environment.rb

# environment.rb
#
# These are models you should define. (you can change the model name, of course)
# * Oauth2::AccessToken

Rails::Initializer.run do |config|
  :
  require 'rack/oauth2'
  oauth2_authenticator = lambda do |request|
    access_token = Oauth2::AccessToken.find_by_token(request.access_token)
    if access_token.blank?
      request.invalid_token! "Given access token is invalid."
    elsif access_token.expired?
      request.expired_token! "Given access token has been expired."
    elsif access_token.revoked?
      request.invalid_token! "Given access token has been revoked."
    end
  end
  config.middleware.insert_before(RestfulJsonpMiddleware, Rack::OAuth2::Server::Resource, "server.example.com", &oauth2_authenticator)
  :
end