How to render file in Rails 5 API?

Question

I have a single-page application written in React with Ruby on Rails back-end (API mode). Rails is also serving static files. I'm pointing Rails router to public/index.html, so my SPA could manage his own routing with react-router. This is common practice in order to make direct links and refresh to work.

routes.rb

match '*all', to: 'application#index', via: [:get]

application_controller.rb

class ApplicationController < ActionController::API
  def index
    render file: 'public/index.html'
  end
end

The problem is this doesn't work in API mode. It's just an empty response. If I change the parent class to ActionController::Base everything works as expected. But I don't want to inherit the bloat of full class, I need slim API version.

I've tried adding modules like ActionController::Renderers::All and AbstractController::Rendering without success.

also try calling from base, `ActionController::Base.helpers.render file: 'public/index.html'` — Md. Farhan Memon, May 11 '17 at 10:10
Yes, it literally renders the argument as html page. I even tried `render html: File.open('public/index.hml')` with no luck. — yeasayer, May 11 '17 at 10:11

score 27 · Accepted Answer · answered May 11 '17 at 10:20

If I change the parent class to ActionController::Base everything works as expected. But I don't want to inherit the bloat of full class, I need slim API version.

Yes, if you serve index from ApplicationController, changing its base class would affect all other controllers. This is not good. But what if you had a specialized controller to serve this page?

class StaticPagesController < ActionController::Base
  def index
    render file: 'public/index.html'
  end
end

This way, you have only one "bloated" controller and the others remain slim and fast.

score 1 · Answer 2 · answered May 11 '17 at 10:09

1

You could do

render text: File.read(Rails.root.join('public', 'index.html')), layout: false

answered May 11 '17 at 10:09

Kris

19,188
9
91
111

This renders the content of the file as text on webpage. Also tried the same with `html:` option. – yeasayer May 11 '17 at 10:15
Sorry, I do not understand the question then, but it seems you have an answer now :) – Kris May 12 '17 at 13:32
`text` is deprecated in Rails 5. – Pere Joan Martorell Aug 15 '19 at 12:55
@pj.martorell I think it is now `plain`. – Kris Aug 27 '19 at 08:17

Zan Zas · Answer 3 · 2021-05-07T06:32:41.193

I usually just redirect_to 'file path'.

def export
    # When the route coming to get 'some_report/export', to: 'greate_controller#export'
    # The file where you write or preparing, then you can redirect some path like : http://localhost:3000/public/tmpfile/report20210507.xlsx
    # And it will just redirect the file for you
    file_path = "public/tmpfile/report20210507.xlsx"
    redirect_to "#{root_url}#{file_path}"
end

For this example

root_url = "http://localhost:3000/"

score -1 · Answer 4 · answered Oct 22 '17 at 00:38

-1

This should work, and allow you to keep inheriting from ActionController::API--

class ApplicationController < ActionController::API
  def index
    respond_to do |format|
      format.html { render body: Rails.root.join('public/index.html').read }
    end
  end
end

The render logic changed for ActionController::API with Rails 5.

answered Oct 22 '17 at 00:38

common-nighthawk

657
7
10

It doesn't work `undefined method `respond_to' for #` – oaamados May 29 '19 at 23:11

How to render file in Rails 5 API?

4 Answers4

Linked