保存表单时出现 Django 完整性错误

Question

我扩展了 Django 用户模型并添加了自己的字段，目前正在努力在注册期间填写这些字段。表单似乎工作正常，除了保存之外的所有内容。

我使用了this 来帮助我。

这是用户模型的扩展：

class StudentProfile(models.Model):
    user = models.OneToOneField(User, null = True, related_name='user', on_delete=models.CASCADE)
    teacher = models.BooleanField(default = False)
    school = models.CharField(max_length = 50)

def create_StudentProfile(sender, **kwargs):
    if kwargs['created']:
        user_profile = StudentProfile.objects.create(user = kwargs['instance'])


post_save.connect(create_StudentProfile, sender = User)

这是我的表格：

class StudentRegistrationForm(UserCreationForm):
    email = forms.EmailField(required = True)
    school = forms.CharField(required = True)

    def __init__(self, *args, **kwargs):
        super(StudentRegistrationForm, self).__init__(*args, **kwargs)
        self.fields['username'].help_text = ''
        self.fields['password2'].help_text = ''


    class Meta:
        model = User

        fields = (
            'username',
            'first_name',
            'last_name',
            'email',
            'school',
            'password1',
            'password2'            
        )

    def save(self, commit = True):
        user = super(StudentRegistrationForm, self).save(commit = False)
        user.first_name = self.cleaned_data['first_name']
        user.last_name = self.cleaned_data['last_name']
        user.email = self.cleaned_data['email']


        student_profile = StudentProfile(user = user, school = self.cleaned_data['school'])

        if commit:
            user.save()
            student_profile.save()

        return user, student_profile

这是我的看法：

def registration(request):
    if request.method == 'POST':
        form = StudentRegistrationForm(request.POST)
        if form.is_valid():
            user, user_profile = form.save(commit = False)
            form.save()
            return render(request, 'accounts/home.html')
        else:
            args = {'form': form}
            return render(request, 'accounts/reg_form.html', args)

    else:
        form = StudentRegistrationForm()

        args = {'form': form}
        return render(request, 'accounts/reg_form.html', args)

这是我的回溯：

File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/django/db/backends/utils.py" in execute
  64.                 return self.cursor.execute(sql, params)

File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/django/db/backends/sqlite3/base.py" in execute
  337.         return Database.Cursor.execute(self, query, params)

The above exception (NOT NULL constraint failed: userprofile_studentprofile.user_id) was the direct cause of the following exception:

File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/django/core/handlers/exception.py" in inner
  39.             response = get_response(request)

File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/django/core/handlers/base.py" in _get_response
  187.                 response = self.process_exception_by_middleware(e, request)

File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/django/core/handlers/base.py" in _get_response
  185.                 response = wrapped_callback(request, *callback_args, **callback_kwargs)

File "/Users/wtreston/GDrive/LesRev/lesssonreview/userprofile/views.py" in registration
  13.             form.save()

File "/Users/wtreston/GDrive/LesRev/lesssonreview/userprofile/forms.py" in save
  41.             student_profile.save()

File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/django/db/models/base.py" in save
  796.                        force_update=force_update, update_fields=update_fields)

File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/django/db/models/base.py" in save_base
  824.             updated = self._save_table(raw, cls, force_insert, force_update, using, update_fields)

File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/django/db/models/base.py" in _save_table
  908.             result = self._do_insert(cls._base_manager, using, fields, update_pk, raw)

File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/django/db/models/base.py" in _do_insert
  947.                                using=using, raw=raw)

File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/django/db/models/manager.py" in manager_method
  85.                 return getattr(self.get_queryset(), name)(*args, **kwargs)

File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/django/db/models/query.py" in _insert
  1045.         return query.get_compiler(using=using).execute_sql(return_id)

File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/django/db/models/sql/compiler.py" in execute_sql
  1054.                 cursor.execute(sql, params)

File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/django/db/backends/utils.py" in execute
  79.             return super(CursorDebugWrapper, self).execute(sql, params)

File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/django/db/backends/utils.py" in execute
  64.                 return self.cursor.execute(sql, params)

File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/django/db/utils.py" in __exit__
  94.                 six.reraise(dj_exc_type, dj_exc_value, traceback)

File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/django/utils/six.py" in reraise
  685.             raise value.with_traceback(tb)

File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/django/db/backends/utils.py" in execute
  64.                 return self.cursor.execute(sql, params)

File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/django/db/backends/sqlite3/base.py" in execute
  337.         return Database.Cursor.execute(self, query, params)

Exception Type: IntegrityError at /users/
Exception Value: NOT NULL constraint failed: userprofile_studentprofile.user_id

谢谢！

Answer 1

您必须使用User 模型创建一个用户，然后您必须将此用户传递给StudentProfile，因为它是一个onetoone 字段给您StudentProfile。

def save(self, request):
        form = StudentRegistrationForm(request.POST)
        user = User.objects.create(first_name=form.cleaned_data['first_name'],
                            last_name=form.cleaned_data['last_name'],
                            email=form.cleaned_data['email'],
                            username=form.cleaned_data['username'])
        user_profile = StudentProfile.objects.create(user=user,
                                                teacher=form.cleaned_data['teacher'],
                                                school=form.cleaned_data['school'])


        return user, student_profile

Answer 2

看起来use对象没有被保存，所以它可以存储它的引用StudentProfile模型。

Answer 3

这里有很多问题。

直接的问题是您要在两个地方创建 UserProfile。您已经注册了一个信号处理程序 - create_StudentProfile - 在创建用户时自动创建一个；但您也在表单的 save 方法中创建一个新的。

您应该考虑是否真的需要该信号处理程序。如果您总是要通过此表单创建用户，则不需要该处理程序。

如果您确实决定需要该信号，那么您需要重做保存方法以将其考虑在内。比如：

def save(self, commit=True):
    user = super(StudentRegistrationForm, self).save(commit = False)
    if commit:
        user.save()
        profile = user.userprofile
    else:
        profile = UserProfile(user=user)

    profile.school = self.cleaned_data['school']

    if commit:
        profile.save()

    return user, student_profile

您会注意到不需要设置电子邮件和姓名，因为这些都是通过超级调用中的表单完成的。

第二个问题是您在视图中调用了两次 save 方法。不要那样做。

    if form.is_valid():
        user, user_profile = form.save()
        return render(request, 'accounts/home.html')