管理页面中的额外引发错误答案

【问题标题】：Extra raise error in admin page管理页面中的额外引发错误
【发布时间】：2017-07-31 21:47:58
【问题描述】：

当我尝试编辑时，我的管理页面出现问题。在下图中，您可以看到它（额外行中的“必填字段”）。当我尝试编辑时，我看到了额外的一行。我有点用我自己的表单自定义会员块，因为我想在“角色”字段中只向管理员显示“经理”值。它有效，但编辑引发错误。顺便说一句，尽管有多余的行，但我不使用自定义表单编辑工作时没有问题。在下面你可以看到我的代码。所以我对此感到困惑。我怎么解决这个问题？我也尝试以__init__ 这个self.fields['user'].required = False 和self.fields['role'].required = False 的形式使用，但它没有帮助。

models.py：

class Project(models.Model):
    ***FIELDS***
    members = models.ManyToManyField(User, through='Membership',)


ROLE_CHOICES = (
        ('manager', 'Manager'),
        ('developer', 'Developer'),
        ('business_analyst', 'Business analyst'),
        ('system_analysts', 'System analysts'),
)


class Membership (models.Model):
    user = models.ForeignKey(User, on_delete=models.CASCADE)
    project = models.ForeignKey(Project, on_delete=models.CASCADE)
    role = models.CharField(max_length=20, choices=ROLE_CHOICES,)

admin.py：

class MembershipInline(admin.TabularInline):
    model = Membership
    form = MembershipAdminForm
    extra = 1


class MembershipAdmin(admin.ModelAdmin):
    inlines = (MembershipInline,)

admin.site.register(Project, MembershipAdmin)

forms.py：

class MembershipAdminForm(forms.ModelForm):
    class Meta:
        model = Membership
        fields = '__all__'

    def __init__(self, *args, **kwargs):
        super(MembershipAdminForm, self).__init__(*args, **kwargs)
        self.fields['role'].choices = tuple(choice for choice in ROLE_CHOICES if choice[0] not in ['developer', 'business_analyst', 'system_analysts'])

错误：

Traceback (most recent call last):
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\core\handlers\exception.py", line 39, in inner
    response = get_response(request)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\core\handlers\base.py", line 187, in _get_response
    response = self.process_exception_by_middleware(e, request)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\core\handlers\base.py", line 185, in _get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\contrib\admin\options.py", line 544, in wrapper
    return self.admin_site.admin_view(view)(*args, **kwargs)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\utils\decorators.py", line 149, in _wrapped_view
    response = view_func(request, *args, **kwargs)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\views\decorators\cache.py", line 57, in _wrapped_view_func
    response = view_func(request, *args, **kwargs)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\contrib\admin\sites.py", line 211, in inner
    return view(request, *args, **kwargs)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\contrib\admin\options.py", line 1512, in change_view
    return self.changeform_view(request, object_id, form_url, extra_context)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\utils\decorators.py", line 67, in _wrapper
    return bound_func(*args, **kwargs)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\utils\decorators.py", line 149, in _wrapped_view
    response = view_func(request, *args, **kwargs)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\utils\decorators.py", line 63, in bound_func
    return func.__get__(self, type(self))(*args2, **kwargs2)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\contextlib.py", line 30, in inner
    return func(*args, **kwds)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\contrib\admin\options.py", line 1450, in changeform_view
    self.save_related(request, form, formsets, not add)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\contrib\admin\options.py", line 1031, in save_related
    self.save_formset(request, form, formset, change=change)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\contrib\admin\options.py", line 1019, in save_formset
    formset.save()
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\forms\models.py", line 651, in save
    return self.save_existing_objects(commit) + self.save_new_objects(commit)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\forms\models.py", line 784, in save_new_objects
    self.new_objects.append(self.save_new(form, commit=commit))
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\forms\models.py", line 928, in save_new
    obj.save()
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\db\models\base.py", line 796, in save
    force_update=force_update, update_fields=update_fields)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\db\models\base.py", line 824, in save_base
    updated = self._save_table(raw, cls, force_insert, force_update, using, update_fields)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\db\models\base.py", line 908, in _save_table
    result = self._do_insert(cls._base_manager, using, fields, update_pk, raw)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\db\models\base.py", line 947, in _do_insert
    using=using, raw=raw)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\db\models\manager.py", line 85, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\db\models\query.py", line 1045, in _insert
    return query.get_compiler(using=using).execute_sql(return_id)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\db\models\sql\compiler.py", line 1054, in execute_sql
    cursor.execute(sql, params)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\db\backends\utils.py", line 79, in execute
    return super(CursorDebugWrapper, self).execute(sql, params)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\db\backends\utils.py", line 64, in execute
    return self.cursor.execute(sql, params)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\db\utils.py", line 94, in __exit__
    six.reraise(dj_exc_type, dj_exc_value, traceback)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\utils\six.py", line 685, in reraise
    raise value.with_traceback(tb)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\db\backends\utils.py", line 64, in execute
    return self.cursor.execute(sql, params)
  File "C:\Users\Nurzhan\AppData\Local\Programs\Python\Python35-32\lib\site-packages\sql_server\pyodbc\base.py", line 539, in execute
    return self.cursor.execute(sql, params)
django.db.utils.IntegrityError: ('23000', '[23000] [Microsoft][ODBC SQL Server Driver][SQL Server]�� ������� �������� �������� NULL � ������� "user_id", ������� "RMS.dbo.project_membership"; � ������� ��������� �������� NULL. ������ � INSERT. (515) (SQLExecDirectW)')
[10/Mar/2017 20:13:34] "POST /ru/admin/project/project/3/change/ HTTP/1.1" 500 209512

【问题讨论】：

在模型中的字段中使用 blank=True ！
我也试过了，但尝试保存时出现错误。看我的帖子，我用完整的回溯更新它。您还有其他想法吗？
你的模型同步了吗？

标签： python django python-3.x django-forms django-admin

【解决方案1】：

将blank=True 和null=True 添加到您希望成为可选的字段中：

class Membership (models.Model):
    user = models.ForeignKey(User, on_delete=models.CASCADE, blank=True, null=True)
    project = models.ForeignKey(Project, on_delete=models.CASCADE)
    role = models.CharField(max_length=20, choices=ROLE_CHOICES, blank=True, null=True)

【讨论】：

我也试过了，但是会报错。看我的帖子，我用完整的回溯更新它。你有什么想法吗？！
您在进行更改后迁移了吗？
当然，我做到了。
尝试将null=True也添加到字段中
这是不正确的，因为每次我尝试编辑时都有多余的行和空对象。我用图片更新我的帖子。请看一下。

【解决方案2】：

好吧，毕竟我在 Django 的官方文档中找到了解决方案。在我的管理员中。 py 文件我添加了max_num = 1。

如果max_num的值大于现有的相关数对象，最多额外的额外空白表格将添加到 formset，只要表单总数不超过max_num

class MembershipInline(admin.TabularInline):
    model = Membership
    form = MembershipAdminForm
    extra = 1
    max_num = 1

【讨论】：