5 Steps to publish on a facebook wall using php

Since Facebook has stopped supporting Java we need to use PHP for now to post on a wall.

According to facebook Wiki posting on a  wall is very confusing and very difficult to write a program to publish on a wall.

I spent around 2 weeks reading many articles and many documents, Wiki on facebook but in vein and tried many ways and finally I got one workable model. Below are 5 simple steps to publish on a Facebook wall.

Step1: Login to Facebook to Create a Facebook App

First login to Facebook and goto the url http://www.facebook.com/developers/ then

Click on “+ Set Up New Application” button to start creating the application as shown below.

Provide the application name, click agree for facebook terms and click on “Create Application” button.

Fill in application Name

Now Application is created for you. Just copy the Application API Key, Application Secret and Application ID details which will be used to write the application code.

Fill the Name and Description of your application in About Link.

Now Click on Website Link to get API Key

Now goto Facebook Integration link and enter any url. Here is where you will get Secret Key.

Enter the Canvas URL and page name. This will be the return URL of your Application.

Facebook Application Facebook Integration

That’s it You now just successfully create a Facebook Application, now lets work on program

Then click on Save. That’s it we have created a facebook application with an Iframe.

Now Copy Application API Key, Application Secret and Application ID details which will be used to write the application code.

Now download the php library from facebook “http://blog.theunical.com/wp-content/uploads/2010/05/facebook-platform.tar.gz”

Step2: Generate One Time Token to generate Session key

How to generate One Time Session key:

Run below URL to get temporary token for the particular user by logging into Facebook.

https://login.facebook.com/code_gen.php?api_key=API_KEY&v=1.0

Note: Please replace “API_KEY” with your application API key from above page.

Then we will get a temporary token key.

This is one time token key that we can use to generate a permanent session key. Careful! Don’t try to execute this programs many times

Step3: Generate one time session key (permanent session key)

Below is the sample PHP code to generate one time session key.

01

<?php

02

03	// FB_APIKEY is your facebook application api key

04

05	// FB_SECRET is your application secrete key

06

07	$FB_APIKEY="YOUR_API";

08

09	$FB_SECRET="YOUR_SECRET";

10

11	$fb = new FacebookRestClient($FB_APIKEY, $FB_SECRET);

12

13	$testtoken= "ONETIMETOKEN"; // Replace this value with your Token Value

14

15	$result = $fb->call_method('facebook.auth.getSession',

16

17	array('auth_token' => $testtoken, 'generate_session_secret' => true));

18

19	echo "<br /><pre>";

20

21	print_r($result);

22

23	echo $session_key = $result['session_key'];

24

25

?>

(OR)

For example, the full URL for logging in a user could be:

http://www.facebook.com/login.php?api_key=YOURAPIKEY&connect_display=popup&v=1.0&next=http://www.facebook.com/connect/login_success.html&cancel_url=http://www.facebook.com/connect/login_failure.html&fbconnect=true&return_session=true&session_key_only=true&req_perms=read_stream,publish_stream,offline_access

If the user is redirected to the URL specified by the next parameter, then Facebook grants your application a session. This session is appended to the URL as a JSON-decodable object of the form:

&session={“session_key”:”SESSIONKEY”, “uid”:USERID, “expires”:0 || UNIXTIME, “secret”:”SESSIONSECRET”}

In continuing with the above example, the redirect for a successful login would be:

http://www.facebook.com/connect/login_success.html?session=%7B%22session_key%22%3A%223.kxhAu6W0qo_bLGjmdWrgfw__.86400.1243443600-688626964%22%2C%22uid%22%3A%22688626964%22%2C%22expires%22%3A1243443600%2C%22secret%22%3A%220NVNMxpO6jVyDcVCvVv_PA__%22%2C%22sig%22%3A%22ac1c0c77c137567389defea70481b7aa%22%7D

If the user grants your application the offline_access extended permission, 0 gets returned for expires and the session never expires unless the user removes the application. In this case, you should store the session key so the user doesn’t have to log in the next time he or she launches your application.

Note: The above code will execute only once. We should note down the above session key, This will be used to auto login into the application.

If you don’t save these session key values you should generate other token key to create one time session key.

We can use the token only once.

Step4: Setting Permission for wall

Giving Permission to your application to publish on facebook wall. To give permission just replace the your API key in below URL and execute in browser.

http://www.facebook.com/login.php?api_key=APIKEYXxxxxxxxxxxxxxxxxx&connect_display=popup&v=1.0&next=http://www.facebook.com/connect/login_success.html&cancel_url=http://www.facebook.com/connect/login_failure.html&fbconnect=true&return_session=true&req_perms=read_stream,publish_stream,offline_access

Then you must see the below 3 Screens

If you don’t see the below then your call back URL or Canvas URL must be incorrect, please check again your application settings and execute the URL again.

Then on final page, you will see a success message.  That’s it you have given permission for read_stream,publish_stream and offline_access.

Step5: Publishing the message on Facebook Wall

PHP Code to create facebook object with onetime session key and publishing the message on Facebook Wall.

01

<?php

02

03	define('FB_APIKEY', 'YOUR_APIKEY');

04

05	define('FB_SECRET', 'YOUR_SECRET');

06

07	define('FB_SESSION', 'YOUR_SESSION_key');

08

09	require_once('facebook-platform/php/facebook.php');

10

11	echo "post on wall";

12

13

try {

14

15	$facebook = new Facebook(FB_APIKEY, FB_SECRET);

16

17	$facebook->api_client->session_key = FB_SESSION;

18

19	$fetch = array('friends' =>

20

21	array('pattern' => '.*',

22

23	'query' => "select uid2 from friend where uid1={$user}"));

24

25	echo $facebook->api_client->admin_setAppProperties(array('preload_fql' => json_encode($fetch)));

26

27	$message = 'From My App: publish steven on facebook';

28

29	if( $facebook->api_client->stream_publish($message))

30

31	echo "Added on FB Wall";

32

33	} catch(Exception $e) {

34

35	echo $e . "<br />";

36

37

}

38

39

?>

Now you will see the post on wall Great.

So thrilling isn’t we can also publish photos videos on wall.

In my next post see how to publish images and videos to facebook is done

http://blog.theunical.com/facebook…/add-picture-on-facebook-wall-using-php/

http://blog.theunical.com/facebook…/post-video-on-facebook-wall-using-php/

See here how to publish on facebook page as a facebook user

http://wiki.developers.facebook.com/index.php/Stream.publish