How do I select which attributes I want for active model serializers relationships

Question

I am using the JSONAPI format along with Active Model Serializers to create an api with rails-api.

I have a serializer which shows a specific post that

Answer 1

Instead of defining topics method, it's better to define separate topic serializer with explicitly specifying which attributes do you need to include. This is cleaner, and more maintainable approach then defining topics method.

class PostSerializer < ActiveModel::Serializer
  attributes :title

  belongs_to :domain
  belongs_to :user
  # remember to declare TopicSerializer class before you use it
  class TopicSerializer < ActiveModel::Serializer
    # explicitly tell here which attributes you need from 'topics'
    attributes :title
  end
  has_many :topics, serializer: TopicSerializer
end

Again, try to avoid defining methods for relations as much as possible, it's not clean, neither maintainable.

Answer 2

Just make sure to return a hash or array of hashes like so:

def videos
    object.listing_videos.collect do |lv|
      {
        id: lv.video.id,
        name: lv.video.name,
        wistia_id: lv.video.wistia_id,
        duration: lv.video.duration,
        wistia_hashed_id: lv.video.wistia_hashed_id,
        description: lv.video.description,
        thumbnail: lv.video.thumbnail
      }
    end
  end