I'm able to send a single push notification to APNs using cURL in PHP 7. This is fine for testing purposes, but I imagine sending many notifications in a short period of time would require a task queue with workers or to keep the connection with APNs open and not constantly open/close it.
Here is a google blog from 2013 describing the situation: https://cloudplatform.googleblog.com/2013/07/google-app-engine-takes-pain-out-of-sending-ios-push-notifications.html
What's the correct way of doing this, sending many push notifications to APNs in PHP 7 with Google Cloud?