How do you Skip an Object in an ActiveModel Serializer Array?

Question

I have searched through all the active model serializer (v 0.9.0) documentation and SO questions I can find, but can't figure this out.

I have objects which can be marked as "published" or "draft". When they aren't published, only the user who created the object should be able to see it. I can obviously set permissions for "show" in my controller, but I also want to remove these objects from the json my "index" action returns unless it is the correct user. Is there a way to remove this object from the json returned by the serializer completely?

In my activemodel serializer, I am able to user filter(keys) and overloaded attributes to remove the data, as shown using my code below, but I can't just delete the entire object (I'm left having to return an empty {} in my json, trying to return nil breaks the serializer).

I'm probably missing something simple. Any help would be much appreciated!

class CompleteExampleSerializer < ExampleSerializer

  attributes :id, :title
  has_many :children

  def attributes
     data = super
     (object.published? || object.user == scope || scope.admin?) ? data : {}
  end 

  def filter(keys)
    keys = super
    (object.published? || object.user == scope || scope.admin?) ? keys : {}
  end
end

Answer 1

That looks correct, try returning an array instead of a hash when you dont want any keys. Also, I don't think calling super is necessary b/c the filter takes in the keys.

Also, I don't think defining an attributes method is necessary.

Answer 2

I have chapters that can either be published or unpublished. They're owned by a story so I ended doing something like below.

has_many :unpublished_chapters, -> { where published: false }, :class_name => "Chapter", dependent: :destroy
has_many :published_chapters, -> { where published: true }, :class_name => "Chapter", dependent: :destroy

Inside of my serializer, I choose to include unpublished_chapters only if the current_user is the owner of those chapters. In ams 0.8.0 the syntax is like so.

def include_associations!
  include! :published_chapters if ::Authorization::Story.include_published_chapters?(current_user,object,@options)
  include! :unpublished_chapters if ::Authorization::Story.include_unpublished_chapters?(current_user,object,@options)
end

In my case, it's not so bad to differentiate the two and it saves me the trouble of dealing with it on the client. Our situations are similar but say you want to get all of the chapters by visiting the chapters index route. This doesn't make much sense in my app but you could go to that controller and render a query on that table.