Re: GJS: Logging for extensions?

[Tim Cuthbertson <tim gfxmonk net>]

On Sun, Jul 3, 2011 at 5:17 PM, Jasper St. Pierre <jstpierre mecheye net> wrote:
> On Sun, Jul 3, 2011 at 2:25 AM, Tim Cuthbertson <tim gfxmonk net> wrote:
>> Hi all,
>>
>> Since I'm working on a reasonably complex shell extension
>> (http://gfxmonk.net/shellshape/), I am wondering if there's a decent
>> logging system for gjs or gnome-shell. Right now I'm using
>> global.log(), but this is a bit rubbish since it's really verbose, and
>> I end up leaving my log comments commented out and traipsing round the
>> codebase enabling them when I'm trying to debug something.
>>
>> So, is there anything for this already? Or should I try porting a
>> browser-based logger to gjs and/or roll my own?
>
> What would you like? Something like "console.log", "console.warn" and
> "console.error"? Where would you like it to go?
>
> I've been trying to get it out of the LookingGlass for a bit now, but
> I don't have any good ideas for replacements besides stderr or a new a
> panel. What would you like?
>
>> Cheers,
>>  - Tim.


I'm thinking something like log4j, python's logging module, etc.
Basically, I'd like:
 - namespaced loggers via getLogger("namespace") with individual log levels
 - a way to configure log levels per-logger, either programatically or
with environment variables (or better: both)
 - logger heirarchicy (e.g logger "shellshape.layout" inherits its log
level from the "shellshape" logger unless its level is specifically
changed)

That all relates to the programming interface, not where logs go.
Right now all I need is to log to the console, I just want a better
way to manage *what* goes to the console.

But it would be good to have gnome-shell / gjs specific appenders. E.g
the default appender would pump messages out to the console, but you
could add/configure additional appenders, like:
 - file output (I'd love to be able to ask my users to send me
/var/log/shellshape for bug reports)
 - syslog
 - an actual notification popup (only for really critical ones, presumably)

These could have different formatters, so that the console is short
and easily readable but the full information (logger name, timestamp)
could be written to the log file or syslog.

I've had a look at log4javascript: http://log4javascript.org/
It looks pretty decent, I think I'll see if I can get it outputting to
the gjs console. Do you know if/how I could:
 - get access to system environment variables, and
 - open / append to a file on disk

I don't know much about gjs system integration, and docs seem
exceedingly scarce...

Cheers,
 - Tim.