ruby - Rails - Force model to be created via factory method -

I am using rail 4. I have a class, a car that has to be transported to within my app .

I want to access it using factory pattern:

  class CartFactory def self.obtain_cart_for_user (user) ... end end  

I want this approach because sometimes, I want to return to an existing car and sometimes a new construction (based on the cart, its content, whether it is still available on the basis of available products etc.) Want to do

It is quite easy.

However, I also want to make sure that any other future programmer does not directly direct the car, or through any other medium, organizations, such as:

  cart.new (...) user.carts.new (...) Cart.find (id) Cart.find_by_attribute (blah: blah) Cart.where (...) First  

Is there any way to prevent this from happening?

OK, this is possible:

  private_class_method: New < / Code> 

And of course, you are also ActiveRecord query method ( .panda , .where etc) But I think that seems like a good way to end up with irregular behavior if you want to go this route, make sure your app is fully tested first.

---

Another route will be for cart ActiveRecord :: Base (which I believe does that), and instead only Parts are required, such as ActiveRecord :: Perseverance if you are interested in diving deep, then see the parts involved in it.

---

Edit: An alternative cart must be made private within a module that only exposes CartFactory . There is no underlying syntax for any "private class", but again, do not know how well ActiveRecord will deal with that.

---

But in the end it is definitely the question that you want to do all this. In general, Ruby is not very good to protect you from yourself :) As explained in the subsequent linked reply, documentation and belief set a long way.