I'd like to add chat to a web application I've been working on.
I've searched the Google documentation, but cannot find a way to send push notifications from a server to a web application running on Google's appengine standard environment.
The latest release notes indicate that websockets are not supported, and XMPP is not available either. For this project, there is no budget available for a third party solution, and I'd rather cut the code myself anyway.
What APIs are available to me? Surely there must be something or some way of building this sort of functionality?