ZeroMq IRC Log

Monday July 25, 2011

[Time] Name	Message
[13:17] hogu	Is there a way to do a pub/sub pattern but only route certain messages to certain subscribers?
[13:18] pieter_hintjens	hogu: depends on how selective you are
[13:18] pieter_hintjens	any subscriber can filter the messages it gets
[13:19] pieter_hintjens	if you want rough-grained routing you can use multiple pub sockets (i.e. break the data into streams)
[13:19] pieter_hintjens	you can also use 0MQ/3.x which does publisher-side filtering
[13:22] hogu	i definitely want the filtering to be publisher side
[13:22] hogu	i didn't realize 3.0 had that
[13:22] hogu	sounds like whati need, thank
[13:22] hogu	s
[13:26] hogu	so I'm currently doing this with websockets, a client connects, and sends authentication credentials over that socket. then I can route messages to cleints depending on their credentials. Is there a way to do that with zeromq?
[13:28] sustrik	pieter_hinjens: still want to make a video?
[13:28] hogu	specifically, i mean the ability to have multiple bi-directional channels with one bind?
[13:29] sustrik	what's so special about that?
[13:29] sustrik	even TCP gives you multiple channels per bind
[13:31] hogu	no it's not special, I'm just asking how to do that with zeromq
[13:33] sustrik	zmq_bind()
[13:33] sustrik	that's it
[13:33] hogu	REQ-REP seems close to what I want except I'd like to be able to send data to specific clients without the request
[13:34] sustrik	that's sounds more like TCP use case
[13:34] sustrik	although if you are interested there are examples of doing this using ROUTER socekts in the guide
[13:34] hogu	hm ok , let me look at that
[13:40] pieter_hintjens	sustrik: yeah, but I don't have the bandwidth right now, will work on some ideas first
[13:41] pieter_hintjens	sustrik: also I realized that if people come to 0MQ for "messaging", that's fine in fact
[13:50] sustrik	messaging?
[13:51] sustrik	like MOM?
[13:58] pieter_hintjens	yeah
[13:59] pieter_hintjens	a typical sign of confusion is "let's make an abstraction layer that hides 0MQ"
[13:59] pieter_hintjens	this is sane if you treat messaging as a generic layer
[13:59] pieter_hintjens	but 0MQ works more like a scalability design language
[14:04] sustrik	i see
[14:04] sustrik	and the conclusion is?
[14:04] pieter_hintjens	sustrik: don't know yet :-) RTFG?
[14:05] sustrik	maybe
[14:05] sustrik	i guess we don't communicate this side of the problem well yet
[14:05] sustrik	i have no idea how to do it though
[14:06] pieter_hintjens	there's a big issue with perception
[14:06] sustrik	maybe it's just matter of time
[14:06] pieter_hintjens	how people perceive communications
[14:06] pieter_hintjens	i think the shift will take time
[14:07] pieter_hintjens	it's architecture, and that takes years to learn
[14:07] sustrik	ack
[14:07] pieter_hintjens	time for a 2.1.8 and 3.0.1 IMO
[14:07] sustrik	great
[14:07] sustrik	any pending issues?
[14:07] pieter_hintjens	nope, and some nice fixes in there
[14:07] sustrik	ok
[14:08] pieter_hintjens	thursday or so, depending on the weather
[14:12] hogu	so I'm looking at the router, it looks like i have to use that with request reply patterns? can I get bi directional channels without having to adhere to teh request reply pattern?
[14:13] hogu	something like that PAIR except, with multiple connections per bind
[14:13] hogu	is this a stupid thing to want?
[14:15] sustrik	you can use ROUTER-to-ROUTER pattern
[14:15] sustrik	that way each endpoint is able to say which message goes to whom
[14:16] hogu	ah ok
[14:16] hogu	thanks
[14:17] pieter_hintjens	hogu: how much of the Guide have you read?
[14:19] hogu	the first 2 chapters
[14:19] hogu	and bit of 4
[14:19] hogu	i mean 5
[21:28] Kinbote	anyone have any luck building openpgm and linking zmq to it?
[21:28] Kinbote	i'm trying to use epgm
[21:29] Kinbote	i install zmq from source, passing --with-pgm to configure, and it install fine, apparently it downloads and builds openpgm in ./build, but when i try to connect to an epgm socket from code i get this error Assertion failed: rc == 0 (connect_session.cpp:84)
[21:50] dontfudge	I'm looking to use epgm in ZMQ. the man page installed give an example of the connect address, but not the bind address. Are they supposed to be the same?
[21:56] samBiotic	dontfudge, using pub/sub yes i believe