How do you add a custom http header?
Use:
response.headers['HEADER NAME'] = 'HEADER VALUE'either in a specific method or to a before_filter method of your application controller depending on whether you need this to be added in a specific or to all of your responses.
UPDATE for Rails 5 - February 24th, 2018
As noted by @BrentMatzelle in the comments, for Rails 5:
response.set_header('HEADER NAME', 'HEADER VALUE')
In rails 5, the following solution works (in action methods)
response.set_header("Header-Name", "Header value")Reference: edgeapi
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::Baseinstead. For example, if you want to set the HTTP response’s content MIME type, then useActionController::Base#headersinstead ofResponse#headers.