CODEWITHSUNDEEP
ruby-on-railsjsonruby-on-rails-4rabl
Zach
Zach

Reputation: 1331

Rails 4 - How to render JSON regardless of requested format?

I'd like a Rails controller (all of them, actually, it's an API) to render JSON always always.

I don't want Rails to return "route not found", or try and fail to find an HTML template, or return 406. I just want it to automatically and always render JSON, e.g. from a RABL or JBuilder view.

Is this possible? Related questions seem to have answers that have the aforementioned downsides.

Upvotes: 31

Views: 17717

Answers (7)

Learn-ing
Learn-ing

Reputation: 31

I usually put it like this and it works. The lambda symbol ( => ) near :json is important.

def greet_action
  msg = {:greet => "hello"}
  render :json => msg
end

Upvotes: 0

Derek
Derek

Reputation: 1795

I tried the above solutions and it didn't solve my use case. In some of the controllers of my Rails 4.2 app, there was no explicit render called. For example, a service object was called and nothing was returned. Since they are json api controllers, rails was complaining with a missing template error. To resolve I added this to our base controller.

  def render(*args)
    options = args.first
    options.present? ? super : super(json: {}, status: :ok)
  end

It's a large app I'm converting to Rails 5, so this is just a safety measure as I removed the RocketPants gem that seemed to do this automatically.

As a note, my controllers inherit from ActionController::Base

Upvotes: 0

Artem P
Artem P

Reputation: 5331

It's just:

render formats: :json

Upvotes: 7

ruslan
ruslan

Reputation: 969

I had similar issue but with '.js' extension. To solve I did the following in the view: <%= params.except!(:format) %> <%= will_paginate @posts %>

Upvotes: 0

Peleg
Peleg

Reputation: 1234

You can use format.any:

def action
  respond_to do |format|
    format.any { render json: your_json, content_type: 'application/json' }
  end
end

Upvotes: 14

vee
vee

Reputation: 38645

You can add a before_filter in your controller to set the request format to json: 

# app/controllers/foos_controller.rb

before_action :set_default_response_format

protected

def set_default_response_format
  request.format = :json
end

This will set all response format to json. If you want to allow other formats, you could check for the presence of format parameter when setting request.format, for e.g:

def set_default_response_format
  request.format = :json unless params[:format]
end

Upvotes: 50

Maur&#237;cio Linhares
Maur&#237;cio Linhares

Reputation: 40333

Of course:

before_filter :always_json

protected

def always_json
  params[:format] = "json"
end

You should probably put this in a root controller for your API.

Upvotes: -1

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