Ruby on rails - 嵌套属性：如何查找或创建嵌套模型

Question

I have a Bill model with nested Customer model. The Customer model has a phone number with a uniqueness validation on it. While creating the bill I want to fetch the existing record based on the phone number or create a new one if such doesn't exist. How should I do it in a RESTful way?

Answer 1

你会使用find_or_create_by方法，在你的情况下看起来像这样：

fetchedRecord = Bill.find_or_create_by_phone_number(customer.phone_number)

Answer 2

You can look at the find_or_create or find_or_create_by methods (which are dynamically created). A little Googling should get you there the rest of the way, I think.

Answer 3

It doesn't seem like these answers are what you are asking.

Forget about Rails, my question would be, what's the RESTful way to create a resource that might already exist? Should you POST to the resources (list) URL, and then expect a HTTP status code of 201 if the resource was created and a 200 if it already existed?

Seems like this should be spelled out in a standard somewhere.

By the way, this is how I am handling it--with status codes.

Answer 4

我把我放在关联回调before_add