OneSignal Push Notifications for Laravel 5
Introduction
This is a simple OneSignal wrapper library for Laravel. It simplifies the basic notification flow with the defined methods. You can send a message to all users or you can notify a single user. 
Before you start installing this service, please complete your OneSignal setup at https://onesignal.com and finish all the steps that is necessary to obtain an application id and REST API Keys., (*1)
Installation
First, you'll need to require the package with Composer:, (*2)
composer require liliom/laravel-onesignal
Laravel 5.5 and up
You don't have to do anything else, this package uses the Package Auto-Discovery feature, and should be available as soon as you install it via Composer., (*3)
Laravel 5.4 and down
Update your config/app.php by adding the following service provider., (*4)
'providers' => [
    // ...
    // ...
    Liliom\OneSignal\OneSignalServiceProvider::class,
    // ...
];
Then, register class alias by adding an entry in aliases section, (*5)
'aliases' => [
    // ...
    'OneSignal' => Liliom\OneSignal\OneSignalFacade::class
];
Finally, publish the config file by running:, (*6)
php artisan vendor:publish --provider="Liliom\OneSignal\OneSignalServiceProvider"
php artisan vendor:publish --provider="Laravelme\Acquaintances\AcquaintancesServiceProvider"
The command above shall publish a configuration file named onesignal.php which includes your OneSignal authorization keys., (*7)
Configuration
Please fill the file config/onesignal.php.
app_id is your OneSignal App ID and rest_api_key is your REST API Key, where user_auth_key is optional., (*8)
Or alternatively you can fill your settings in .env file as the following:, (*9)
ONE_SIGNAL_APP_ID=
ONE_SIGNAL_REST_API_KEY=
Usage
Sending a Notification To All Users
You can easily send a message to all registered users with the command, (*10)
OneSignal::sendNotificationToAll("Some Message", $url = null, $data = null, $buttons = null, $schedule = null);
$url , $data , $buttons and $schedule fields are exceptional. If you provide a $url parameter, users will be redirecting to that url., (*11)
You can send a message based on a set of tags with the command, (*12)
OneSignal::sendNotificationUsingTags("Some Message", ["key" => "device_uuid", "relation" => "=", "value" => 123e4567-e89b-12d3-a456-426655440000], $url = null, $data = null, $buttons = null, $schedule = null);
Sending a Notification To A Specific User
After storing a user's tokens in a table, you can simply send a message with, (*13)
OneSignal::sendNotificationToUser("Some Message", $userId, $url = null, $data = null, $buttons = null, $schedule = null);
$userId is the user's unique id where he/she is registered for notifications. Read https://documentation.onesignal.com/docs/web-push-tagging-guide for additional details.
$url , $data , $buttons and $schedule fields are exceptional. If you provide a $url parameter, users will be redirecting to that url., (*14)
Sending a Notification To A Specific User via Email Address
If you are using the option to set the userId as email address of the user then use the following function, (*15)
OneSignal::sendNotificationToUserByEmail("Some Message", $email, $filters = [], $segment = ['All'], $url = null, $data = null, $buttons = null, $schedule = null, $smallIcon = null, $LargeIcon = null, $bigPicture = null, $androidAccentCircleColor = null, $androidAccentLedColor = null, $sound = null )
Sending a Notification To Segment
You can simply send a notification to a specific segment with, (*16)
OneSignal::sendNotificationToSegment("Some Message", $segment, $url = null, $data = null, $buttons = null, $schedule = null);
$url , $data , $buttons and $schedule fields are exceptional. If you provide a $url parameter, users will be redirecting to that url., (*17)
Sending a Custom Notification
You can send a custom message with, (*18)
OneSignal::sendNotificationCustom($parameters);
### Sending a Custom Notification
Sending a async Custom Notification
You can send a async custom message with, (*19)
OneSignal::async()->sendNotificationCustom($parameters);
Please refer to https://documentation.onesignal.com/reference for all customizable parameters., (*20)