This gem allows Rack based APIs to be set to read only. At the most basic it can be used like this from your config.ru:

require 'rack/read_only'

use Rack::ReadOnly, {
  active: ENV["READ_ONLY"] == "1",
  response_body: '{ "error": "This API is currently in read only mode." }'
run MyApp

When in read only mode the API will continue to respond to GET, HEAD, and OPTIONS requests as normal, but reject POST, PUT, DELETE, and PATCH requests with the body specified, and a 503 error code.


Add this line to your application's Gemfile:

gem 'rack-read_only'

And then execute:

$ bundle

Or install it yourself as:

$ gem install rack-read_only


After checking out the repo, run bin/setup to install dependencies.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release to create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.


  1. Fork it ( https://github.com/jellybob/rack-read_only/fork )
  2. Create your feature branch (git checkout -b my-new-feature)
  3. Commit your changes (git commit -am 'Add some feature')
  4. Push to the branch (git push origin my-new-feature)
  5. Create a new Pull Request

Any new builds should pass the tests on Travis