Where's my JSON data in my incoming Django request?

If you are posting JSON to Django, I think you want request.body (request.raw_post_data on Django < 1.4). This will give you the raw JSON data sent via the post. From there you can process it further.

Here is an example using JavaScript, jQuery, jquery-json and Django.

JavaScript:

var myEvent = {id: calEvent.id, start: calEvent.start, end: calEvent.end,
               allDay: calEvent.allDay };
$.ajax({
    url: '/event/save-json/',
    type: 'POST',
    contentType: 'application/json; charset=utf-8',
    data: $.toJSON(myEvent),
    dataType: 'text',
    success: function(result) {
        alert(result.Result);
    }
});

Django:

def save_events_json(request):
    if request.is_ajax():
        if request.method == 'POST':
            print 'Raw Data: "%s"' % request.body   
    return HttpResponse("OK")

Django < 1.4:

  def save_events_json(request):
    if request.is_ajax():
        if request.method == 'POST':
            print 'Raw Data: "%s"' % request.raw_post_data
    return HttpResponse("OK")

I had the same problem. I had been posting a complex JSON response, and I couldn't read my data using the request.POST dictionary.

My JSON POST data was:

//JavaScript code:
//Requires json2.js and jQuery.
var response = {data:[{"a":1, "b":2},{"a":2, "b":2}]}
json_response = JSON.stringify(response); // proper serialization method, read 
                                          // http://ejohn.org/blog/ecmascript-5-strict-mode-json-and-more/
$.post('url',json_response);

In this case you need to use method provided by aurealus. Read the request.body and deserialize it with the json stdlib.

#Django code:
import json
def save_data(request):
  if request.method == 'POST':
    json_data = json.loads(request.body) # request.raw_post_data w/ Django < 1.4
    try:
      data = json_data['data']
    except KeyError:
      HttpResponseServerError("Malformed data!")
    HttpResponse("Got json data")

Method 1

Client : Send as JSON

$.ajax({
    url: 'example.com/ajax/',
    type: 'POST',
    contentType: 'application/json; charset=utf-8',
    processData: false,
    data: JSON.stringify({'name':'John', 'age': 42}),
    ...
});

//Sent as a JSON object {'name':'John', 'age': 42}

Server :

data = json.loads(request.body) # {'name':'John', 'age': 42}

Method 2

Client : Send as x-www-form-urlencoded
(Note: contentType & processData have changed, JSON.stringify is not needed)

$.ajax({
    url: 'example.com/ajax/',
    type: 'POST',    
    data: {'name':'John', 'age': 42},
    contentType: 'application/x-www-form-urlencoded; charset=utf-8',  //Default
    processData: true,       
});

//Sent as a query string name=John&age=42

Server :

data = request.POST # will be <QueryDict: {u'name':u'John', u'age': 42}>

Changed in 1.5+ : https://docs.djangoproject.com/en/dev/releases/1.5/#non-form-data-in-http-requests

Non-form data in HTTP requests :
request.POST will no longer include data posted via HTTP requests with non form-specific content-types in the header. In prior versions, data posted with content-types other than multipart/form-data or application/x-www-form-urlencoded would still end up represented in the request.POST attribute. Developers wishing to access the raw POST data for these cases, should use the request.body attribute instead.

Probably related

  • https://groups.google.com/forum/#!msg/django-developers/s8OZ9yNh-8c/yWeY138TpFEJ
  • https://code.djangoproject.com/ticket/17942 . Fixed in 1.7
  • http://homakov.blogspot.in/2012/06/x-www-form-urlencoded-vs-json-pros-and.html

Its important to remember Python 3 has a different way to represent strings - they are byte arrays.

Using Django 1.9 and Python 2.7 and sending the JSON data in the main body (not a header) you would use something like:

mydata = json.loads(request.body)

But for Django 1.9 and Python 3.4 you would use:

mydata = json.loads(request.body.decode("utf-8"))

I just went through this learning curve making my first Py3 Django app!


request.raw_response is now deprecated. Use request.body instead to process non-conventional form data such as XML payloads, binary images, etc.

Django documentation on the issue.