How to send FCM notification to app from web

Question

I am developing chat app which is based on Firebase Database and Storage. Everything is working fine, but now I need implementation of FCM to receive notification on app when app is in background or foreground. I can't find a way to implement in PHP which listen any changes in firebase database and if there is any change then send push notification to app.

There is so many code which send notification from PHP, but none is based on Firebase database and even official documentation has Node.js guide which my shared hosting doesn't support.

I already implemented FCM code on my app side which is tested from Firebase Console.

Here is my Firebase database structure

Answer 1

Sending a push notification is only a matter of sending a post request to FCM servers.

Here is working example:

$data = json_encode($json_data);
//FCM API end-point
$url = 'https://fcm.googleapis.com/fcm/send';
//api_key in Firebase Console -> Project Settings -> CLOUD MESSAGING -> Server key
$server_key = 'YOUR_KEY';
//header with content_type api key
$headers = array(
    'Content-Type:application/json',
    'Authorization:key='.$server_key
);
//CURL request to route notification to FCM connection server (provided by Google)
$ch = curl_init();
curl_setopt($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, $data);
$result = curl_exec($ch);
if ($result === FALSE) {
    die('Oops! FCM Send Error: ' . curl_error($ch));
}
curl_close($ch);

Example of the JSON pay load:

[
    "to" => 'DEVICE_TOKEN',
    "notification" => [
        "body" => "SOMETHING",
        "title" => "SOMETHING",
        "icon" => "ic_launcher"
    ],
    "data" => [
        "ANYTHING EXTRA HERE"
    ]
]