Introduction

Google Cloud Messaging for Android (GCM): Helps the developer send data from servers and send data to our application. In other words when we send the request to the server then server returns a response to your application whenever new data is available instead of making a request to the server in a timely fashion.

Introduction to Google cloud messaging PHP and MySQL

This tutorial uses PHP as the server-side programming language and MySQL as the server-side database. The flow is provided by Android Google cloud Messaging.

Step 1

First an Android device sends its device id (sender id) to the GCM server for registration.

Step 2

When the registration is successfull the GCM Server returns a registration id to the Android device.

Step 3

After successfully receiving the registration id the device will send the registration id to our server.

Step 4

Store the registration id into the database.

Registering with Google Cloud Messaging.

Creating MySQL Database

1. Open the phpmyadmin panel by going to http://localhost/phpmyadmin and create a database called GCM.
2. Creating the database, select the database and execute the following query in the SQL tab to create the gcm_pushnotification_users table.
   1. CREATE TABLE IF NOT EXISTS `gcm_pushnotification_users ` (  
   2. `id` int(11) NOT NULL AUTO_INCREMENT,  
   3. `gcm_regid` text,  
   4. `name` varchar(50) NOT NULL,  
   5. `email` varchar(255) NOT NULL,  
   6. `created_at` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP,  
   7. PRIMARY KEY (`id`)  
   8. ) ENGINE=InnoDB DEFAULT CHARSET=latin1 AUTO_INCREMENT=1 ;  

Creating the PHP Project

Click on the xammp icon in the system tray then select PHP -> PHP Extensions -> Enable php_curl.

1. Go to your xammp folder and inside the htdocs folder create a folder called gcm_server_php.
2. Create a field called database_config.php. This field holds the database configuration and Google API key.

   database_config.php

   2.    /**  
   3.    * Database config variables  
   4.    */  
   5.    define(“DB_HOST”, “localhost”);  
   6.    define(“DB_USER”, “root”);  
   7.    define(“DB_PASSWORD”, “”);  
   8.    define(“DB_DATABASE”, “pushnotification”);  
   9.    /*  
   10.    * Google API Key  
   11.    */  
   12.    define(“GOOGLE_API_KEY”, “BIzajiCRLa4LjkiuytloQBcRCYcIVYA45048i9i8zfClqc”); // Place your Google API Key  
   13. ?>  
3. Create another file called database_connect.php. This file handles database connections and mainly opens and closes the connection.

   b_connect.php

   2.    class Database_Connect.{  
   3.   
   4.    public function connect() {  
   5.    require_once database_config.php ‘;  
   6.   
   7.    $con = mysql_connect(DB_HOST, DB_USER, DB_PASSWORD);  
   8.   
   9.    mysql_select_db(DB_DATABASE);  
   10.   
   11.    return $con;  
   12.    }  
   13.   
   14.      public function close() {  
   15.       mysql_close();  
   16.    }  
   17. }  
   18. ?>  
4. Create functions.php. This file contains the function to do database CRUD operations.

   functions.php
   

   2.    class Functions {  
   3.       private $db;  
   4.   
   5.   
   6.       function __construct() {  
   7.          include_once ‘./database_connect.php’;  
   8.   
   9.          $this->db = new Database_Connect();  
   10.          $this->db->connect();  
   11.       }  
   12.   
   13.       function __destruct() {  
   14.       }  
   15.  
   16.  
   17.  
   18.   
   19.       public function storeUser($name, $email, $gcm_regid) {  
   20.   
   21.          $result = mysql_query(“INSERT INTO gcm_pushnotification_users (name, email, gcm_regid, created_at) VALUES(‘$name’, ‘$email’, ‘$gcm_regid’, NOW())”);  
   22.   
   23.          if ($result) {  
   24.   
   25.             $id = mysql_insert_id();   
   26.             $result = mysql_query(“SELECT * FROM gcm_pushnotification_users WHERE id = $id”) or die(mysql_error());  
   27.   
   28.             if (mysql_num_rows($result) > 0) {  
   29.                return mysql_fetch_array($result);  
   30.             } else {  
   31.                return false;  
   32.             }  
   33.             } else {  
   34.                return false;  
   35.             }  
   36.          }  
   37.  
   38.  
   39.   
   40.          public function getAllUsers() {  
   41.             $result = mysql_query(“select * FROM gcm_pushnotification_users “);  
   42.             return $result;  
   43.          }  
   44.       }  
   45. ?>  
5. Create GCM.php. This file sends push notification requests to the GCM server.

   GCM.php
   

   2.    class GCM {    
   3.        
   4.  
   5.     
   6.       public function send_notification($registatoin_ids, $message) {    
   7.            
   8.          include_once ‘./database_connect.php’;    
   9.          $url = ‘https://android.googleapis.com/gcm/send’;    
   10.          $fields = array(    
   11.          ‘registration_ids’ => $registatoin_ids,    
   12.          ‘data’ => $message,    
   13.          );    
   14.          $headers = array(    
   15.          ‘Authorization: key=’ . GOOGLE_API_KEY,    
   16.          ‘Content-Type: application/json’    
   17.          );    
   18.            
   19.          $ch = curl_init();    
   20.          curl_setopt($ch, CURLOPT_URL, $url);    
   21.          curl_setopt($ch, CURLOPT_POST, true);    
   22.          curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);    
   23.          curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);    
   24.          curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);    
   25.          curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($fields));    
   26.          $result = curl_exec($ch);    
   27.          if ($result === FALSE) {    
   28.          die(‘Curl failed: ‘ . curl_error($ch));    
   29.       }    
   30.         
   31.       curl_close($ch);    
   32.       echo $result;    
   33.       }    
   34.    }    
   35. ?>   
6. Create a register_user.php file. This file is used to receive requests from the Android device and stores the user in the database.

   register_user.php

   2.    $json = array();  
   3.  
   4.  
   5.  
   6.   
   7.    if (isset($_POST[“name”]) && isset($_POST[“email”]) && isset($_POST[“regId”])) {  
   8.       $name = $_POST[“name”];  
   9.       $email = $_POST[“email”];  
   10.       $gcm_regid = $_POST[“regId”];   
   11.   
   12.       include_once ‘./functions.php’;  
   13.       include_once ‘./GCM.php’;  
   14.       $db = new Functions();  
   15.       $gcm = new GCM();  
   16.       $res = $db->storeUser($name, $email, $gcm_regid);  
   17.       $registatoin_ids = array($gcm_regid);  
   18.       $message = array(“product” => “shirt”);  
   19.       $result = $gcm->send_notification($registatoin_ids, $message);  
   20.       echo $result;  
   21.       } else {  
   22.          echo ” user details missing”;  
   23.    }  
   24. ?>  
7. Create a send_pushnotification_message.php file. This file is used to send push notification to an Android device to send a request to the GCM server.

   send_pushnotification_message.php
   

   2.    if (isset($_GET[“regId”]) && isset($_GET[“message”])) {  
   3.       $regId = $_GET[“regId”];  
   4.       $message = $_GET[“message”];  
   5.       include_once ‘./GCM.php’;  
   6.       $gcm = new GCM();  
   7.       $registatoin_ids = array($regId);  
   8.       $message = array(“price” => $message);  
   9.       $result = $gcm->send_notification($registatoin_ids, $message);  
   10.       echo $result;  
   11.    }  
   12. ?>  
8. Last and finally create a file called index.php and paste the following code into it. The following code will create a simple admin panel to list all the user devices and provides a panel to send push notification to individual devices.

   index.php
   

   1.   
   2.   
   3.      
   4.         
   5.       “Content-Type” content=“text/html; charset=UTF-8”>  
   6.       >  
   7.       >  
   8.          $(document).ready(function(){  
   9.          });  
   10.          function sendPushNotification(id){  
   11.          var data = $(‘form#’+id).serialize();  
   12.          $(‘form#’+id).unbind(‘submit’);  
   13.          $.ajax({  
   14.             url: “send_pushnotification_message.php”,  
   15.             type: ‘POST’,  
   16.             data: data,  
   17.             success: function(data, textStatus, xhr) {  
   18.                $(‘.txt_message’).val(“”);  
   19.             },  
   20.             error: function(xhr, textStatus, errorThrown) {  
   21.             }  
   22.          });  
   23.          return false;  
   24.       }  
   25.         
   26.      
   27.   
   29.    include_once ‘functions.php’;  
   30.     $db = new Functions();  
   31.    $users = $db->getAllUsers();  
   32.    if ($users != false)  
   33.    $no_of_users = mysql_num_rows($users);  
   34.    else  
   35.       $no_of_users = 0;  
   36.    ?>  
   37.    
       class=“container”>  

   38.       
       

       No of Devices Registered: echo

        $no_of_users; ?>  

   39.       
       

       ---

         

   40.      
       class

       =“devices”>  

   41.       
   42.          if ($no_of_users > 0) {  
   43.       ?>  
   44.       
   45.          while ($row = mysql_fetch_array($users)) {  
   46.       ?>  
   47.       
   48.   
   49.       
       
       “id“] ?>” name=“” method=“post” onsubmit=“return sendPushNotification(‘id“] ?>’)”>  

   50.       Name:  echo $row[“name”] ?>  
   51.       
       class=“clear”>

         

   52.       Email: echo $row[“email”] ?>  
   53.       
       class=“clear”>

         

   54.       
       class=“send_container”>  

   55.          “3” name=“message” cols=“25” class=“txt_message” placeholder=“Type message here”>  
   56.          “hidden” name=“regId” value=“gcm_regid“] ?>”/>  
   57.          “submit” class=“send_btn” value=“Send” onclick=“”/>  
   58.       

     

9.      
10.    

  

12. } else { ?>  
13.    
14.   
15.       No Users Registered Yet!  
16.    

  

17.      
18.      
19.