Hacker News Reader

Comment by j4pe | Hacker News Reader

I had to roll my own chat system recently because the open source solutions out there were surprisingly insufficient - nothing seems to support websockets. Looking forward to the French contributions to the ecosystem!

For instance: at the moment Matrix server implementations expect clients like Riot to long-poll for JSON about each room/chat they're connected to. Alternatives like Prosody's XMPP server implementation dropped websocket support in favor of BOSH years ago.

I wonder why this is - maybe there's just less developer interest since chat has gone mobile, and mobile devices break ws connections so frequently? But it's obvious that chat clients like FB messenger, whatsapp, slack, etc are establishing ws connections.

Strange.

View on HN

Network overhead aside, long polling can be a pretty wonderful interface. “Give me what I don’t have yet, else let me know when there is something” makes for reliable transmission that is hard to screw up. Long polling requests can work idempotently and recover from network failures automatically. I think it’s an especially wise starting point.

There shouldn't be any overhead to long polling in comparison to websockets.

What about the HTTP headers?

If you are in a few group chats long polling is pretty efficient as there is almost always new content before the request times out.

> Prosody's XMPP server implementation dropped websocket support in favor of BOSH years ago.

You probably refer to the "old websocket" spec, new websockets are working well: https://prosody.im/doc/modules/mod_websocket

FB messenger actually uses MQTT last time I checked. In practice long poll HTTP is fine for most purposes, and meanwhile we have a GSoC project which should help improve on that this year (starting with push; then the protocol itself): https://summerofcode.withgoogle.com/organizations/?sp-search...

> Prosody's XMPP server implementation dropped websocket

Quite the opposite, but I admit the documentation is in need of improving to make the websocket functionality easier to discover.

It is in the default config file however, right next to BOSH.

Rocket Chat supports WebSockets. They don't advertise it very well, but if you look at the nginx config under the manual installation, you'll see that the 'upgrade' header is added when using nginx as a reverse proxy, presumably for ws support. Also, they have an experimental realtime API that uses WS and it looks like it's just the API that is still experimental, while WS are already in use for the regular desktop app and the new (still buggy) mobile app.

Matrix also supports WS actually but nobody bothers with it: https://github.com/matrix-org/matrix-doc/blob/master/drafts/...

WeeChat's (the IRC client, not the similarly-named Chinese messenger) relay protocol uses websockets. This is what enabled us to build Glowing Bear, a web frontend that connects to your WeeChat instance from your browser. I like to think of that as pretty cool :) (Disclosure: I'm one of the Glowing Bear developers, so of course I'd think it's cool)

Tigase XMPP server supports websocket out of the box as well (bosh as well)

Reply on news.ycombinator.com