Rails - how to get find domain url in a layout

Question

I had request.env['http_host'] working on localhost, but it causes an error when referenced in a layout page on heroku.

This request works in a view and displays the correct base url, but it causes an error when I move the code to the layout. Note - I'm using this to build absolute urls for images in html emails.

  <%= "#{request.env['HTTP_HOST']}/assets/email_header_image.png" %> 
  <%= image_tag "#{request.env['HTTP_HOST']}/assets/email_header_image.png" %>

error received:

ActionView::Template::Error (undefined method `env' for nil:NilClass):

Answer 1

If you want the host without the port, just use:

request.host

edit: Oops, I've just noticed that you're using the code in the view. I don't know if it is visible over there, I've only used it in controllers, but that's fairly simple to overcome by setting an instance variable.

Answer 2

1. In your controller, set an instance variable equal to the host:
   • @host = request.host
2. In your view, reference the instance variable using
   • <%= @host %>