class Join(models.Model):
    email =  models.EmailField(unique = True)
    ref_id = models.CharField(max_length=120, default='ABC', unique=True)
    ip_address =  models.CharField(max_length = 120, default = 'ABC')
    timestamp = models.DateTimeField(auto_now_add = True, auto_now = False)
    updated = models.DateTimeField(auto_now_add = False, auto_now = True)
    def __unicode__(self):
        return "%s %s" %(self.email, self.ref_id)

    class Meta:
        unique_together = ("email", "ref_id",)

import uuid
def get_ref_id():
    ref_id = str(uuid.uuid4())[:11].replace('-','').lower()
    try:
        id_exists = Join.objects.get(ref_id=ref_id)
        get_ref_id()
    except:
        return ref_id

def home(request):
    form = JoinForm(request.POST or None)
    if form.is_valid():
        new_join = form.save(commit = False)
        email = form.cleaned_data['email']
        new_join_old, created = Join.objects.get_or_create(email = email)
        if created:
            new_join_old.ref_id = get_ref_id()
            new_join_old.ip_address = get_ip(request)
            new_join_old.save()     
    context = {"form":form}
    template = "home.html"
    return render(request, template, context)