Rails 4 Strong Parameters - Handling Missing Model Params Hash

Question

Models: Posts and Users

Post belongs_to :user
User has_many :posts

Simple.

Assuming a few users exist, we visit the edit page for a Post.

Answer 1

I have a similar problem, and didn't like either of these answers much. In the rails documentation (http://guides.rubyonrails.org/action_controller_overview.html#more-examples) I see the following solution:

params.fetch(:blog, {}).permit(:title, :author)

Effectively you are supplying a default of {}, which seems to work well enough (at least for my situation).

Applying to your code, you'd have:

params.fetch(:post, {}).permit(:user_id)

I think this is reasonably clean, and seems to work in my code.