Create through association (default params)

Given:

• You have a current_user
• You want to do something like current_user.comments.create(params) in the controller create method.

Instead of over-riding the CommentsController you just need to change the CommentResource like this:

class CommentResource < JSONAPI::Resource
  def self.create(context)
    CommentResource.new(context[:current_user].comments.new, nil)
  end
end

It is considered good practice to ensure the user can not be passed via your API so you should also update your creatable_fields method like this:

class CommentResource < JSONAPI::Resource
  def self.create(context)
    CommentResource.new(context[:current_user].comments.new, nil)
  end

  def creatable_fields(_context = nil)
    super - [:user]
  end
end

Also if to wanted to add a default parameter you could do something like:

class CommentResource < JSONAPI::Resource
  def self.create(context)
    CommentResource.new(context[:current_user].comments.new(status: 'active'), nil)
  end

  def creatable_fields(_context = nil)
    super - [:user, :status]
  end
end