如何从长轮询中获取响应数据？

Posted 2023-05-08

【中文标题】如何从长轮询中获取响应数据？

【英文标题】：How to get response data from long polling?

【发布时间】：2019-09-17 12:58:39

【问题描述】：

我在Django (1.11) 中做了一个long polling。但我不明白为什么JsonResponse 返回未定义的值？

ajax

$('.txt_link > a').on('click', function() 
  $.ajax(
    type: 'GET',
    url: '',
    success: function(data)
      console.log(data.title)              //undefined
    
  )
)

查看

class ProviderCreateView(CreateView):
    form_class = ProviderForm
    template_name = 'provider_create.html'

    def form_valid(self, form):
        ...

    def get_context_data(self, **kwargs):
        ctx = super(ProviderCreateView, self).get_context_data(**kwargs)
        ctx['organizations'] = Organization.objects.filter(user=self.request.user)
        last_organization = Organization.objects.filter(user=self.request.user).first()

        if self.request.is_ajax():
            while True:
                curr_organization = Organization.objects.filter(user=self.request.user).first()
                if last_organization != curr_organization:
                    template_ajax = render_to_string(
                        template_name='provider_create.html',
                        context=ctx
                    )
                    return JsonResponse(
                        'success': True,
                        'template': template_ajax,
                        'pk': curr_organization.pk,
                        'title': curr_organization.title
                        )

                time.sleep(2)
        return ctx

【参考方案1】：

您的代码没有意义。您应该从您的 CreateView 创建一个单独的视图，然后将您的 GET 请求路由到那里。

例子：

class OrganizationView(View):
    def get(self, request, *args, **kwargs):
         curr_organization = Organization.objects.filter(user=request.user).first()

         if last_organization != curr_organization:  # What is `last_organization`? Calculate it above and this condition will work.
             data = 
                 'success': True,
                 'curr_organization_pk': curr_organization.pk,
                 'curr_organization_title': curr_organization.title
             
         else:
             data = 'success': False
         return JsonResponse(data)

【讨论】：

非常感谢。我认为这一切都可以在一个视图中完成。