PHP Facebook Login Tutorial using Facebook SDK 4.0

Hello friends, welcome PHP Facebook Login Tutorial. In this tutorial we will create a PHP Facebook Login feature in your webpage.

PHP Facebook Login – Video Demo

If you liked the video or want to create a Facebook Login Feature to your web app then lets start.

The first thing we need to do is create an app in https://www.developers.facebook.com

Creating a Facebook App

Go to facebook developers and create a new app
You will get an App Id and an App Secret after creating the app.
Once you have created your app in facebook developers, go to your app’s dashboard
Click on settings
Click on add a platform
Select website

Because I will be using wamp server for this demonstration I have given site url as http://localhost.
And App Domain will also be localhost.
Fill the values and click save changes.

Setting Up Facebook SDK

Inside www folder of your wamp server directory, create a new directory.
I have created FacebookLoginPHP inside my www folder.
Inside that directory create a new directory named lib.
Now you need to get the Facebook SDK for PHP.
Download the facebook-php-sdk-v4-4.0-dev zip file and extract it.
Inside the extracted folder go to src folder.
Inside src folder you will find Facebook folder, copy this folder and paste it inside your lib folder which you had created.
Now thats it, your SDK is configured, lets move to coding part now.

Creating a PHP Facebook Login

Inside your project directory create a file named index.php.
Open the file to your text editor (I am using notepad++).
First we will define some constants that will be used for login.

<?php

define('APP_ID', 'YOUR APP ID');

define('APP_SECRET', 'YOUR APP SECRET');

define('REDIRECT_URL','http://localhost/FacebookLoginPHP/');

Fill the app id and app secret which you have already created.
In REDIRECT_URL you need to provide the address where you will be navigated after login attempt.
In this case we will be redirected to the same index.php file.
Now we will create the basic html structure for our document.

<?php

define('APP_ID', 'YOUR APP ID');

define('APP_SECRET', 'YOUR APP SECRET');

define('REDIRECT_URL','http://localhost/FacebookLoginPHP/');

<!DOCTYPE html>

<html>

<head>

<title>Facebook Login Sample</title>

</head>

<body>

</body>

</html>

Inside body we will write our php code.
First we will include the SDK

<?php

Author: Belal Khan

website: www.simplifiedcoding.net

//INCLUDING LIBRARIES

require_once('lib/Facebook/FacebookSession.php');

require_once('lib/Facebook/FacebookRequest.php');

require_once('lib/Facebook/FacebookResponse.php');

require_once('lib/Facebook/FacebookSDKException.php');

require_once('lib/Facebook/FacebookRequestException.php');

require_once('lib/Facebook/FacebookRedirectLoginHelper.php');

require_once('lib/Facebook/FacebookAuthorizationException.php');

require_once('lib/Facebook/GraphObject.php');

require_once('lib/Facebook/GraphUser.php');

require_once('lib/Facebook/GraphSessionInfo.php');

require_once('lib/Facebook/Entities/AccessToken.php');

require_once('lib/Facebook/HttpClients/FacebookCurl.php');

require_once('lib/Facebook/HttpClients/FacebookHttpable.php');

require_once('lib/Facebook/HttpClients/FacebookCurlHttpClient.php');

Now we will use the namespaces.

//USING NAMESPACES

use Facebook\FacebookSession;

use Facebook\FacebookRedirectLoginHelper;

use Facebook\FacebookRequest;

use Facebook\FacebookResponse;

use Facebook\FacebookSDKException;

use Facebook\FacebookRequestException;

use Facebook\FacebookAuthorizationException;

use Facebook\GraphObject;

use Facebook\GraphUser;

use Facebook\GraphSessionInfo;

use Facebook\HttpClients\FacebookHttpable;

use Facebook\HttpClients\FacebookCurlHttpClient;

use Facebook\HttpClients\FacebookCurl;

For using login with facebook we need to start session.

//STARTING SESSION

session_start();

Now we need to set our application using app id and app secret.

FacebookSession::setDefaultApplication(APP_ID,APP_SECRET);

Create an object of the FacebookRedirectLoginHelper class, it will take a parameter of a string.
This is string is the URL where you will get redirected after login attempt.

$helper = new FacebookRedirectLoginHelper(REDIRECT_URL);

After redirection we will get the session using our helper object.

$sess = $helper->getSessionFromRedirect();

If $sess is not null that means we have logged in successfully, else log in is unsuccessful.
We can check this using simple if else.

if(isset($sess)){

$request = new FacebookRequest($sess, 'GET', '/me');

$response = $request->execute();

$graph = $response->getGraphObject(GraphUser::className());

$name = $graph->getName();

}else{

echo '<a href="'.$helper->getLoginUrl().'">Login with Facebook</a>';

}

So if our $sess is not null we will get the user name of the account.
Else we will see a link saying login with facebook.
You can do some CSS to make it look better.
My final code with some CSS effect is.

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

<?php

define('APP_ID', '823531574391190');

define('APP_SECRET', 'c83f652eb093f3768f09ca5ebbdd7f03');

define('REDIRECT_URL','http://localhost/FacebookLoginPHP/');

<!DOCTYPE html>

<html>

<head>

<title>Facebook Login Sample</title>

<style>

body{

width:100%;

}

.facebooklogin{

font-size:100%;

font-family:arial;

display:block;

width:200px;

height:20px;

background-color:#142dac;

color: #FFFFFF;

text-decoration:none;

padding:20px;

border-radius:5px;

margin:0 auto;

text-align:center;

}

.facebooklogin:hover{

background-color:#4158cc;

}

.user{

font-size:100%;

font-family:arial;

display:block;

width:200px;

height:20px;

background-color:#142dac;

color: #FFFFFF;

text-decoration:none;

padding:20px;

border-radius:5px;

margin:0 auto;

text-align:center;

}

</style>

</head>

<body>

<?php

Author: Belal Khan

website: www.simplifiedcoding.net

//INCLUDING LIBRARIES

require_once('lib/Facebook/FacebookSession.php');

require_once('lib/Facebook/FacebookRequest.php');

require_once('lib/Facebook/FacebookResponse.php');

require_once('lib/Facebook/FacebookSDKException.php');

require_once('lib/Facebook/FacebookRequestException.php');

require_once('lib/Facebook/FacebookRedirectLoginHelper.php');

require_once('lib/Facebook/FacebookAuthorizationException.php');

require_once('lib/Facebook/GraphObject.php');

require_once('lib/Facebook/GraphUser.php');

require_once('lib/Facebook/GraphSessionInfo.php');

require_once('lib/Facebook/Entities/AccessToken.php');

require_once('lib/Facebook/HttpClients/FacebookCurl.php');

require_once('lib/Facebook/HttpClients/FacebookHttpable.php');

require_once('lib/Facebook/HttpClients/FacebookCurlHttpClient.php');

//USING NAMESPACES

use Facebook\FacebookSession;

use Facebook\FacebookRedirectLoginHelper;

use Facebook\FacebookRequest;

use Facebook\FacebookResponse;

use Facebook\FacebookSDKException;

use Facebook\FacebookRequestException;

use Facebook\FacebookAuthorizationException;

use Facebook\GraphObject;

use Facebook\GraphUser;

use Facebook\GraphSessionInfo;

use Facebook\HttpClients\FacebookHttpable;

use Facebook\HttpClients\FacebookCurlHttpClient;

use Facebook\HttpClients\FacebookCurl;

//STARTING SESSION

session_start();

FacebookSession::setDefaultApplication(APP_ID,APP_SECRET);

$helper = new FacebookRedirectLoginHelper(REDIRECT_URL);

$sess = $helper->getSessionFromRedirect();

if(isset($sess)){

$request = new FacebookRequest($sess, 'GET', '/me');

$response = $request->execute();

$graph = $response->getGraphObject(GraphUser::className());

$name = $graph->getName();

<?php echo "hi $name"; ?>

</div>

<?php

}else{

<a class="facebooklogin" href='<?php echo $helper->getLoginUrl();?>'>

<i class="fa fa-facebook"></i> Sign in with Facebook

</a>

<?php

}

</body>

</html>

Try running the project from your local host. Remember you need an active internet connection.
If you are having some trouble you can download my source code from below.

[easy_media_download url=”https://dl.dropboxusercontent.com/s/wwnjxmzc58jzzgu/php-facebook-login.zip?dl=0″ text=”Download Source”]