How do you add a custom http header?

Question

I\'m looking to add custom http headers to a Ruby on Rails app that is currently hosted on Heroku.

Answer 1

In Rails 3 or above, simply

headers['Header-Name'] = 'header value'

works in controllers. This is even the recommended way; according to the documentation,

Response is mostly a Ruby on Rails framework implementation detail, and should never be used directly in controllers. Controllers should use the methods defined in ActionController::Base instead. For example, if you want to set the HTTP response’s content MIME type, then use ActionController::Base#headers instead of Response#headers.

And this is still true in Rails 6.0.