[Twisted-Python] Logging observers and threads

[Itamar Turner-Trauring]

On 07/12/2012 05:17 AM, Tristan Seligmann wrote:
> 3) log observers should expect to be inovked in non-reactor threads,
> making this a Mantissa bug.
>
In theory this is the case - the logging howto says "The observer needs 
to be thread safe if you anticipate using threads in your program." The 
API docs don't mention threads, though..

In practice however, probably every custom observer gets this wrong, so 
we really need some infrastructure to make this easier or to fix it. 
Possibly we should have some way to indicate an observer is thread-safe, 
assume by default they are not, and if they are not wrap them in a 
reactor.callFromThread wrapper.

I would also like some infrastructure to make the file log observer run 
in its own thread, but that's almost the opposite use case :)

-Itamar