1. (Part 2)

2. From Part 1 We …  Signed up to be facebook developers Verified our facebook account. Added facebook developer app.  Setup a Heroku facebook application  Made a small modification to the app Downloaded a local copy of the source code to our computer. Pushed the change back to Heroku. Deployed the change to our app.

3. In Part 2 We Will …  Learn about the facebook graph API What information is available & how to access it  Learn how to modify our app to do cool things! Learn a little PHP Share some debugging strategies  All source code will be available on the class website!

4. What is the open graph?  A structure that connects objects (people, organizations, ideas) through relationships Yi ZhangSarah Tyler UCSC KnowsAttends

5. How does the open graph work?  Entities are identified via an ID Sarah Tyler ID: 100003271715513

6. How does the open graph work?  Attributes and relationships are stored with the entity Sarah Tyler ID: 100003271715513 Knows: 762859350 (Yi Zhang) Attends: 8686764758 (UCSC) Gender: Female Location: US Yi Zhang UCSC

7. What does facebook data look like?  User data displayed as JSON element https://graph.facebook.com/8686764758

8. What does facebook data look like?  A Handy PHP function to view an object print_r. (The ‘$basic’ object was created in the Heroku Sample app, we’ll show where in a few slides)

9. How to access public facebook data (with PHP)  To access the contents of the object ‘$basic’ Access an array using the [] notation ○ Ie. $basic[name] is the username ○ $basic[education] is an array of objects that represent eductation $basic[eductation][0] is the first eductation entity in the user profile $basic[eductation][0][school][id] is the id of the first education entity

10. How to access public facebook data (with PHP)  To get the graph data of an entity with id, $id, and load it into variable, $var

11. How to access public facebook data (with PHP)  To access the contents of the object ‘$var’ Access an stdObject using the -> notation ○ Ie. $var->[name] is the username

12. What if you want access to the private data?  First you need to authenticate your app  You need an access token A token is a variable that contains information for both the user and the app ○ Recall users had to approve what data each app could have access to ○ Users may give different permissions to different apps  <?php  define('YOUR_APP_ID', '189978644425758');  define('YOUR_APP_SECRET', '6c2dc6234e25244aa8edca98fb2c991f');  function get_facebook_cookie($app_id, $app_secret) {  $args = array();  parse_str(trim($_COOKIE['fbs_'. $app_id], '\\"'), $args);\\"'), $args);  ksort($args);  $payload = '';  foreach ($args as $key => $value) {  if ($key != 'sig') {  $payload.= $key. '='. $value;  }  if (md5($payload. $app_secret) != $args['sig']) {  return null;  }  return $args;  }  $cookie = get_facebook_cookie(YOUR_APP_ID, YOUR_APP_SECRET);   if (isset($cookie)){   $user = json_decode(file_get_contents(  'https://graph.facebook.com/me?access_token='.https://graph.facebook.com/me?access_token='.  $cookie['access_token']));  }   ?> App ID is public, used to identify your app App secret is private, like a password Gets the token

13. Another way to access facebook data  Heroku uses FBUtils.php A collection of open source facebook utility scripts  $token = FBUtils::login(AppInfo::getHome());  if ($token) {  // Fetch the viewer's basic information, using the token just provided  $basic = FBUtils::fetchFromFBGraph("me?access_token=$token");  $my_id = assertNumeric(idx($basic, 'id'));  }

14. What data is available? https://developers.facebook.com/tools/explorer See public data of any entity A text description of the fields Additional fields that can be accessed Create an access token to view private data

15. Getting User Permission (From Facebook’s tutorial)   My Facebook App   window.fbAsyncInit = function() {  FB.init({  appId :,  status : true,  cookie : true,  xfbml : true  });  };  (function(d){  var js, id = 'facebook-jssdk'; if (d.getElementById(id)) {return;}  js = d.createElement('script'); js.id = id; js.async = true;  js.src = "//connect.facebook.net/en_US/all.js";  d.getElementsByTagName('head')[0].appendChild(js);  }(document));   Login with Facebook  Permissions you are requesting from the user http://developers.facebook.com/docs/ reference/api/permissions/

16. Getting User Permission (Heroku)  Using the FBUtils, there is a function called FBUtils::login in FBUtils.php Permissions defined in the $scope variable ○ $scope = 'user_likes,user_photos,user_photo_video_tags'; Adding permissions requires the user to re- authenticate the app.

17. That’s all folks!  Questions? Need Help? Feel free to email skt@soe.ucsc.eduskt@soe.ucsc.edu  Handy Resources https://developers.facebook.com/docs/appsonf acebook/tutorial/ https://developers.facebook.com/docs/appsonf acebook/tutorial/ http://developers.facebook.com/docs/samples/ http://php.net/manual/en/funcref.php