Facebook authentikation Koala::Facebook::AuthenticationError type: OAuthException, code: 190

Question

Authentication via Facebook does result in the following error message:

Koala::Facebook::AuthenticationError in AuthenticationsController#menu
type: OAuthException, code: 190, message: Malformed access token AQBiaE1v-pbSitzgNirHKSm7zNp3XoLAeHsvlFB626lARPBQCN98SBgIczjoRj3h8RQSVunm8gu-fHbO3H8-_9Ef9a5Lt00ixQ-wgum9p9FM5xN3WUvgc2BSyy1it2G4XlHNbQuwKYvsN-_7juH2NSXxMZmpaXh4qjjm13HWIjkYBWuyTIuJTJ7yUc97XixSMJtDbIIEBXfK52m_zIBTKvA4m8IoTOHDDoloeIhmARrGlMCmQG_vWZSMc.. (deleted the last characters by author) [HTTP 400]

Basically, the login seems to work but when I try to access my profile via @graph.get_object("me") the token is not accepted.

The console output for the 2nd working example seems to be ok.

I may get the wrong token, but why? It works with a fixed access_token generated on http://developers.facebook.com/tools/explorer

My Rails controller code:

class AuthenticationsController < ApplicationController

  APP_ID="1234"
  APP_SECRET="1234"
  APP_CODE="XXXX"
  SITE_URL="http://local.myapp.com:3000/"

  def index
    if session['access_token']
      @face='Logged in -> <a href="authentications/logout">Logout</a>'
      @graph = Koala::Facebook::API.new(session["access_token"])
    else
      @face='<a href="authentications/login">Login</a>'
    end
  end

  def login
        session['oauth'] = Koala::Facebook::OAuth.new(APP_ID, APP_SECRET, SITE_URL + 'authentications/callback')
        redirect_to session['oauth'].url_for_oauth_code()
  end

  def logout
    session['oauth'] = nil
    session['access_token'] = nil
    redirect_to '/'
  end

    def callback
        session['access_token'] = params["code"]
        redirect_to '/authentications/menu'
    end

  def menu
     @ok="Hi!"
     if session['access_token']
       @face='Logged in -> <a href="/authentications/logout">Logout</a>'
       @graph = Koala::Facebook::GraphAPI.new(session["access_token"])

       ## LEADS TO ERROR
       @graph.get_object("me")

     else
       @face='<a href="/authentications/login">Login</a>'
     end

  end
end

Another example using Sinatra which is working:

#let Bundler handle all requires
require 'bundler'
require 'uri'

Bundler.require(:default)

# register your app at facebook to get those infos
APP_ID     = 1234
APP_SECRET = '1234'

class SimpleRubyFacebookExample < Sinatra::Application

  use Rack::Session::Cookie, secret: 'this_adfkaTGDGHDHJJJksk_0898932311_secret'

  get '/' do
    if session['access_token']
      'You are logged in! <a href="/logout">Logout</a>'

      @graph = Koala::Facebook::API.new(session["access_token"])
      user = @graph.get_object("me")
      feed = @graph.get_connections("me", "feed", {:limit => 999})
    else
      'Logout successful <br> Click to login <a href="/login">Login</a>'
    end
  end

  get '/login' do
    session['oauth'] = Koala::Facebook::OAuth.new(APP_ID, APP_SECRET, "#{request.base_url}/callback")
    redirect session['oauth'].url_for_oauth_code( scope: "read_mailbox,read_stream")
  end

  get '/logout' do
    session['oauth'] = nil
    session['access_token'] = nil
    redirect '/'
  end

  get '/callback' do
    session['access_token'] = session['oauth'].get_access_token(params[:code])
    redirect '/'
  end
end

Answer 1

I could resolve the issue by using the omniauth and the omniauth-facebook gem.

Controller:

class AuthenticationsController < ApplicationController

  def create
    auth = request.env["omniauth.auth"]
    session['fb_auth'] = auth
    session['fb_access_token'] = auth['credentials']['token']
    session['fb_error'] = nil
    redirect_to authentications_menu_path
  end

  def menu
    if session["fb_access_token"].present?
      graph = Koala::Facebook::GraphAPI.new(session["fb_access_token"]) # Note that i'm using session here
      @profile_image = graph.get_picture("me")
      @fbprofile = graph.get_object("me")
      @friends = graph.get_connections("me", "friends")
    end
  end

  def logout
    session['fb_access_token'] = nil
    redirect_to root_path
  end

  protected

  def auth_hash
    request.env['omniauth.auth']
  end
end

Initializer (Omniauth.rb)

Rails.application.config.middleware.use OmniAuth::Builder do
  provider :facebook, '1234', '1233',
            :scope => 'read_stream'
end

Routes:

Rails.application.routes.draw do
  match 'authentications/index', via: [:get, :post]
  match 'authentications/login', via: [:get, :post]
  match 'authentications/logout', via: [:get, :post]
  match 'authentications/menu', via: [:get, :post]
  get '/auth/:provider/callback', to: 'authentications#create'
  root :to => "authentications#index"
end