consider using X-Forwarded-For which is natively supported instead

Replace REMOTE_IP with X-Real-Ip if it's trusted (useful for Nginx)

Add this line to your application's Gemfile:

gem 'x-real-ip'

And then execute:

$ bundle

Or install it yourself as:

$ gem install x-real-ip

For rails just add it to Gemfile

For rack/sinatra

use XRealIp::Middleware

Or in Rack::Builder like this:

app = Rack::Builder.new do
  use XRealIp::Middleware
  use Raven::Rack
  map '/serve' do
    run Serve.new
  end
  map '/' do
    run App.new
  end
end

run app

Some ideas from https://github.com/rails/rails/blob/master/actionpack/lib/action_dispatch/middleware/remote_ip.rb

1. Fork it
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 new Pull Request