Cannot assign "'T Shirt for mens'": "CartProdVarient.cart

Models

class CartProduct(models.Model):
    cart_product_name = models.CharField(max_length=200)
    cart_holder = models.ForeignKey(User, on_delete=models.CASCADE)
    def __str__(self):
        return self.cart_product

class CartProdVarient(models.Model):
    cart_product = models.ForeignKey(CartProduct, on_delete=models.CASCADE)
    cart_prod_varient = models.CharField(max_length=200)
    def __str__(self):
        return self.cart_prod_varient

Views

 def add_cart(request):
    prod = Product.objects.get(id=request.POST.get('product_id'))

    CartProdVarient(cart_product=prod.product_name).save()

    return render(request, 'app/service-page.html')

Problem i want to assign some value to "cart_product" while its a Foreign key but it giving me error..

i want something like this :

 CartProdVarient(cart_product="T-Shirt", cart_prod_varient="small size").save()

T-Shirt is already in "cart_product_name"

CodePudding user response：

Your models are working fine. And the foreign key integration and model fields are correct. There is no error in the model.

The problem is with your views :

prod = Product( id = request.POST.get("product_id") )
#  this return an product object named prod , and this is a product object.

See your model CartProductVariant , you have defined the cart_product to be the foreignkey on the model CartProduct .


class CartProdVarient(models.Model):
    cart_product = models.ForeignKey(CartProduct, on_delete=models.CASCADE)
    cart_prod_varient = models.CharField(max_length=200)
    def __str__(self):
        return self.cart_prod_varient

Your first mistake . See your views in this line :

CartProdVarient(cart_product=prod.product_name).save()

You have defined relation with the CartProduct object but you are providing the name of the Product object . These two are different models. This might be the first case of error .

Your second mistake . Now see your views , in this line :

CartProdVarient(cart_product=prod.product_name).save()

You have defined the relation with the CartProduct , in Django whenever a foreign key is made the object is provided in the argument but you are providing the name of the product where as the cart_product will take the object of the CartProduct itself. It does not take the model fields , it takes the object itself.

change your code to this if the model CartProduct and Product are same :

CartProdVarient(cart_product=prod).save()

If the model CartProduct and Proudct are not same ( and I think they are not ) , you should change cart_product argument of Product object to CartProject object.

CartProdVarient(cart_product= CartPoduct.objects.get(id = request.POST.get("cart_product_id"))).save()

The whole code for the views need to be changed based on the model you have created and what is the relation you have defined on the models .

If the Product model and the CartProduct model are same ( and I don't think so they are ) . Use this code snippet .

def add_cart(request):
    prod = Product.objects.get(id=request.POST.get('product_id'))

    CartProdVarient(cart_product=prod).save()

    return render(request, 'app/service-page.html')

If they are different use this :

def add_cart(request):
    prod = CartProduct.objects.get(id=request.POST.get('cart_product_id'))

    CartProdVarient(cart_product=prod).save()

    return render(request, 'app/service-page.html')