How to retrieve user selections from a previous form - django

Question

I have several forms that take people through steps and below are the first two and the simplest ones and makes it easy to explain what i am having problem with.
The following two views are login required and contain one form on each. First view is the new_operator where the user fills out a single text input field. Second view is the new_asset where the user fills one text input field as the asset name and selects an operator from the a select/dropdown field. The question is how can i get the form to remember the operator name the user created in the previous form and make it as the default option? To be clear, i still want the user to select any other operator if they choose to do so but i want the option they just created to be the default. Thanks a lot in advance for the help.
First, here are the models:
class OperatorCompany(models.Model):
name = models.CharField(max_length=50, unique=True)
created_at = models.DateTimeField(default=timezone.now)
created_by = models.ForeignKey(User, related_name='operator_added_by', null=True, on_delete=models.SET_NULL)
class Meta:
verbose_name = "Operator Company"
verbose_name_plural = "Operator Companies"
def __str__(self):
return self.name
class AssetName(models.Model):
name = models.CharField(max_length=50, unique=True)
operator = models.ForeignKey(OperatorCompany, related_name='asset', on_delete=models.CASCADE)
created_at = models.DateTimeField(default=timezone.now)
created_by = models.ForeignKey(User, related_name='asset_added_by', null=True,
on_delete=models.SET_NULL)
class Meta:
verbose_name = "Asset"
verbose_name_plural = "Assets"
def __str__(self):
return self.name
views.py
def new_operator(request):
if request.method == 'POST':
form = NewOperatorForm(request.POST)
if form.is_valid():
newoperator = form.save(commit=False)
newoperator.created_by = request.user
newoperator.created_at = timezone.now()
newoperator.save()
return redirect('wellsurfer:new_asset')
else:
form = NewOperatorForm()
return render(request, 'wellsurfer/create_new_operator.html', {'create_operator': form})
def new_asset(request):
if request.method == 'POST':
form = NewAssetForm(request.POST)
if form.is_valid():
newasset = form.save(commit=False)
newasset.created_by = request.user
newasset.created_at = timezone.now()
newasset.save()
return redirect('wellsurfer:new_pad')
else:
form = NewAssetForm()
return render(request, 'wellsurfer/create_new_asset.html', {'create_asset': form})
and following are the forms.py without the init, clean functions and the widgets
class NewOperatorForm(forms.ModelForm):
class Meta:
model = OperatorCompany
fields = ('name',)
class NewAssetForm(forms.ModelForm):
class Meta:
model = AssetName
fields = ('name', 'operator')

Answer 1

To share data between multiple pages, you can use session variables. These are stored on the server and associated to clients according to the session cookie they communicate to the server at every request.
Typically, in the first view, you would add after save():
request.session['latest_created_operator_id'] = newoperator.id
to save in the session the operator id.
And in the second view, after the else,
operator_id = request.session.get('latest_created_operator_id', None)
operator = Operator.objects.filter(id=operator_id).first() # returns None if not found
form = NewAssetForm(initial={'operator': operator})
retrieves the operator and populates the form.
(That's untested code; you may need to edit a bit.)

Answer 2

At a glance, maybe something like this would work.
What you can do is add another URL in urls.py for new_asset which accepts a OperatorCompany id. I don't have your url config but it could be something like:
urls.py
path('wellsurfer/new_asset/<int:operator_id>', new_asset, name='wellsurfer:new_asset_operator')
view.py
def new_operator(request):
if request.method == 'POST':
form = NewOperatorForm(request.POST)
if form.is_valid():
newoperator = form.save(commit=False)
newoperator.created_by = request.user
newoperator.created_at = timezone.now()
newoperator.save()
return redirect('wellsurfer:new_asset', operator_id=newoperator.id)
else:
form = NewOperatorForm()
return render(request, 'wellsurfer/create_new_operator.html', {'create_operator': form})
def new_asset(request, operator_id=None):
if request.method == 'POST':
form = NewAssetForm(request.POST)
if form.is_valid():
newasset = form.save(commit=False)
newasset.created_by = request.user
newasset.created_at = timezone.now()
newasset.save()
return redirect('wellsurfer:new_pad')
else:
form = NewAssetForm()
if operator_id is not None:
operator_company = OperatorCompany.objects.get(pk=operator_id)
form.fields['operator'].initial = operator_company
return render(request, 'wellsurfer/create_new_asset.html', {'create_asset': form})