firebase - php - send notification to everyone

Question

I want to send a background notification from fcm to all my users. This is my code, the only problem I've faced is that I have to put a token id. I need to send notification to all of my users without defining the token values

This is my code :

    <?php
define('API_ACCESS_KEY','Api');
 $fcmUrl = 'https://fcm.googleapis.com/fcm/send';
 $token='token';

     $notification = [
            'title' =>'title',
            'body' => 'body of message.',
            'icon' =>'myIcon', 
            'sound' => 'mySound'
        ];
        $extraNotificationData = ["message" => $notification,"moredata" =>'dd'];

        $fcmNotification = [
            //'registration_ids' => $tokenList, //multple token array
            'to'        => $token, //single token
            'notification' => $notification,
            'data' => $extraNotificationData
        ];

        $headers = [
            'Authorization: key=' . API_ACCESS_KEY,
            'Content-Type: application/json'
        ];


        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL,$fcmUrl);
        curl_setopt($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($fcmNotification));
        $result = curl_exec($ch);
        curl_close($ch);


        echo $result;
?>

It works fine and send notifications successfully, but how can I send notification to everyone?

Answer 1

It looks like there is no such feature to send notifications to all devices.

However, there is a workaround for your problem using topics. For this you will need to subscribe all users to a specific topic during the app startup.

FirebaseMessaging.getInstance().subscribeToTopic("your_topic");

Then you can send the notification to that topic so that the notification will be sent to all users.

'to' => '/topics/your_topic', // using topic instead of token

Answer 2

If i get your question.

You need to subscribe a Topic and then you just need to use that Topic. The users who subscribed to it, will get the notification.

Docs:-

Based on the publish/subscribe model, FCM topic messaging allows you to send a message to multiple devices that have opted in to a particular topic. You compose topic messages as needed, and FCM handles routing and delivering the message reliably to the right devices.

https://firebase.google.com/docs/cloud-messaging/android/topic-messaging

Answer 3

There are two ways to send notification to multiple users.

1. Create a topic with all the users in it and send the push to that topic. Example: https://firebase.google.com/docs/cloud-messaging/android/send-multiple

2. Send notification to application the package id. But this will send notification even to the non authenticated user.