I'm failing to update multiple data in my modelset at once - django-forms

Question

I have pre-populated my table with products data which I then retrieve to edit. I am trying to edit several rows then save it at one go.
I have two models of Grade and Product described below
class Grade(models.Model):
GRADE_TYPES = (
("p", "Primary Grade"),
("S", "Secondary Grade"),
)
grade_name = models.TextField(max_length=10, unique = True)
grade_type = models.CharField(max_length=1, choices=GRADE_TYPES)
class Meta:
ordering = ['grade_name']
def __str__(self):
return self.grade_name
def get_absolute_url(self):
return reverse('grade_list')
class Product(models.Model):
production_date = models.DateField()
grade = models.ForeignKey(Grade, on_delete=models.SET_NULL, null=True)
kilos = models.DecimalField(decimal_places=1, max_digits = 5)
products=[]
class Meta:
unique_together =('production_date','grade')
ordering = ['-production_date']
def __str__(self):
return self.production_date
def get_absolute_url(self):
return reverse('production_list')
My form
class Add_ProductForm(forms.ModelForm):
class Meta:
model = Product
fields = '__all__'
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
product_date = datetime.today()-timedelta(days=1)
grades = Grade.objects.all()
for grade in grades:
product = Product.create(product_date,grade,0)
product.save()
class Add_product(View):
template_name = 'create_daily_product.html'
Product_Formset = modelformset_factory(Product, form=Add_ProductForm)
def get(self,request, *args, **kwargs):
context ={
'product_form':self.Product_Formset(queryset =
Product.objects.filter(kilos=0.0)),
}
return render(request,self.template_name,context)
def post(self,request, *args, **kwargs):
product_formset = self.Product_Formset(self.request.POST)
if product_formset.is_valid:
for products in product_formset:
products.save() # The Product could not be changed because
the data didn't validate.
return HttpResponseRedirect(reverse("success.url"))
else:
context ={
'product_form':self.Product_Formset(),
}
return render(request,'create_daily_product.html',context)
I populate the model Product with initial data and then retrieve it so that I can change the quantities of kilos to other values. I then edit the kilos successfully but on clicking update to save, I get the error message "The Product could not be changed because the data didn't validate". The form appears to be valid but on starting to save it fails.
I should render the data to edit, update it and then save it. The first two happen successfully, but not the last. I also want to only save the rows where the kilos>0, but cannot test that since the saving fails.

Answer 1

it probably because this line
if product_formset.is_valid:
it supposed to be
if product_formset.is_valid():
also, check the indentation for functions in your model and modelform.
your models should be
class Grade(models.Model):
GRADE_TYPES = (
("p", "Primary Grade"),
("S", "Secondary Grade"),
)
grade_name = models.TextField(max_length=10, unique = True)
grade_type = models.CharField(max_length=1, choices=GRADE_TYPES)
class Meta:
ordering = ['grade_name']
def __str__(self):
return self.grade_name
def get_absolute_url(self):
return reverse('grade_list')
class Product(models.Model):
production_date = models.DateField()
grade = models.ForeignKey(Grade, on_delete=models.SET_NULL, null=True)
kilos = models.DecimalField(decimal_places=1, max_digits = 5)
products=[]
class Meta:
unique_together =('production_date','grade')
ordering = ['-production_date']
def __str__(self):
return self.production_date
def get_absolute_url(self):
return reverse('production_list')
while your modelform:
class Add_ProductForm(forms.ModelForm):
class Meta:
model = Product
fields = '__all__'
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
......