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Comment by psycr | Hacker News Reader

It seems that the room message state is synced via a poller, as seen here: https://github.com/HashNuke/mogo-chat/blob/master/assets/jav...

I'm curious why you decided to implement this with a poller instead of with a Websocket. There's actually a reasonably detailed answer about how to do this sort of thing with Ember Data in the emberjs.com guides: http://emberjs.com/guides/models/frequently-asked-questions/...

Either way, how did you find working with Ember Data in general? What were the main sticking points?

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Here are some problems when using websockets

* Message loss * Latency * Authentication has to be done again over websockets - on every connect and reconnect. That means it is going to make the app resource hungry.

This is my first time with Ember. Experience was pleasant. The codebase is fast-changing, so StackOverflow replies become quickly outdated. You'll have to refer to the CHANGELOG.md file in their repos. And the Ember IRC channel is super-helpful.

Authentication has to be done again over websockets - on every connect and reconnect. That means it is going to make the app resource hungry.

Right, except that WebSockets only connect once in normal operation. You'd be surprised how resource hungry WebSockets aren't when compared to constant HTTP connections. Waiting 2.5 seconds for messages to arrive to all clients feels a little imperfect.

I live in a country where latency for websockets is 300-400ms for most hosting services (US/Europe). And the most common internet connection speed 512kbps.

Websockets disconnects for me frequently. So during reconnection, I'll have to reauth in my case.

Well it isn't difficult to detect that case and drop back to polling (which should have the exact same latency anyway). Aiming for lowest common denominator in this stuff seems unwise.

Totally agree. That's the right way to do it.

MogoChat is right now a one-man project, so supporting websockets and then polling seemed tedious, especially with something like Faye or SocketIO missing in Elixir. Phoenix Framework will soon have a high level abstraction over websockets (with Faye-like features). Once that's in, I'll be able to use it.

Why do you have to reauth? Websockets can carry cookies or query strings just like rest. How else do you prevent the need to reauth on every http query?

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