我如何解决此错误：django.db.utils.IntegrityError：NOT NULL约束失败

如何解决我如何解决此错误：django.db.utils.IntegrityError：NOT NULL约束失败

我正在为我的心愿单按钮/视图编写单元测试，并且试图检查在按下按钮后是否将我的书ISBN和用户ID添加到心愿单中。我已经尝试过了，但是它一直给我标题中指出的错误。

这是我的代码：

#tests.py
class wishlist_view_test(TestCase):
    @classmethod
    def setUpTestData(cls):
        books.objects.create(ISBN = "976354890",bookName = "testingbook1",bookVersion = "1",bookAuthor = "Carlie Presley",bookPublisher = "TeamBananaMonkey1")
        retailer.objects.create(retailer= "Amazon",sellerID = 1)
        retailer_book.objects.create(condition = "new",reviews = "4.5",ID= 1,bookType = "hardcover",ISBN_id= "976354890",sellerID_id = 1,price = 177.98)

    def test_wishlist_button(self):
        user = User.objects.create_user(username='user1',password='djangolife')
        self.client.login(username='user1',password='djangolife')
        response1 = self.client.post(reverse('TextSearch:wishlist',args=("976354890",)))
        self.assertEqual(str(wishlist.objects.filter(userid_id= user.id),'<QuerySet [..........]>')

#html code
<form action="{% url 'TextSearch:wishlist' book.pk %}" method="post">
    {% csrf_token %}
    <input type="hidden" value="{{book.pk}}" name="isbn">
    <input type="submit" value="Add to wishlist★">

#views.py
class wishlistView(TemplateView):
    template_name = 'TextSearch/wishlist.html'
    model = wishlist
    def post(self,request,pk):
        isbn = self.request.POST.get('isbn')
        current_user = request.user
        book = wishlist(userid_id = current_user.id,ISBN_id = isbn)
        book.save()
        return render(request,'TextSearch/wishlist.html')

#models.py
class wishlist (models.Model):
    userid = models.ForeignKey(User,on_delete= models.CASCADE)
    ISBN = models.ForeignKey(books,on_delete = models.CASCADE)

class books (models.Model):
    ISBN = models.CharField(max_length=255,primary_key=True)
    bookName = models.CharField(max_length=255)
    bookVersion = models.CharField(max_length=255)
    bookAuthor = models.CharField(max_length=255)
    bookPublisher = models.CharField(max_length=255,default ='NULL')

我正在使用Django的内置用户模型。

***追溯错误***

Traceback (most recent call last):
  File "C:\Users\ytann\Desktop\textbooks-for-less-9-website-design\textbooks-for-less-9-website-design\TextSearch\tests.py",line 67,in test_wishlist_button
    response1 = self.client.post(reverse('TextSearch:wishlist',)))
  File "C:\Users\ytann\Desktop\python\lib\site-packages\django\test\client.py",line 741,in post
    response = super().post(path,data=data,content_type=content_type,secure=secure,**extra)
  File "C:\Users\ytann\Desktop\python\lib\site-packages\django\test\client.py",line 404,in post
    return self.generic('POST',path,post_data,content_type,File "C:\Users\ytann\Desktop\python\lib\site-packages\django\test\client.py",line 470,in generic
    return self.request(**r)
  File "C:\Users\ytann\Desktop\python\lib\site-packages\django\test\client.py",line 709,in request
    self.check_exception(response)
  File "C:\Users\ytann\Desktop\python\lib\site-packages\django\test\client.py",line 571,in check_exception
    raise exc_value
  File "C:\Users\ytann\Desktop\python\lib\site-packages\django\core\handlers\exception.py",line 47,in inner
    response = get_response(request)
  File "C:\Users\ytann\Desktop\python\lib\site-packages\django\core\handlers\base.py",line 179,in _get_response
    response = wrapped_callback(request,*callback_args,**callback_kwargs)
  File "C:\Users\ytann\Desktop\python\lib\site-packages\django\views\generic\base.py",line 70,in view
    return self.dispatch(request,*args,**kwargs)
  File "C:\Users\ytann\Desktop\python\lib\site-packages\django\views\generic\base.py",line 98,in dispatch
    return handler(request,**kwargs)
  File "C:\Users\ytann\Desktop\textbooks-for-less-9-website-design\textbooks-for-less-9-website-design\TextSearch\views.py",line 25,in post
    book.save()
  File "C:\Users\ytann\Desktop\python\lib\site-packages\django\db\models\base.py",line 753,in save
    self.save_base(using=using,force_insert=force_insert,File "C:\Users\ytann\Desktop\python\lib\site-packages\django\db\models\base.py",line 790,in save_base
    updated = self._save_table(
  File "C:\Users\ytann\Desktop\python\lib\site-packages\django\db\models\base.py",line 895,in _save_table
    results = self._do_insert(cls._base_manager,using,fields,returning_fields,raw)
  File "C:\Users\ytann\Desktop\python\lib\site-packages\django\db\models\base.py",line 933,in _do_insert
    return manager._insert(
  File "C:\Users\ytann\Desktop\python\lib\site-packages\django\db\models\manager.py",line 85,in manager_method
    return getattr(self.get_queryset(),name)(*args,**kwargs)
  File "C:\Users\ytann\Desktop\python\lib\site-packages\django\db\models\query.py",line 1249,in _insert
    return query.get_compiler(using=using).execute_sql(returning_fields)
  File "C:\Users\ytann\Desktop\python\lib\site-packages\django\db\models\sql\compiler.py",line 1397,in execute_sql
    cursor.execute(sql,params)
  File "C:\Users\ytann\Desktop\python\lib\site-packages\django\db\backends\utils.py",line 66,in execute
    return self._execute_with_wrappers(sql,params,many=False,executor=self._execute)
  File "C:\Users\ytann\Desktop\python\lib\site-packages\django\db\backends\utils.py",line 75,in _execute_with_wrappers
    return executor(sql,many,context)
  File "C:\Users\ytann\Desktop\python\lib\site-packages\django\db\backends\utils.py",line 84,in _execute
    return self.cursor.execute(sql,params)
  File "C:\Users\ytann\Desktop\python\lib\site-packages\django\db\utils.py",line 90,in __exit__
    raise dj_exc_value.with_traceback(traceback) from exc_value
  File "C:\Users\ytann\Desktop\python\lib\site-packages\django\db\backends\utils.py",params)
  File "C:\Users\ytann\Desktop\python\lib\site-packages\django\db\backends\sqlite3\base.py",line 413,in execute
    return Database.Cursor.execute(self,query,params)
django.db.utils.IntegrityError: NOT NULL constraint failed: User_wishlist.ISBN_id

**编辑** 我觉得执行self.client.post有点问题，但我似乎无法弄清楚问题所在

解决方法

在test.py中使用此：

response1 = self.client.post(reverse('TextSearch:wishlist',kwargs={'isbn': '976354890'}))

代替：

response1 = self.client.post(reverse('TextSearch:wishlist',args=("976354890",)))