sinatra with rest-graph

app.rb

require "sinatra"
require "rest-graph"

enable :sessions
# set :raise_errors, false
# set :show_exceptions, false

FACEBOOK_SCOPE = 'read_stream'

unless ENV["FACEBOOK_APP_ID"] && ENV["FACEBOOK_SECRET"]
  abort("missing env vars: please set FACEBOOK_APP_ID and FACEBOOK_SECRET with your app credentials")
end

before do
  @rg = RestGraph.new(:access_token => session[:access_token],
                      :app_id       => ENV["FACEBOOK_APP_ID"],
                      :secret       => ENV["FACEBOOK_SECRET"])

  unless request.scheme == 'https'
    redirect "https://#{request.env['HTTP_HOST']}"
  end
end


helpers do
  def full_url path
    base = "#{request.scheme}://#{request.env['HTTP_HOST']}"
    base + path
  end
end

# the facebook session expired! reset ours and restart the process
error(RestGraph::Error::AccessToken) do
  redirect "/login"
end

get "/" do
  # if not logged in
  redirect "/login" unless @rg.authorized?

  @rg.get("me")
end

post "/" do
  redirect "/"
end

# facebook login
get "/login" do
  session[:access_token] = nil
  redirect @rg.authorize_url(:scope        => FACEBOOK_SCOPE, 
                             :redirect_uri => full_url("/callback"))
end

# facebook callback
get "/callback" do
  @rg.authorize!(:redirect_uri => full_url("/callback"), 
                 :code         => params[:code])
  session[:access_token] = @rg.access_token
  redirect '/'
end