How to develop Push Notification in PHP?

Code:

<?php



// API access key from Google API's Console

define( 'API_ACCESS_KEY', 'YOUR-API-ACCESS-KEY-GOES-HERE' );





$registrationIds = array( $_GET['id'] );



// prep the bundle

$msg = array

(

 'message' => 'here is a message. message',

 'title' => 'This is a title. title',

 'subtitle' => 'This is a subtitle. subtitle',

 'tickerText' => 'Ticker text here...Ticker text here...Ticker text here',

 'vibrate' => 1,

 'sound' => 1,

 'largeIcon' => 'large_icon',

 'smallIcon' => 'small_icon'

);



$fields = array

(

 'registration_ids' => $registrationIds,

 'data' => $msg

);

 

$headers = array

(

 'Authorization: key=' . API_ACCESS_KEY,

 'Content-Type: application/json'

);

 

$ch = curl_init();

curl_setopt( $ch,CURLOPT_URL, 'https://android.googleapis.com/gcm/send' );

curl_setopt( $ch,CURLOPT_POST, true );

curl_setopt( $ch,CURLOPT_HTTPHEADER, $headers );

curl_setopt( $ch,CURLOPT_RETURNTRANSFER, true );

curl_setopt( $ch,CURLOPT_SSL_VERIFYPEER, false );

curl_setopt( $ch,CURLOPT_POSTFIELDS, json_encode( $fields ) );

$result = curl_exec($ch );

curl_close( $ch );



echo $result;

PHP Code:

<?php

function sendMessage($data, $target, $serverKey){
   //FCM api URL
   $rsp = [];
   $url = 'https://fcm.googleapis.com/fcm/send';
   //api_key available in Firebase Console -> Project Settings -> CLOUD MESSAGING -> Server key
   $server_key = $serverKey;
   $fields = array();
   $fields['data'] = $data;
   if(is_array($target)){
           $fields['registration_ids'] = $target;
       }else{
           $fields['to'] = $target;
   }
   //header with content_type api key
   $headers = array(
       'Content-Type:application/json',
       'Authorization:key='.$server_key
   );
   
   $ch = curl_init();
   curl_setopt($ch, CURLOPT_URL, $url);
   curl_setopt($ch, CURLOPT_POST, true);
   curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
   curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
   curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
   curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
   curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($fields));
   $result = curl_exec($ch);
   if ($result === FALSE) {
       //die('FCM Send Error: ' . curl_error($ch));
   }
   curl_close($ch);
   
   //print_r($result);
   return $result;
}