OneSignal

This module provides integration with the free HTTP Web Push service from OneSignal, allowing visitors to subscribe to notifications and site owners to send notifications to the subscribers.

Drupal 8+ The Drupal 8+ version of this module is a complete rewrite.

At this point it allows site owners to integrate the OneSignal service through a configuration page. Once the module is configured, visitors can subscribe for notifications and site owners can create and send notifications.

The content and scheduling of the notifications is managed from the OneSignal website.

NOTE: The Drupal 8+ version is conceived for site builders and has a configuration page.

Requirements
Requires OneSignal PHP API library: https://github.com/norkunas/onesignal-php-api

For 2.x, module requires Guzzle 6. Support for Drupal 8 and 9. Uses v1 of OneSignal PHP API library above (https://github.com/norkunas/onesignal-php-api/blob/1.0/README.md).

For 3.x, module composer dependencies are more in line with the OneSignal PHP API library. Will be more bleeding edge and better support for Drupal 9 and 10. Uses v2 of OneSignal PHP API library above (https://github.com/norkunas/onesignal-php-api).

composer require symfony/http-client nyholm/psr7 norkunas/onesignal-php-api Documentation
For the Drupal 8+ version, this module has a README file with lots of information. Once the module is enabled, it makes available a help page.

Installation
It is highly recommended to install via composer.

Run the following command:

For 2.x release:

composer require 'drupal/onesignal:^2.0' For 3.x release:

composer require 'drupal/onesignal:^3.0' Drupal 7 (Legacy)
Going forward, development will be focused only on the Drupal 8+ version; therefore, the Drupal 7 version won't receive new features, improvements or support.

For the Drupal 7, documentation can be found at https://www.drupal.org/node/2710275.