Django form efficiency issue - django

Question

I have inherited some code that was handled by multiple developers, and as such, there is no standard for the product. I am having significant performance issues, and am remedying a lot of them, but don't know how to break this one down. When the user submits on a page that pre-populates with data, and allows the user to select a date for the activity, they can submit, and anything with a date goes away for them. The problem is within the views.py. When the user submits, the following code runs, and hangs up at formset = formset(request.POST). I'm assuming that there are multiple db calls happening, but am not seeing them when I print to terminal. Below is the entirety of the submission process.
STATES = ['Routed','Reconciled']
formset = None
form = StudyOnlyForm()
study_pk = request.GET.get('study', '0')
if study_pk == '' or study_pk == '0':
study_pk = 0
# child transactions that are 'Recoginzed',
# reportable with a 'Routed' parent
qs = Transaction.objects.filter(contract__reportable=True,
cleared = False,
contract__study__pk=study_pk,
transaction_status='Recognized',
parent_transaction__isnull=False,
parent_transaction__transaction_status__in=STATES)
#Designed to capture standalone contracts
qs1 = Transaction.objects.filter(contract__reportable=True,
cleared = False,
contract__study__pk=study_pk,
contract__contract_type__name='Standalone',
transaction_status__in=STATES)
#Captures Arms contracts for Milestone payments
parent_list = []
arms_list = []
parent = Transaction.objects.filter(parent_transaction__isnull=True,
contract__reportable=True,
cleared = False,
contract__study__pk=study_pk,
contract__contract_type__name='ARMs',
transaction_status__in=STATES)
children = Transaction.objects.filter(contract__reportable=True,
cleared = False,
contract__study__pk=study_pk,
transaction_status='Recognized',
contract__contract_type__name='ARMs',
parent_transaction__isnull=False,
parent_transaction__transaction_status__in=STATES)
for child_item in children:
parent_list.append(child_item.parent_transaction.pk)
arms_list.append(child_item.pk)
for parent_item in parent:
if parent_item.pk not in parent_list:
arms_list.append(parent_item.pk)
qs3 = Transaction.objects.filter(pk__in=arms_list)
qs4 = qs | qs1 | qs3
qs = qs4.order_by('-pk')
formset = modelformset_factory(Transaction, form=PaidDateForm, extra=0, can_delete=False)
if request.method == "POST":
print 'if request.POST'
print datetime.datetime.now()
formset = formset(request.POST)
print 'created formset'
print datetime.datetime.now()
if formset.is_valid():
print 'formset valid'
print datetime.datetime.now()
updated_transactions = formset.save(commit=False)
print 'updated transactions'
print datetime.datetime.now()
for trans in updated_transactions:
if trans.paid_amount is not None and trans.date_cleared is not None:
trans_to_change = Transaction.objects.get(pk=trans.pk)
trans_to_change.paid_amount = trans.paid_amount
trans_to_change.date_cleared = trans.date_cleared
trans_to_change.paid_currency = trans_to_change.entered_currency
trans_to_change.paid_amount_usd =
Decimal(str(trans_to_change.paid_amount * Decimal(str(trans_to_change.exchange_rate)).quantize(Decimal('0.01')))).quantize(Decimal('0.01'))
trans_to_change.edited_by = request.user
trans_to_change.cleared = True
trans_to_change.save()
if updated_transactions:
messages.add_message(request, messages.INFO, 'The transactions have been updated successfully.')
return HttpResponseRedirect(reverse('track:update_pdate'))
else:
messages.add_message(request, messages.INFO, 'No transactions have been updated.')
return render_to_response(
'track/paid_date_update.html',
{'formset':formset,
'form': form,
'study_pk':study_pk,
},
context_instance=template.RequestContext(request))
else:
formset = formset(queryset=qs)
return render_to_response(
'track/paid_date_update.html',
{'formset':formset,
'form': form,
'study_pk':study_pk,
},
context_instance=template.RequestContext(request))
Forms:
class StudyOnlyForm(forms.Form):
action = forms.CharField(widget=forms.HiddenInput())
#
# JBL - Q4.0 changed this form to pull all studies (previously
# only 'active' studies), which really means all studies
# that are not 'ccc' studies
#
study = forms.ModelChoiceField(required=False,
label='Protocol',
queryset=Study.objects.all().exclude(study_status='ccc'))
def __init__(self, *args, **kwargs):
self.req = True
if 'req' in kwargs:
self.req = kwargs.pop('req')
super(StudyOnlyForm, self).__init__(*args, **kwargs)
print 'StudyOnlyForm() init'
self.fields['study'].required = self.req
class PaidDateForm(forms.ModelForm):
formfield_callback = jquery_datefield
paid_amount = forms.DecimalField(label="Cleared
Amount",max_digits=14,decimal_places=2,required=False)
date_cleared = forms.DateField(label="Cleared Date",widget=JQueryDateWidget(),
input_formats=settings.DATE_INPUT_FORMATS, required=False)
class Meta:
model = Transaction
include = ('date_time_created')
def __init__(self, *args, **kwargs):
super(PaidDateForm, self).__init__(*args, **kwargs)
print 'PaidDateForm init'
for field in self.fields:
if field != 'date_cleared':
self.fields[field].widget = forms.HiddenInput()
self.fields['paid_amount'].widget.attrs['size'] = 12
self.initial['paid_amount'] = '%.2f' % (self.instance.usd_amount)

Answer 1

You restrict the queryset in the GET branch, but not the POST branch. That means that the POST branch creates a formset containing every transaction.

Answer 2

replace your for loop:
for trans in updated_transactions.exclude(paid_amount=None, date_cleared=None).all():
trans_to_change = Transaction.objects.get(pk=trans.pk)
trans_to_change.paid_amount = trans.paid_amount
trans_to_change.date_cleared = trans.date_cleared
trans_to_change.paid_currency = trans_to_change.entered_currency
trans_to_change.paid_amount_usd = Decimal(str(trans_to_change.paid_amount * Decimal(str(trans_to_change.exchange_rate)).quantize(Decimal('0.01')))).quantize(Decimal('0.01'))
trans_to_change.edited_by = request.user
trans_to_change.cleared = True
trans_to_change.save()