A Django middleware that process JSON data into the appropriate GET or POST variable. I use this with AngularJS, by default POST requests are sent as JSON instead of the urlencoded data expected by Django.

middleware.py

class JSONMiddleware(object):
    """
    Process application/json requests data from GET and POST requests.
    """
    def process_request(self, request):
        if 'application/json' in request.META['CONTENT_TYPE']:
            # load the json data
            data = json.loads(request.body)
            # for consistency sake, we want to return
            # a Django QueryDict and not a plain Dict.
            # The primary difference is that the QueryDict stores
            # every value in a list and is, by default, immutable.
            # The primary issue is making sure that list values are
            # properly inserted into the QueryDict.  If we simply
            # do a q_data.update(data), any list values will be wrapped
            # in another list. By iterating through the list and updating
            # for each value, we get the expected result of a single list.
            q_data = QueryDict('', mutable=True)
            for key, value in data.iteritems():
                if isinstance(value, list):
                    # need to iterate through the list and upate
                    # so that the list does not get wrapped in an
                    # additional list.
                    for x in value:
                        q_data.update({key: x})
                else:
                    q_data.update({key: value})

            if request.method == 'GET':
                request.GET = q_data

            if request.method == 'POST':
                request.POST = q_data

        return None

There is a KeyError exception in case there is no content_type key/value pair in request. I'd recommend you just to put try except block to catch this error and return None as well

Thank you for the gist i was previously using a transform request in my angular scripts but this is better
Yes like dusan87 mentioned django throws an error in case no 'CONTENT_TYPE' key is present in the request.
You can use a try and except as suggested or just add request.META.get('CONTENT_TYPE') to the if condition.
For example a statement like,

if request.META.get('CONTENT_TYPE') and 'application/json' in request.META.get('CONTENT_TYPE'):
...

For completeness' sake, import json and QueryDict

from django.http import HttpResponse, QueryDict

import json


class JSONMiddleware:
    """
    Process application/json requests data from GET and POST requests.
    """

    def __init__(self, get_response):
        self.get_response = get_response

    def __call__(self, request):
        if request.META.get('CONTENT_TYPE') and 'application/json' in request.META.get('CONTENT_TYPE'):
            try:
                data = json.loads(request.body)

                q_data = QueryDict('', mutable=True)
                for key, value in data.items():
                    if isinstance(value, list):
                        for x in value:
                            q_data.update({key: x})
                    else:
                        q_data.update({key: value})

                if request.method == 'GET':
                    request.GET = q_data

                if request.method == 'POST':
                    request.POST = q_data

                return self.get_response(request)
            except json.JSONDecodeError:
                return HttpResponse("JSON Decode Error", status=400)

        return self.get_response(request)

Updated to Django 2.2 and Python 3 and applied all comments suggestions. Also return a "Bad Request" in case of JSON parsing problem.