sinatra twitter client with oauth

sinatra-twitter-oauth-client.rb

# sinatra twitter client with oauth

require 'rubygems'
require 'sinatra'

# use http://github.com/moomerman/twitter_oauth gem
# gem sources -a http://gems.github.com
# gem install moomerman-twitter_oauth
require 'twitter_oauth'

# use memcached based session 
use Rack::Session::Memcache

set :host, 'localhost'
set :port, '4567'

before do
  @consumer_key = '<INSERT APP KEY>'
  @consumer_secret = '<INSERT APP SECRET>'
end

get '/' do

  if !has_access?
    session_clear()
    "<p><a href='/login'><img src='http://apiwiki.twitter.com/f/1242697715/Sign-in-with-Twitter-darker.png' /></a></p>"
  else
    client = get_client()
    
    if client.authorized?
      
      list = "<div>"
      client.user_timeline.each do |tweet|
        list << "<p><strong>#{tweet['user']['screen_name']}:</strong> #{tweet['text']}</p>"
      end
      list << "</div>"
      
      form = "<form action='/send' method='post'><label>What are you doing?</label><br /><textarea name='text'></textarea><br /><input type='submit' value='update' /></form>"
      
      return form + list + "<p><a href='/logout'>logout</a></p>"
    else
      session_clear()   
      "<p>not authorized!</p><p><a href='/login'><img src='http://apiwiki.twitter.com/f/1242697715/Sign-in-with-Twitter-darker.png' /></a></p>"
    end
    
  end
end

get '/login' do  
  if session['token'].nil? && session['secret'].nil? && session['url'].nil?
    client = get_client()
    @request_token = client.request_token(:oauth_callback => "http://#{options.host}:#{options.port}/callback")
    session['token'] = @request_token.token
    session['secret'] = @request_token.secret
    session['url'] = @request_token.authorize_url    
  end
  
  redirect session['url']
end

get '/callback' do  
  begin
    client = get_client()
    access_token = client.authorize(
      session['token'],
      session['secret'],
      :oauth_verifier => params[:oauth_verifier]
    )

    session['access_token'] = access_token.token
    session['access_secret'] = access_token.secret
    
    redirect '/'
  rescue OAuth::Unauthorized
    session_clear()
    redirect '/'
  end
end

post '/send' do
  if has_access?
    client = get_client()
  else
    redirect '/sent?err=1'
  end

  if client.authorized?
    client.update(params[:text])
    redirect '/sent'
  else
    redirect '/sent?err=1'
  end
end

get '/sent' do
  if params[:err] == '1'
    "your tweet was not sent!<br /><a href='/'>back</a>"
  else
    "your tweet was sent!<br /><a href='/'>back</a>"
  end
end

get '/logout' do
  session_clear()
  redirect '/'
end

def has_access?
  return session['access_token'] && session['access_secret']
end

def get_client()
  if !has_access?
    TwitterOAuth::Client.new(
      :consumer_key => @consumer_key,
      :consumer_secret => @consumer_secret)
  else
    TwitterOAuth::Client.new(
        :consumer_key => @consumer_key,
        :consumer_secret => @consumer_secret,
        :token => session['access_token'],
        :secret => session['access_secret'])
  end
end

def session_clear
  # yes, I don't know clean session :/
  session['token'] = nil
  session['secret'] = nil
  session['url'] = nil
  session['access_token'] = nil
  session['access_secret'] = nil
end