Serialize With fast_jsonapi In A Rails App

Netflix put out a Ruby gem for super fast JSON serialization -- fast_jsonapi. It is great for serializing JSON responses for Rails API endpoints.

First, add gem 'fast_jsonapi' to your Gemfile and bundle install.

Then create the app/serializers directory for housing all of your JSON serializers.

Next you can create a serializer that corresponds to the model you want to serialize:

# app/serializers/recipe_serializer.rb
class RecipeSerializer
  include FastJsonapi::ObjectSerializer

  set_id :id
  attributes :name, :source_url
end

Last, use it to generate a JSON response in your controller:

# app/controllers/recipes_controller.rb
class RecipesController < ApiController
  def index
    render json: RecipeSerializer.new(@current_user.recipes)
  end
end

Requests to that endpoint will receive a response that looks something like this:

{
  data: [
    {
      id: 1,
      attributes: { name: "Old Fashioned", source_url: "http://..." },
    },
    {
      id: 2,
      attributes: { name: "Sazerac", source_url: "http://..." },
    },
  ]
}