Re: spawning a xvfb and firefox with a timeout

Hi Jean-Paul,

decorated with inlineCallbacks? why would I need that?

I'm trying to figure that out... but would it look like this?

        def killProcessIfAlive(self):
                logging.debug("killProcessIfAlive called")
                @defer.inlineCallbacks
                try:
                        yield self.transport.signalProcess('KILL')
                except error.ProcessExitedAlready:
                        logging.debug("process already exited")
                        pass

        def connectionMade(self):
                logging.debug("connection made timeout = %d", self.timeout)
                #@defer.inlineCallbacks
                def onTimer():
                        logging.debug("timeout triggered")
                        self.killProcessIfAlive()
                d = reactor.callLater(self.timeout, onTimer)


----
also I tried before you had sent out the email

os.kill(self.pid, SIGTERM)
and
os.kill(self.pid, SIGTERM)

but not

os.kill(-process.transport.pid, SIGTERM) (with the dash, does that
make a difference?)
On Mon, Aug 22, 2011 at 12:53 PM,  <[email protected]> wrote:
> On 04:32 pm, [email protected] wrote:
>>I think I might have figured out that you have to add usePTY=1 to
>>associate the process group, so that the children will be killed when
>>the parent process is killed.
>>e.g.
>>subprocess = reactor.spawnProcess(self.pp, args[0], args, env = os.e
>>nviron, usePTY=1)
>
> This is a not bad approach.  Another possibility might be to leave
> usePTY out but change how you kill the process.  There is the notion of
> "process groups", which contain one or more processes, and all of the
> processes in a group can be sent a signal by passing a negative number
> to os.kill.  For your case, the process group would probably be the same
> as the pid of the xvfb-run process, so you could do something like:
>
>    os.kill(-process.transport.pid, SIGTERM)
>
> Whether this is better or worse than using a PTY depends on the
> particulars of how xvfb-run manages its child process, whether it is
> okay to actually have a pty allocated, and probably some other POSIX
> arcana.
>>but I tried to separate out the killing in another process and now the
>>new method isnt' called.
>>are ProcessProtocol classes allowed to have other methods added to it
>>for calling?
>>
>>45     def killProcessIfAlive(self):
>>46         logging.debug("killProcessIfAlive called")
>>47         try:
>>48             yield self.transport.signalProcess('KILL')
>>49         except error.ProcessExitedAlready:
>>50             logging.debug("process already exited")
>>51             pass
>
> It looks like you wanted killProcessIfAlive to be decorated with
> inlineCallbacks, but I don't see that here.  So that would prevent the
> signal from ever actually being sent.  signalProcess doesn't return a
> Deferred though, so you can skip inlineCallbacks and the yield and that
> should also fix the problem.
>>52
>>53     def connectionMade(self):
>>54         logging.debug("connection made timeout = %d", self.timeout)
>>55         @defer.inlineCallbacks
>>56         def onTimer():
>>57             logging.debug("timeout triggered")
>>58             self.killProcessIfAlive()
>>59         d = reactor.callLater(self.timeout, onTimer)
>
> Ah, there's the inlineCallbacks.  It won't work there, though, it needs
> to go onto the generator function (the function that has yield in it).
>
> Jean-Paul
>
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