how to overide in forms queryset none() attribute and somehow allow to save the field? - django

Question

I have models.py
class Visit(Model):
reference_visit = models.ForeignKey('self',
help_text="Visit needs a refrence to Prior Visits",
null=True, blank=True)
show_prior_responses = models.BooleanField(default=False,
help_text="Show PriorResponses")
# has many field but i am making it short.
def __unicode__(self):
result = """Visit id:%s pt:%s""" % (self.id, self.patient.id)
return result
forms.py
class VisitSetupForm(Form):
list_visit_ids = ModelChoiceField(
queryset=Visit.objects.none(),
empty_label='Select Revisit ID',required=False)
show_prior_visit = ModelChoiceField(
queryset=User.objects.all(),
empty_label="Select User for Revisit",required = False)
has many but question is on list_visit_ids.
views.py
def setup(request):
"""
Allow an Admin user the ability to setup a patient & visit all at once.
"""
if request.user.is_superuser:
form_class = AdminVisitSetupForm
all_topics = True
else:
form_class = VisitSetupForm
all_topics = False
f = form_class()
# Get a list of topics for each report.
report_topics = {}
for r in Interview.objects.all():
report_topics[r.id] = [t['ad'] for t in r.topics.values('ad')]
data = {
'superuser':request.user.is_superuser,
'report_topics':simplejson.dumps(report_topics)
}
try:
request.user.reviewer
data['reviewer'] = True
except:
pass
if request.method == "POST":
f = form_class(request.POST)
if f.is_valid():
# Create the patient, generate a password, and send them on their way.
cd = f.cleaned_data
patient = None
if cd['revisit']:
# Check for an existing user first.
try:
patient = Patient.objects.get(username=cd['username'])
except Patient.DoesNotExist, e:
data['form'] = f
data['msg'] = 'There is no user with this username.'
return render_to_response('visit/setup.html', data, context_instance=RequestContext(request))
admin_user = get_user(request)
organization = None
if admin_user:
organization = admin_user.organization
if patient and not request.user.is_superuser:
# Make sure the patient they've selected is one of their own.
if patient.organization != organization:
return HttpResponseForbidden('You are not allowed to see this page.')
if not patient:
password = generate_password()
user = User.objects.create_user(cd['username'], cd['contact_email'], password)
user.first_name = cd['first_name']
user.last_name = cd['last_name']
user.save()
patient = Patient(
user=user,
username=user.username,
contact_phone=cd['contact_phone'],
date_of_birth=cd['date_of_birth'],
email=user.email,
first_name=user.first_name,
gender=cd['gender'],
last_name=user.last_name,
maiden_name=cd['maiden_name'],
organization=organization,
patient_type=cd['patient_type'],
security_answer=cd['security_answer'],
security_question=cd['security_question'],
)
patient.save()
# Send them an email.
t = loader.get_template('www/new_account.txt')
c = Context({
'password':'%s-%s-%s' % (password[:3], password[3:5], password[5:]),
'patient':patient
})
msg = t.render(c)
try:
send_mail(
'A request by your physician to do an online medical history before your appointment.',
msg,
'support#careprep.com',
[user.email]
)
except Exception, e:
log.error('Could not send email for new account %s because: [%s]' % (user.username, e))
request.session['password'] = password
# Create the Visit, too.
interview = cd['interview']
list_visit_ids = cd['list_visit_ids']
print list_visit_ids
visit = Visit(
reference_visit = cd['list_visit_ids'],
show_prior_responses = cd['show_prior_responses'],
patient=patient
)
if request.user.is_superuser:
topics = cd['topics']
else:
topics = set(list(interview.topics.all()) + list(cd['topics']))
reviewer_mode = cd.get('reviewer_mode') or patient.patient_type == 'Reviewer'
url, visit = initialize_visit(
request,
patient=patient,
starting_section=interview.starting_section,
visit_title='%s %s' % (patient, interview.title),
topics=topics,
reviewer_mode=reviewer_mode,
chief_complaint=cd['chief_complaint'],
location=cd['interview_site'],
reference_visit = cd['list_visit_ids'],
show_prior_responses = cd['show_prior_responses'],
)
next_url = "/visit/confirmation/%s/%s/?next=%s" % (patient.user.id, interview.id, url)
else:
v = Visit.objects.get(pk=request.POST['list_visit_ids'])
print v
return HttpResponseRedirect(next_url)
# all the fields that are not given pls ignore.
The template is fine.
Now watch forms.py when i do list_visit_ids = ModelChoiceField(queryset=Visit.objects.all(), empty_label='Select Revisit ID',required=False) It works perfectly fine on my local machine.But on my server it has around 6000 visit objects so this page hangs or i should say keep on loading.
So initially i changed it to list_visit_ids = ModelChoiceField(queryset=Visit.objects.none(), empty_label='Select Revisit ID',required=False)
Now i know that by this the form becomes invalid and should go to the else part Now my question how do i make reference_visit=cd['list_visit_ids'] in else (form is invalid)
case save().How do i override the none() attribute.
Thanks in advance i will really appreciate.

Answer 1

If your goal is to save your html page load by removing the 6000 choices (which I've done too: 10000+ <option> fields wrapped by misc html will absolutely choke a page), you shouldn't be using a ChoiceField at all. By setting queryset=Visit.objects.none() you're allowing zero choices and nothing passed in will validate.
You either show 6000 select item drop downs, radio boxes, etc., or find a way to /not/ have a giant select drop down (such as a hidden input or charfield), not fake around a ModelChoiceField who's main purpose is to populate that select drop down and validate.
In short: don't use a ModelChoiceField if you're not going to be using the html choices generated by it. Use something else and do the validation / model pulling yourself via the clean_FOO methods.
class MyForm(forms.Form):
my_input = forms.CharField()
def clean_my_input(self):
input = self.cleaned_data.get('my_input')
try:
return MyModel.objects.get(pk=input) # add a filter here if you want
# (whatever filters you were using in the queryset argument)
except MyModel.DoesNotExist:
raise forms.ValidationError("Doesn't exist / is invalid")
return input