Rails attr_accessible :object vs :object_id

Question

A User has_one Account. When setting up attr_accessible on the User model is it better to protect :account, :account_id or both?

attr_accessible :account

or

attr_accessible :account_id

or

attr_accessible :account, :account_id

I feel like both is the way to go (as it's more secure) even though it feel less DRY.

Update to give more background

Just to give a bit more background on why I'm asking. I, like most ppl, saw what happened to Github so we're going through our app and locking it down a little tighter.

In the process of doing this I found tests in which we pass in account

User.create account: account

and where we passed in account_id:

User.create account_id: account.id

My options were to either change them all to be consistant or change attr_accessible to allow either. I decided to change them all to be consistant. But this got me worried that we were perhaps using both methods throughout our app and I might break our app by only allowing one or the other.

I did misspeak when I said using both is more secure. It was a long day.

Answer 1

There's no right answer for this one, though it does depend on how you intend to update this user. attr_accessible :account will allow you to mass-assign the account directly like this:

user.update_attributes(:account => account)

Helpful if you already have an account object that you want to associate to the user along with a lot of other attributes. On the other hand, attr_accessible :account_id would be more appropriate if you were assigning the account's ID, as from a dropdown or some other form element:

user.update_attributes(params[:user]) # params[:user][:account_id] is a part of this hash

This latter case is generally considered more dangerous and was part of the problem with Github's recent security issue: that you can post any account_id you like, including an account that doesn't belong to you, and your user will be assigned to it.

So overall I would go for the former and do a look-up to ensure the account is one that you expect, but as I said at the beginning, you can go either way on this one depending on how you intend to use it.