/lib/python3.9/site-packages/django/views/generic/edit.py", line 172, in post
    return super().post(request, *args, **kwargs)
  File "/usr/local/lib/python3.9/site-packages/django/views/generic/edit.py", line 141, in post
    if form.is_valid():
  File "/usr/local/lib/python3.9/site-packages/django/forms/forms.py", line 177, in is_valid
    return self.is_bound and not self.errors
  File "/usr/local/lib/python3.9/site-packages/django/forms/forms.py", line 172, in errors
    self.full_clean()
  File "/usr/local/lib/python3.9/site-packages/django/forms/forms.py", line 374, in full_clean
    self._clean_fields()
  File "/usr/local/lib/python3.9/site-packages/django/forms/forms.py", line 392, in _clean_fields
    value = field.clean(value)
  File "/usr/local/lib/python3.9/site-packages/django/forms/fields.py", line 150, in clean
    self.validate(value)
  File "/usr/local/lib/python3.9/site-packages/django/forms/fields.py", line 128, in validate
    raise ValidationError(self.error_messages['required'], code='required')

Exception Type: KeyError at /user/new/
Exception Value: 'required'

Answer 1

浮动气泡中的那些错误不是由 Django 呈现的（您的自定义错误和 Django 的默认错误都会像您看到的红色错误一样呈现），那是您的 浏览器 执行了一些验证它自己的。您可以通过在表单标签上添加novalidate 属性来告诉您的浏览器不执行此验证：

<form method="POST" novalidate>