[zeromq-dev] a pub with multiple subs starting sequentially

[Shaofeng Yang]

That's for one sub. Can it work with multiple subs? For example, sub1
with its IDENTITY connects to the pub and later sub2 with its identity
connects to the pub. then sub2 gets disconnected and then the pub
starts to publish data, which will be received by sub1. some time
later, sub2 re-connects to the pub. Can sub2 still receive the data
received by sub1? Actually this is my original question since my
program was written like this.

Thanks,
James


On Mon, Nov 1, 2010 at 3:49 AM, Martin Sustrik <sustrik at 250bpm.com> wrote:
> On 11/01/2010 08:46 AM, Shaofeng Yang wrote:
>>
>> Thanks for your quick response, Martin. Do you think it might make it
>> work once zmq moves to publisher side filtering. in this case, the sub
>> can register itself first and then gets disconnected. it will receive
>> the lost messages when it re-connects to the pub later. of course, it
>> will have limited queue size/time out for the subs.
>> or what's the best model/implementation for this case.
>>
>
> You can do it even now. Set the identity (ZMQ_IDENTITY) on the subscriber
> socket, then connect to the publisher. Given that the subscriber socket has
> name, publisher is able to say that a new connection being made is actually
> a reconnection and send it all the pending data. You'll never get messages
> that were sent before you connected for the first time though.
>
> Martin
>