[zeromq-dev] Logging format for sys://log transport

[Martin Sustrik]

Oliver,

> Martin Sustrik said the following on 11/19/2010 4:55 AM:
>> I think there are many possible audiences, however, we haven't yet
>> figured out who exactly is it going to be.
>>
>> Thus, the whole system should be open-ended allowing for later addition
>> of functionality. That's why I alluded to /proc pseudofilesystem.
> I would caution against this approach. If you try to please everyone,
> you will require a great deal of description for each log message. The
> logging requirements from a developer are likely to be different than
> those of a sysadmin or a debugger or a user, both of whom are going to
> want different ways of artefacting any given log message.
>
> Here is my $0.02. More than anything else, make the ZeroMQ logging
> assist with developing a ZeroMQ tool, and leave the downstream reportage
> to the application developer.
>
> It wants to provide a way for the ZeroMQ team *and* the application
> developer to locate a point of failure in the ZeroMQ source, and having
> a logging entry with the file/line of the report is somehow mentally
> more conducive to your going and looking at that piece of code than some
> random message (after a few years of working with other people's code,
> you rapidly learn that searching for any given text string in
> someone-elses-code is going to be the start of a really lousy day).
>
> The temptation to develop a new logging system will be strong. I'm
> pretting sure that logging leads directly to suffering without the
> intermediate steps of fear, anger and hate :)

I think you've misunderstood. The logging system is not meant to be used 
for debugging 0MQ source code. Instead it is meant for debugging the 
topology.

Some possible examples of log messages:

- particular endpoint uses invalid wire-level protocol
- particular endpoint is not accessible for a prolonged period of time
- there's a cycle in the topology
- etc.

Martin