Acronym aside, I think this is fantastic. These patterns (RPC, pubsub) have been around for a while now, and are fairly well understood. Formalizing them into a common, agnostic protocol that everyone can use is a huge win for all parties.
First, it's not just RPC, it's routed RPC. So you basically don't have to know who is providing the procedure and where it is. This also allows transparent fallbacks, hot swap and load balancing of the clients providing the procedure.
Another thing I like is the ease of use. If you used CORBA, XMLRPC or SOAP you know what a pain it is to get it work.
The Python and JS clients just work for me. Transparently: they even get errors back in their native form (ex: python get exception for an error occurring remotely). There is zero mapping to do: you start you client, you register your procedure, and you call it.
The fact is uses websocket is a cool thing too. First, it means you can use it in the browser, and not just nodejs, Python, C#, Java or PHP (but they all have interroperable clients!). But it also means it usually works on your network without the need to setup anything or bother your local sysadmin. And it can benefit from TLS.
It's really sweet.
My only beef is that the Python API is too verbose to my taste, and advance setup for crossbar.io can get complicated if you want to make it super secure (default settings are the equivalent of chmod 777).
Can you do nowadays easily do security for things that are not pure RPC? I remember looking at crossbar.io for the pub-sub features quite a while ago, and securing those was somewhere between a pain and impossible.
crossbar.io now have full featured authentification system, end to end encryption, and permissions isolated in realms. It's work, but yeah, you can secure things.
Securing a website is a lot of work too if you have to do it manually. I just don't do it much anymore, Django takes care of most of the issues for me, and barring some very bad decisions, I have little to actually worry about.
But crossbar doesn't have a django like framework. It's more like flask, express, sinatra...
I've been actually doodling the API of a high level framework on top of crossbar.io for 2 years now. But barring winning the lottery or starting a successful kickstarter, it's unlikely I will find the money to work on it for a year without interruption. It's crazy the amount of work that needs to be done to catch up with frameworks created a decades ago and improved by hundred of dev while field testing it :)
> These patterns (RPC, pubsub) have been around for a while now, and are fairly well understood. Formalizing them into a common, agnostic protocol that everyone can use is a huge win for all parties
You could have gotten that same passage out of a needlessly thick CORBA book a quarter century ago. (Unless you did, if this is sarcasm then I salute you).
The problem with adoption of "standard" RPC mechanisms has never been with the underlying transport layer. It's that an interface designed to "look like code" has exactly the property of code, which is that it's fragile in the face of evolution and tends to need to be rewritten every few years when the new generation of hackers gets bored with maintaining the crufty old junk.
