Rack::OauthProxy 
Note
This project is archived because I no longer actively use it, and there seems to be no recent activity from other users either. If you are still using it and would like to take over maintenance, please contact me somewhere.
Delegates OAuth authentication to other authentication server.
Usage
For Rails example:
class BlogsController < ApplicationController
use Rack::OauthProxy, url: "http://auth.example.com/oauth/token"
before_action :require_authorization
def show
...
end
private
def require_authorization
raise UnauthorizedError unless has_authorization?
end
# env["rack-oauth_proxy.response"] is a Faraday::Response object.
def has_authorization?
env["rack-oauth_proxy.response"].status == 200
end
end