[Answered ]-How do I send JSON data to Django app via Python urllib?

What’s your urlconf look like? If it looks like '^web_app/$' and APPEND_SLASH=True in settings, which is default, you need to use "http://127.0.0.1:8000/web_app/" (note the suffix slash). Or else Django would try to redirect /web_app to /web_app/ if there is no matching, then complains about redirecting a POST request.

Also, its meaningless to set 'Content-Type':'application/json' for HTTP request, you could set this and break the requirement of urllib2 by passing it a JSON-dumped string; but then you should parse request.body by yourself instead of using request.POST. application/json is normally for specifying the Content-Type of response.