[zeromq-dev] XSUB/XPUB upstream messages

[Pieter Hintjens]

So the use case is re-broadcasting messages from subscribers; it's
kind of nice, and may simplify some patterns.

Gets my vote. :-)
-Pieter

On Mon, Dec 31, 2012 at 5:19 PM, John Muehlhausen <jgm at jgm.org> wrote:
> To my knowledge, I have not used a sub with many pub connections, but I
> assume that any subscription messages are copied to all of them.  If that is
> the case, then these upstream messages (that are not subscription related)
> would seem to be copied to all as well, unless pains were taken to do
> something different.
>
> As for a use-case, this one is contrived because I'm not sure that I am free
> to talk about the real one.  Imagine a chat system where every subscriber is
> interested in a some or all of the messages, and where every subscriber can
> generate messages.  The new functionality could be used to get a new message
> generated by a particular subscriber all the way back to the root publisher
> (perhaps there are routing nodes) where it is then published to all who are
> subscribing, perhaps with modifications (e.g., from a moderator).
>
> Without the modification there seem to be two approaches:
> - use another socket, which doesn't seem ideal since we already have one
> with upstream capability
> - package the upstream "message" as a sub/unsub pair... I actually tried
> this and the trie gets unwieldy above around 7000 bytes, particularly with
> stack usage in the recursive trie routines
>
> -John
>
> On Mon, Dec 31, 2012 at 10:06 AM, Pieter Hintjens <ph at imatix.com> wrote:
>>
>> On Sun, Dec 30, 2012 at 7:13 PM, John Muehlhausen <jgm at jgm.org> wrote:
>>
>> > Currently XSUB will not send messages unless they contain a subscribe or
>> > unsubscribe prefix (see code fragment below).
>> >
>> > It would be useful to pass these "malformed" messages anyway, although
>> > they
>> > would not affect subscription status.
>>
>> It's an interesting proposal, but what specific use cases do you have?
>>
>> Would you round-robin if the sub has many pub connections, or would
>> you copy to all connections?
>>
>> -Pieter
>>
>> _______________________________________________
>> zeromq-dev mailing list
>> zeromq-dev at lists.zeromq.org
>> http://lists.zeromq.org/mailman/listinfo/zeromq-dev
>
>
>
> _______________________________________________
> zeromq-dev mailing list
> zeromq-dev at lists.zeromq.org
> http://lists.zeromq.org/mailman/listinfo/zeromq-dev
>