karmaworld/utils/ajax_increment.py

   1 import json
   2 from django.core.exceptions import ObjectDoesNotExist
   3 from django.http import HttpResponseBadRequest, HttpResponseNotFound, HttpResponse
   4
   5
   6 def format_session_increment_field(cls, id, field):
   7     return cls.__name__ + '-' + field + '-' + str(id)
   8
   9
  10 def ajax_base(cls, request, pk, event_processor):
  11     """Handle an AJAX request"""
  12     if not (request.method == 'POST' and request.is_ajax()):
  13         # return that the api call failed
  14         return HttpResponseBadRequest(json.dumps({'status': 'fail', 'message': 'must be a POST ajax request'}),
  15                                       mimetype="application/json")
  16
  17     try:
  18         obj = cls.objects.get(pk=pk)
  19         event_processor(request.user, obj)
  20
  21     except ObjectDoesNotExist:
  22         return HttpResponseNotFound(json.dumps({'status': 'fail', 'message': 'id does not match a ' + cls.__name__}),
  23                                     mimetype="application/json")
  24
  25     return HttpResponse(status=204)
  26
  27
  28 def ajax_increment(cls, request, pk, field, event_processor=None):
  29     def ajax_increment_work(request_user, obj):
  30         count = getattr(obj, field)
  31         setattr(obj, field,  count+1)
  32         obj.save()
  33
  34         if event_processor:
  35             event_processor(request.user, obj)
  36
  37         # Record that user has performed this, to prevent
  38         # them from doing it again
  39         request.session[format_session_increment_field(cls, pk, field)] = True
  40
  41     return ajax_base(cls, request, pk, ajax_increment_work)