bmcweb logging

[Ed Tanous]

On Thu, Oct 29, 2020 at 8:47 AM Ratan Gupta <ratagupt at linux.vnet.ibm.com> wrote:
>
> Hi Ed,
>
> I was having issues in getting the logs from bmcweb repo, If I don't
> define the compiler flag(BMCWEB_ENABLE_LOGGING) then it doesn't get me
> any logs in journal(not even error log) and if I define the compiler
> flag then it gets too much debug info.

What's your limit for "too much"?

>
> Seems it happens because we have hardcoded the logelevel  and there is
> no way through which we can change except making the change manually in
> the following place.
>
> https://github.com/openbmc/bmcweb/blob/master/http/logging.hpp#L93
>
> Suggestion is we can define another compile time flag for log level and
> use that log level at the above line for type of logging , by default
> logging should be enabled with error log level.

Thusfar, we don't really have a definition of what kind of detail
should be included at each log level, nor are we consistent about
setting the log levels.  If it's important to you, and you want to put
together some patches, we certainly could define the log verbosity,
but we'd also have to come up with better definitions for what level
each log needs to take, and be more consistent about it.

IMO, that level of log granularity was never that valuable to debug,
my thought being that if I'm enabling logging I don't care about
performance, so the more logs the better.  When reproducing a failure,
there doesn't tend to be a lot of logging present, and it's easy
enough to find what you want, but maybe you had a different
experience?

Long term, my intent was to just get rid of the various verbosities,
and make logging ON or OFF in the code, and downgrade to a single
macro, but if you see a need, we could certainly go the other
direction.

>
> If there is a need user can play with new compiler flag for more verbose
> logging.

I don't personally see the need, but if it would help you, I don't
think it adds much complexity to do it, and I'd be happy to review
your patches.

>
> Am I missing something in usage of logging infra?
>
> Ratan
>
>


Just to be clear, you're using logging in a debug context, correct?
If we're trying to use this to define an access log, that's a very
different problem space, and the existing logging infrastructure would
be poorly suited for it.