Description Dirk Wiesenthal 2013-02-01 20:01:37 CET

Created attachment 5034 [details]
Proof of concept for a threading decorator

At the moment, adding a "non-blocking" function to a module is quite painful.
It is often done this way:

def nonblock(self, request):
  var1 = request.options.get('var1')
  self.finished(request.id, var1 * 2)
  def _thread(var):
    do_some_expensive_stuff(var)
  def _finished(thread, result):
    if isinstance(result, BaseException):
      MODULE.warn('Exception during expensive: %s' % (str(result))
  thread = notifier.threads.Simple('nonblock', notifier.Callback(_thread,
var1), _finished)
  thread.run()

In UCS 3.1 we have added a decorator for simple tasks (@simple_response), but
it is limited when it comes to background tasks that should not block the whole
module. We should extend its function to be able to spawn a thread after
sending a response easily.

Idea:

@simple_response
def nonblock(self, var1):
  yield var1 * 2
  do_some_expensive_stuff(var1)

Proof of concept attached (does not work very well together with @log at the
moment). Used App Center for demonstration.

The function could be helpful in a couple of modules (requiring nonblocking
actions was the #1 show stopper to use @simple_response at a larger scale). I
have been working on one third-party module and this could have used it, too.