Lumen error in FCM push notification api - php

Question

Create Api in lumen for FCM push notification bu I got the error
[numberTokensFailure:protected] => 7.
I am using this library : https://github.com/brozot/Laravel-FCM
Edited: If I pass token one by one insted of array then its working but in array its not working. please check my code and give me solution.
Api code :
public function push_notification() {
$optionBuilder = new OptionsBuilder();
$optionBuilder->setTimeToLive(60*20);
$notificationBuilder = new PayloadNotificationBuilder('my title');
$notificationBuilder->setBody('Hello world')
->setSound('default');
$dataBuilder = new PayloadDataBuilder();
$dataBuilder->addData(['a_data' => 'my_data']);
$option = $optionBuilder->build();
$notification = $notificationBuilder->build();
$data = $dataBuilder->build();
// You must change it to get your tokens
$tokens = Auth::select('token')->get()->toArray();
$downstreamResponse = FCM::sendTo($tokens, $option, $notification, $data);
$downstreamResponse->numberSuccess();
$downstreamResponse->numberFailure();
print_r($downstreamResponse);
$downstreamResponse->numberModification();
//return Array - you must remove all this tokens in your database
$downstreamResponse->tokensToDelete();
//return Array (key : oldToken, value : new token - you must change the token in your database )
$downstreamResponse->tokensToModify();
//return Array - you should try to resend the message to the tokens in the array
$downstreamResponse->tokensToRetry();
// return Array (key:token, value:errror) - in production you should remove from your database the tokens present in this array
$downstreamResponse->tokensWithError();
}

Answer 1

You need to loop through the array of tokens.
$tokens = Auth::select('token')->get()->toArray();
$numberOfSuccess = 0;
$numberOfFailure = 0;
if(count($tokens)>0){
for ($index = 0; $index < count($tokens); $index++) {
$singleToken = array($tokens[$index]['token']);
$downstreamResponse = FCM::sendTo($singleToken, $option, $notification, $data);
$numberOfSuccess = $numberOfSuccess + $downstreamResponse->numberSuccess();
$numberOfFailure = $numberOfFailure + $downstreamResponse->numberFailure();
}
}
Note:
This will take time if you have many tokens to send notification.
So, its better to use Laravel Queue Job functionality.