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pythondjangodjango-signalsformset

how reconnect django signals after disconnected from a for loop formset


i want send signals only for one view in a formset , i disconnected the signal after the first loop , now i want to reconnect the signal for a new view

views.py

def ProductOrderCreate(request):

if request.method=='GET':
    formset = ProductFormSet(request.GET or None)

elif request.method=='POST':
    formset = ProductFormSet(request.POST)
    if formset.is_valid():
        for form in formset:

            product = form.cleaned_data.get('product')
            quantity = form.cleaned_data.get('quantity')

            ProductOrder(product=product , 
                            quantity=quantity).save()         
    signals.pre_save.disconnect(create_order_instance,sender=ProductOrder)

        return redirect('/orders/')


return render(request , 'create_product_order.html' , 
    {'forms':formset}) 

signals

@receiver(pre_save , sender=ProductOrder)
def create_order_instance(sender, instance, **kwargs):
    Order.objects.create()

pre_save.connect(create_order_instance,sender=ProductOrder)

@receiver(pre_save,sender=ProductOrder)
def create_ordering(sender,instance,**kwargs):
if not instance.ordering:
    instance.ordering = Order.objects.order_by('-pk')[0]
pre_save.connect(create_ordering,sender=ProductOrder)

models.py

class Product(models.Model):
name = models.CharField(max_length=50)
price = models.PositiveIntegerField(default=1)

def __str__(self):
    return self.name


class Order(models.Model):
id = models.AutoField(primary_key = True)
products = models.ManyToManyField(Product ,through='ProductOrder') 


@property
def total(self):
    return self.productorder_set.aggregate(
        price_sum=Sum(F('quantity') * F('product__price'), 
output_field=IntegerField()) )['price_sum'] 



class ProductOrder(models.Model):


product = models.ForeignKey(Product, on_delete=models.CASCADE,default='' )
ordering = models.ForeignKey(Order, 
on_delete=models.CASCADE,blank=True,null=True)
quantity = models.IntegerField(default=1)

forms.py

class ProductOrdering(forms.ModelForm):
class Meta:
    model = ProductOrder
    fields = ['product','ordering','quantity']

ProductFormSet  = formset_factory(ProductOrdering , extra=2)

now , i want to reconnect the signals for the next view

where should i put this code

signals.pre_save.connect(create_order_instance,sender=ProductOrder)

i put connected code after the render() but doesnt work as i expected , also outside of the function still not reconnected


Solution

  • Put the logic in the view

        ordering = Order.objects.create()
    
        for form in formset:
    
            product = form.cleaned_data.get('product')
            quantity = form.cleaned_data.get('quantity')
    
            ProductOrder(
                product=product, 
                quantity=quantity,
                ordering=ordering
            ).save()