我为什么在Django中遇到这个错误（我尝试做304未修改）

Question

def list_ajax(reqest):
    #q = request.GET.get('q',None)
    #get all where var = q.
    return ...
list_ajax = condition(etag_func=list_ajax)(list_ajax)

如你所见，我想在结果相同的情况下返回一个304给客户端。但是，我遇到了这个Django错误，为什么会这样呢？

Traceback:
File "/usr/local/lib/python2.6/dist-packages/django/core/handlers/base.py" in get_response
  92.                 response = callback(request, *callback_args, **callback_kwargs)
File "/usr/local/lib/python2.6/dist-packages/django/views/decorators/http.py" in inner
  130.                 response['ETag'] = quote_etag(res_etag)
File "/usr/local/lib/python2.6/dist-packages/django/utils/http.py" in quote_etag
  118.     return '"%s"' % etag.replace('\\', '\\\\').replace('"', '\\"')

Exception Type: AttributeError at /list/ajax/
Exception Value: 'HttpResponse' object has no attribute 'replace'

补充说明：我做了这个：

def etag_generate(p):
    thestring =  cPickle.dumps(p)
    return thestring

@etag(etag_generate)
def list_ajax(request):
    ...
    etag_generate(mydictresults)
    return render_to_response("list.html",mydictresults)

我把所有的结果都变成了字符串，希望能从这个字典生成一个哈希值。但是，似乎@etag不让我生成cPickle。错误是：

Exception Type: TypeError at /list/ajax/ 
Exception Value: can't pickle file objects

Answer 1

正确的 etag_func 应该返回一些可以被序列化的数据。对于你的情况，最好的选择是像这样的内容：

@etag(_get_list)
def list_ajax(request):
    objects = _get_list(request)
    return render_to_response("list.html", {"objects": objects})

def _get_list(request):
    q = request.GET["q"]
    # find and return records here
    # ...

Answer 2

解决了。

请求已经提交。

def list_ajax_etag(request):
    return str(request.GET.get('l',''))+str(request.GET.get('a',''))