Firebase Push Notification User valid or Invalid

 <?php

class Validate_firebase_token extends CI_Controller {

    function index() {

        //this code is useful for validation of token active or not 

        $firebase_push_notification_token = "FIREBASE_SERVER_APP_KEY";

        $headers = array

            (

            'Authorization: key=' . $firebase_push_notification_token,

            'Content-Type: application/json'

        );

        $data_for_android = [

            'registration_ids' => [

                "user_push_device_id_1",

                "user_push_device_id_2",

                "user_push_device_id_3"

            ],

            "dry_run" => TRUE

        ];

        $data_string = json_encode($data_for_android);

        $ch = curl_init();

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

        curl_setopt($ch, CURLOPT_POST, true);

        curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);

        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);

        curl_setopt($ch, CURLOPT_POSTFIELDS, $data_string);

        $response = curl_exec($ch);

        curl_close($ch);

        print_r($response);

    }

}

Reponses :

{

• multicast_id: -1,
• success: 1,
• failure: 2,
• canonical_ids: 0,
• results:

  [

  • {

    • message_id: "fake_message_id"

    },
  • {

    • error: "InvalidRegistration"

    },
  • {

    • error: "MismatchSenderId"

    }

  ]

}