我无法理解，为什么只有 delete_node 不起作用

Question

以下是来自用户的三个请求，create_node、rename_node 工作正常但 delete_node 请求无效。

requests:
[31/Aug/2018 17:00:53] "GET /buildknowledge/?operation=create_node&id=1&text=New+node HTTP/1.1" 200 16071
[31/Aug/2018 17:01:10] "GET /buildknowledge/?operation=rename_node&id=63&text=pkkkk HTTP/1.1" 200 16071
[31/Aug/2018 17:02:33] "GET /buildknowledge/?operation=delete_node&id=63 HTTP/1.1" 200 16071

views.py:

def basetest(request):
     cu_id = request.user.id
     if 'operation' in request.GET and "id" in request.GET and "text" in request.GET:
       operation = request.GET['operation']
       pid=request.GET['id']
       nodename=request.GET['text']
       if "create_node" == operation:
          p=Buildkb4.objects.create    (parent=pid,created_by=cu_id,text=nodename)
          p.save()
       elif "delete_node" == operation:
           Buildkb4.objects.filter(pk=pid).delete()
       elif "rename_node" == operation:
           Buildkb4.objects.filter(pk=pid).update(text=nodename)
   return render(request,"registration/basetest.html")

Answer 1

Note: It is not a good idea to use GET requests to perform side-effects (like updating or removing records in a database). Therefore I would advice to change such requests to a POST, DELETE or PATCH. More information at the bottom of this post.

根据您显示的日志，删除调用在 querystring 中带有两个参数：operation 和 id。但是第一个 if 语句还需要一个 text 参数：

def basetest(request):
     cu_id = request.user.id
     <b>if 'operation' in request.GET and "id" in request.GET and "text" in request.GET:</b>
       operation = request.GET['operation']
       pid=request.GET['id']
       nodename=request.GET['text']
       if "create_node" == operation:
          p=Buildkb4.objects.create    (parent=pid,created_by=cu_id,text=nodename)
          p.save()
       elif "delete_node" == operation:
           Buildkb4.objects.filter(pk=pid).delete()
       elif "rename_node" == operation:
           Buildkb4.objects.filter(pk=pid).update(text=nodename)
   return render(request,"registration/basetest.html")

所以这永远不会达到 elif "delete_node" == operation: 的情况。

您可以通过减少检查限制来解决此问题，例如：

def basetest(request):
     cu_id = request.user.id
     if 'operation' in request.GET and "id" in request.GET:
       operation = request.GET['operation']
       pid=request.GET['id']
       if "delete_node" == operation:
           Buildkb4.objects.filter(pk=pid).delete()
       elif 'text' in request.GET:
           nodename=request.GET['text']
           if "create_node" == operation:
               p=Buildkb4.objects.create(parent=pid,created_by=cu_id,text=nodename)
           elif "rename_node" == operation:
               Buildkb4.objects.filter(pk=pid).update(text=nodename)
   return render(request,"registration/basetest.html")

现在可以使用了。但是 GET 应该没有副作用。所以你基本上违反了 GET 请求的约定。

通常通过 POST 或 DELETE 请求执行删除，而非 GET 请求。更改数据也由 POST 或 PATCH 请求处理，同样是 而不是 GET 请求。通过发出带有副作用的 GET 请求，机器人（如搜索引擎）可能会查询 URL，并删除 and/or 更新您的数据。这可能不是你想要的。

我无法理解，为什么只有 delete_node 不起作用

i am unable to understand ,why only delete_node not working

python

django

jstree