Save and retrieve a form with session? - django

Question

I have a context_processor.py file with the following function
def include_user_create(request):
if 'form' not in request.session:
form = CreateUserForm()
else:
form = request.session['form']
return { 'create_user_form' : form }
I use this to display my register in my base.html template, so that I may reuse it for all pages. A function create_user handles the form submit
def create_user(request):
form = CreateUserForm(request.POST or None, request.FILES or None)
if request.method == 'POST':
if form.is_valid():
user = form.save(commit=False)
user.save()
user = authenticate(username=user.email, password=user.password)
else:
request.session['form'] = form #<--- save
next = request.POST.get('next', '/')
return HttpResponseRedirect(next)
If the form is invalid I'd like to save the form so that the context_processor may reuse the form, for the purpose of saving the errors so they may be displayed in the template.
Doing this gives me a error:
TypeError: <CreateUserForm bound=True, valid=False, fields=(email;password;confirm_password)> is not JSON serializable
Is it possible to get this to work somehow?

Answer 1

You have this error because a form object is not JSON serializable, and the default session serializer is serializers.JSONSerializer.
Try to change it to a pickle serializer in your settings.py:
SESSION_SERIALIZER = 'django.contrib.sessions.serializers.PickleSerializer'
EDIT:
With this setting, you don't have to care about pickle serialization, you just have to write:
request.session['form'] = form