How to tell which format a controller has resolved to render

Question

In a rails controller action with the following code:

respond_to do |format|
  format.json{ render :json=>  {:status => 200, :response=>@some_resource} }
  format.html { redirect_to(some_resource_path)}
end

How can I log the format the controller will resolve i.e. 'HTML' or 'json'? format is of type Collector. Is there a way of getting a string denoting the format?

try params[:format] http://stackoverflow.com/questions/1671111/methods-for-limiting-the-rails-render-format-to-html — gayavat, Jun 22 '12 at 14:00

score 90 · Accepted Answer · answered Jun 22 '12 at 14:18

90

The method to access the format is:

controller.request.format

answered Jun 22 '12 at 14:18

Anil

3,899
1
20
28

10

Thanks Anil. So from the controller it is just request.format. – Undistraction Jun 22 '12 at 14:29
4

Better to use request.format, because controller.request.format throws undefined local variable or method `controller' – Nathan B Jul 28 '18 at 15:32

score 20 · Answer 2 · answered Apr 18 '19 at 23:02

20

in your controller you can do:

request.format
request.format.html?
request.format.js?
request.format.json?
# etc.

answered Apr 18 '19 at 23:02

localhostdotdev

1,795
16
21

I can't find any documentation on the available types or how they are built. Do you know where this is defined? – estani Aug 17 '20 at 12:24
Using the `byebug` gem in my controller, I was able to type `formats` in the debug session and I got this output: `[:js, :html, :text, :css, :ics, :csv, :vcf, :vtt, :png, :jpeg, :gif, :bmp, :tiff, :svg, :mpeg, :mp3, :ogg, :m4a, :webm, :mp4, :otf, :ttf, :woff, :woff2, :xml, :rss, :atom, :yaml, :multipart_form, :url_encoded_form, :json, :pdf, :zip, :gzip]` See this documentation: https://guides.rubyonrails.org/layouts_and_rendering.html – CWarrington Aug 05 '21 at 17:32

How to tell which format a controller has resolved to render

2 Answers2