render multiple queries as json in rails controller

Question

I have two rails controller actions:

  def show
    @project = Project.find(params[:id])
    render json: @project,
      :only => [:id, :compilation_id],
      :methods => :track_name,
      :include => {
        :user => { :only => [:id, :email] }
      }
  end

  def list_users
    render json: User.select(:id, :email)
  end

I would like to render them both in one response. What is the best way to go about doing this? I tried using the to_json method as described here but I read that that method is deprecated and I also noticed that it escapes the content which seems to be unnecessary. Any help is appreciated.

@dgilperez- No, your answer did not address the issue of rendering two models in one response. The info was useful, though, and I gave you an upvote. — laertiades, Dec 18 '14 at 14:31
Try jbuilder, I use it to render complicated json response all the time. — Raymond Liu, Dec 18 '14 at 15:00

score 1 · Answer 1 · answered Dec 05 '14 at 17:14

For the cases where you need json structures complicated enough for to_json to look readable, I recommend to use active_model_serializers gem.

You can then define two serializer classes like this:

class ProjectSerializer < ActiveModel::Serializer
  attributes :id, :compilation_id

  has_many :users
end

class UserSerializer < ActiveModel::Serializer
  attributes :id, :email
end

And then in your controller:

class ProjectsController < ApplicationController
  def show
    @project = Project.find(params[:id])
    render json: @project, serializer: ProjectSerializer, status: 200
  end
end

As a bonus track, you can even cache the response!

score 0 · Answer 2 · answered Dec 18 '14 at 14:28

The solution, of course, was pretty simple:

project = Project.select(:id, :compilation_id, :user_id, :genre_id, :ordering).find(params[:id])
render json: { :project => project,
               :users => User.select(:id, :email),
               :genres => Genre.select(:id, :name),
               :track_name => project.track_name
             }

render multiple queries as json in rails controller

2 Answers2