active_model_serializers/docs/general/getting_started.md

Getting Started

Installation

ActiveModel::Serializer is already included on Rails >= 5

Add this line to your application's Gemfile:

gem 'active_model_serializers'

And then execute:

$ bundle

Creating a Serializer

The easiest way to create a new serializer is to generate a new resource, which will generate a serializer at the same time:

$ rails g resource post title:string body:string

This will generate a serializer in app/serializers/post_serializer.rb for your new model. You can also generate a serializer for an existing model with the serializer generator:

$ rails g serializer post

The generated seralizer will contain basic attributes and has_many/has_one/belongs_to declarations, based on the model. For example:

class PostSerializer < ActiveModel::Serializer
  attributes :title, :body

  has_many :comments
  has_one :author

end

and

class CommentSerializer < ActiveModel::Serializer
  attributes :name, :body

  belongs_to :post_id

end

Rails Integration

AMS will automatically integrate with you Rails app, you won't need to update your controller, this is a example of how it will look like:

class PostsController < ApplicationController

  def show
    @post = Post.find(params[:id])
    render json: @post
  end

end