[PEAK] EventDriven configuration questions

[Phillip J. Eby]

At 11:02 AM 6/17/04 -0700, Dave Peticolas wrote:
>Is ZConfig a substitute for ini-style configuration
>in PEAK, or do they serve complementary purposes?

They're complementary.  The difference is that .ini files configure the 
environment that an application runs in, and can specify the root object of 
an application.  ZConfig files cannot define the application, but they can 
assemble an application from components.

So, .ini files define the runtime environment, ZConfig files assemble 
components.  .ini files are primarily intended for use by developers *of* 
the application, and to a limited extent for system administrators setting 
up a corporate deployment environment.  ZConfig files are primarily 
intended for users of a configurable application.  These are not fixed 
boundaries, of course, but general principles.


>Can you start an EventDriven app using an ini file?

Yes.  Just set the 'peak.running.app' property appropriately.  This could 
be done using a 'commands.Alias' or a 'naming.LinkRef' to run a separate 
ZConfig file.  Or, if you want to embed the configuration directly in the 
.ini file, it could be as simple as:

[peak.running]
app = EventDriven(
     stopAfter=5*60*60, idleTimeout=30*60,
     components=[mypkg.Part1(),mypkg.Part2(),...]
  )


>How can you configure an EventDriven app to use the
>Twisted reactor?

Add a component that depends on ITwistedReactor, and does so upon assembly, 
e.g.:


class Something(binding.Component):

     reactor = binding.Obtain(running.ITwistedReactor, uponAssembly=True)


If you add an instance of this component to your EventDriven app, it will 
then use the Twisted reactor.  Or, if you have an .ini file available, you 
can do this:

[peak.events]
isTwisted = True