Since this seems to be resonating with a lot of folks, I'll also follow with something more constructive:
What I'd like to see is a messaging system that gets the basics right, and that's deeply aware that it's AP out of CAP. Messages are inherently commutative (think CRDTs) and can be received in arbitrary order; people on two sides of a partition should have no trouble reconciling coherent logs regardless of if there was a two minute netsplit or someone was backpacking for two weeks. I'm looking for any existing stuff that suits this, and willing to collaborate on making it if it needs to be made!
You may find happiness with matrix (https://matrix.org/). It's basically a "message synchronization protocol" done with today's technology (HTTP+JSON). The synchronization approach versus the messages being sent on the socket actually makes me think about mosh vs ssh.
Thanks for the suggestion. I skimmed their docs before briefly; I'm giving it a second look now, and realizing I passed by way too quickly last time.
It looks like they did tackle acausality head-on; I like what I see about previous message IDs being included in https://matrix.org/docs/spec/#pdus
Nervous about ever christening JSON "today's technology". JSON has the same problem XML in XMPP does: can't tunnel binary e.g. video without extreme backbending (jingle for XMPP is pretty much a textbook example of "too much friction -> not fit for purpose and near zero adoption"). But it looks like matrix is pluggable on transports, too, so that's potentially a sweet spot for lazy REST clients and powerful performance situations to coexist.
... And I popped into their self-hosted chat room. Observation 1: It works (!). Observation 2: the devs are dogfooding and seem both knowledgeable and friendly :) I haven't taken the leap to self-host yet (will later!); but from preliminaries, matrix is looking remarkably solid and well thought out. I'm going to try to build something with this! Thanks again for the link!
> Nervous about ever christening JSON "today's technology".
I use this to say "XML was the hot when XMPP was created, the way JSON is the hot today, when Matrix is created". I 100% agree with you that using a non-binary-friendly format sucks for pretty much anything that goes beyond plain text messaging:
- encryption
- files/emoticons/voice
- on the server side, any routing stuff
But still, like XMPP I hope this will not be enough to hamper its development.
> jingle for XMPP is pretty much a textbook example of "too much friction -> not fit for purpose and near zero adoption"
Amen to that. XMPP is basically an entity-to-entity messaging protocol, and yet because it can't handle binary there needs to be a negotiation step and yet another connection for binary stuff... blah.
The client-server API of Matrix only uses http+json as the lowest common denominator baseline for compatibility. Folks are more than welcome to implement custom more efficient transports like COAP/CBOR or whatever.
The server-server API is currently just targetting https+json just for expedience in getting started, but nothing to stop us negotiating more efficient transports in future - capn proto has come up a lot in conversation as a possible option. Handling signing is a bit more fun as we currently rely on signing canonical json, but surmountable.
As for binary transfers... well, random blobs are just handled as pure HTTP with a mimetype currently :)
What I'd like to see is a messaging system that gets the basics right, and that's deeply aware that it's AP out of CAP. Messages are inherently commutative (think CRDTs) and can be received in arbitrary order; people on two sides of a partition should have no trouble reconciling coherent logs regardless of if there was a two minute netsplit or someone was backpacking for two weeks. I'm looking for any existing stuff that suits this, and willing to collaborate on making it if it needs to be made!