CODEWITHSUNDEEP
pythondjangoformsdjango-crispy-forms
phicon
phicon

Reputation: 3617

Django - Disable form select field validation

I have a form that lets me first select a product type and then select the product. As i have 1000+ products i use the following to filter the product list to improve performance.

I have the following inlineform in my views.py

OrderLineFormSet = inlineformset_factory(OrderHeader, OrderLine, OrderLineForm, extra = 1)

In my forms.py i check if there is already a product selected. If there is a product selected i only show the products with the same product type to improve load performance. If a product is empty it will load all product options so it will let me save the form after selection.

class OrderLineForm(forms.ModelForm):

def __init__(self, *args, **kwargs):
    super(OrderLineForm, self).__init__(*args, **kwargs)
    self.helper = FormHelper(self)
    self.helper.form_show_errors = True
    self.helper.error_text_inline = False
    if self.instance.product is not None:        
        self.fields['product'] = forms.ModelChoiceField(queryset=Product.objects.filter(product_type_id=self.instance.product_type_id), required=False)

This results in the following form

enter image description here

However, when i change the Product type on an existing form (and then use jQuery to update the Product dropdown) i get an error saving. I know this is because the selection is not an option in the dropdown.

enter image description here

My question: How can i disable this error so it saves the option i selected, regardless of the original options.

Below you will find my views.py for this form

def orderline_formset(request, id=None):

OrderLineFormSet = inlineformset_factory(OrderHeader, OrderLine, OrderLineForm, extra = 1)

orderheader = None
orderid = None
orderheaderid = 0

if id:
    orderid = OrderHeader.objects.get(pk=id)

if request.POST:
    if orderid:
        form = OrderHeaderForm(request.POST, instance=orderid)
        formset = OrderLineFormSet(request.POST,instance=orderid)
    else:
        form = OrderHeaderForm(request.POST)
        formset = OrderLineFormSet(request.POST)

    if form.is_valid() and formset.is_valid():
        if orderid:
            form.save()  # update object
        else:
            orderid = form.save()  # create object
        formset.instance = orderid
        formset.save()
        messages.success(request, 'Order saved succesfully!')
        return HttpResponseRedirect('/orderline_formset/' + str(orderid.pk))

    else:  # form invalid
        messages.error(request, 'Order save error, please check mandatory fields')


else:  # request.GET
    if orderid:
        invoiceheader = "" 
        if orderid.orderheader_invoice:
            invoiceheader = " -- Invoice " + str(orderid.orderheader_invoice) 
        orderheader = "Order " + str(orderid.pk) + invoiceheader

        orderheaderid = orderid.pk
        form = OrderHeaderForm(instance=orderid)
        formset = OrderLineFormSet(instance=orderid)
    else:
        orderheader = "New Order"
        orderheaderid = 0
        form = OrderHeaderForm(instance=OrderHeader())
        formset = OrderLineFormSet(instance=OrderHeader())

return render_to_response("order-add.html", {'form' : form,'formset': formset, 
                            'orderheader': orderheader,
                            'orderheaderid': orderheaderid},
                            context_instance=RequestContext(request))

Upvotes: 16

Views: 16724

Answers (4)

Matthew
Matthew

Reputation: 635

Updating @ruddra 's answer for Django 1.11:

    class DynamicModelChoiceField(ModelChoiceField):
    def to_python(self, value):
        try:
            value = super().to_python(value)
        except ValidationError:
            key = self.to_field_name or 'pk'
            value = self.queryset.model.objects.filter(**{key: value})
            if not value.exists():
                raise
            value = value.first()
        return value

Upvotes: 2

ruddra
ruddra

Reputation: 51998

Override ModelChoiceField, for example:

class MyModelChoiceField(ModelChoiceField):

   def to_python(self, value):
        try:
            value = super(MyModelChoiceField, self).to_python(value)
        except self.queryset.model.DoesNotExist:
            key = self.to_field_name or 'pk'
            value = Product.objects.filter(**{key: value})
            if not value.exists():
               raise ValidationError(self.error_messages['invalid_choice'], code='invalid_choice')
            else:
               value= value.first()
       return value

And use it in your form.

self.fields['product'] = MyModelChoiceField(queryset=Product.objects.filter(product_type_id=self.instance.product_type_id), required=False)

Upvotes: 11

VelikiiNehochuha
VelikiiNehochuha

Reputation: 4373

class OrderLineForm(forms.ModelForm):

    def __init__(self, *args, **kwargs):
        super(OrderLineForm, self).__init__(*args, **kwargs)
        self.helper = FormHelper(self)
        self.helper.form_show_errors = True
        self.helper.error_text_inline = False
        self.fields['product'] = forms.ModelChoiceField(
            queryset=Product.objects.all())
        self.fields['product'].required = False

After this you can filter select with jquery filters.

Upvotes: 0

Ramast
Ramast

Reputation: 7719

You must change

    self.fields['product'] = forms.ModelChoiceField(queryset=Product.objects.filter(product_type_id=self.instance.product_type_id), required=False)

To

    self.fields['product'] = forms.ModelChoiceField(queryset=Product.objects.all(), required=False)

But you already know that and don't want it for performance reasons so your other solution is changing it to 

self.fields['product'] = ModelChoiceField(queryset=Product.objects.all(),  widget=forms.HiddenInput, required=False)

then inside your template you manually construct your <select> tag and using JS handle onchange event and make it update the product field

Upvotes: 1

Related Questions