Question

I don’t understand why code like this give “has_children” attribute to every item object:

items = Items.objects.filter(user=request.user).filter(parent=None)
for i in items:
    if i.get_children():
        i.has_children = True
    else:
        i.has_children = False
return render_to_response('items_base.html', {'items': items}, context_instance=RequestContext(request))

But code like this, don’t do the trick, even if it don’t raise any errors:

response = HttpResponse()
response['ContentType'] = "text/javascript"
try:
    items = Items.objects.get(id=id).get_children()    
    for i in items:
        if i.get_children():
            i.has_children = True
        else:
            i.has_children = False                
    response.write(serializers.serialize("json", items))
    return response
except ObjectDoesNotExist:
    return HttpResponse(u"There is no page like this")

Has someone has any suggestions of what is wrong with secuond code?

Answer 1

Django serialization is excluding any attributes which were not actually defined as model fields.

You have some options:

• Convert the Item objects into dictionaries of {fieldname: value} and use the json library to serialize them (or create a custom JSONEncoder).
• Use this ‘Full Serializer’ code to serialize your extra fields.