matrix (https://matrix.org/) is a more modern messaging protocol than XMPP; it revolves around HTTP and JSON because it's the most logical today the way XMPP is based on XML because it was the most logical at the time. Let's hope they can achieve something here !
I also wanted to come in here and promote matrix. You can use it internally, or you can federate it. It takes a lot of concepts from XMPP, and is essentially json over http with an "eventually consistent" synchronization between clients and servers.
