索引错误：在Django中列出索引超出范围

I'm using Django 1.7 with Django Rest Framework. I've written an API that detects the login of a user as follows:

我正在使用Django 1.7和Django Rest Framework。我编写了一个用于检测用户登录的API,如下所示:

def login_check(request):
    user = request.user
    if user.is_anonymous():
        return HttpResponse(json.dumps({
            'success': False
        }))
    else:
        try:
            user_obj = UserProfile.objects.get(user__pk=user.id)
        except UserProfile.DoesNotExist:
            main_obj = User.objects.get(pk=user.id)
            user_obj = UserProfile(user=main_obj)
            user_obj.save()
        fb_uid = SocialAccount.objects.filter(user_id=user.id, provider='facebook')
        print fb_uid[0].uid
        user_obj.profile_photo_url = "http://graph.facebook.com/{}/picture?width=300&height=300".format(fb_uid[0].uid)
        user_obj.save()
        serialized = UserProfileSerializer(user_obj)
        return Response(serialized.data, status=status.HTTP_200_OK)

I face an error with this view which shows the following traceback

我在此视图中遇到错误,显示以下回溯

IndexError at /loginCheck/
list index out of range
Request Method: GET
Request URL:    http://localhost:8000/loginCheck/
Django Version: 1.7.4
Exception Type: IndexError
Exception Value:    
list index out of range
Exception Location: f:\App\venv\lib\site-packages\django\db\models\query.py in __getitem__, line 178
Python Executable:  f:\App\venv\Scripts\python.exe
Python Version: 2.7.6
Python Path:    
['f:\\App',
 'f:\\App\\venv\\lib\\site-packages\\psycopg2-2.6-py2.7-win32.egg',
 'C:\\WINDOWS\\SYSTEM32\\python27.zip',
 'f:\\App\\venv\\DLLs',
 'f:\\App\\venv\\lib',
 'f:\\App\\venv\\lib\\plat-win',
 'f:\\App\\venv\\lib\\lib-tk',
 'f:\\App\\venv\\Scripts',
 'c:\\Python27\\Lib',
 'c:\\Python27\\DLLs',
 'c:\\Python27\\Lib\\lib-tk',
 'f:\\App\\venv',
 'f:\\App\\venv\\lib\\site-packages']

I'm not entirely sure if this is an error in my code or Django's query.py. I'd appreciate help in figuring out the problem here

我不完全确定这是我的代码或Django的query.py中的错误。我很感激帮助解决这个问题

2 个解决方案

#1

Try to use the first() method instead of [0] indexing of queryset:

尝试使用first()方法而不是[0]索引查询集:

so_account = SocialAccount.objects.filter(user_id=user.id,
                                          provider='facebook').first()
if so_account:
    fb_uid = so_account.uid
    ...

#2

In the django documentation

在django文档中

Says that:

Entry.objects.order_by('headline')[0]
Entry.objects.order_by('headline')[0:1].get()

Note, however, that the first of these will raise IndexError while the second will raise DoesNotExist if no objects match the given criteria. See get() for more details.

但请注意,如果没有对象符合给定条件,则第一个将引发IndexError,而第二个将引发DoesNotExist。有关详细信息,请参阅get()。

So if that is possible that your query will return no data at all. You might want to use Entry.objects.order_by('headline')[0:1].get() instead of its shortcut [0]

因此,如果可能您的查询将根本不返回任何数据。你可能想使用Entry.objects.order_by('headline')[0:1] .get()而不是它的快捷方式[0]

#1