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Jonathan H

2017-Jun-30 21:23 UTC

[asterisk-users] Simplest way of executing a non-blocking (async) python AGI script?

OK, I give up and come grovelling, "Fork" was suggested at 18:23,
it's
now 22:20 and I have been through 4 different methods, all block with
a 2 second delay before returning to dialplan.

Here are just some of the examples I have tried, as as per the
suggestions, I am closing all possible outputs in the forked process.

https://docs.python.org/3.5/library/multiprocessing.html
https://docs.python.org/3.5/library/multiprocessing.html?highlight=multiprocessing#multiprocessing.Process.join
https://stackoverflow.com/questions/19747371/python-exit-commands-why-so-many-and-when-should-each-be-used
https://stackoverflow.com/questions/27624850/launch-a-completely-independent-process
https://stackoverflow.com/questions/13612434/why-are-the-methods-sys-exit-exit-raise-systemexit-not-working
https://stackoverflow.com/questions/43280947/os-fork-share-local-variable-with-parent
https://stackoverflow.com/questions/24052217/may-someone-explain-the-following-os-fork-example-to-me
http://www.python-course.eu/forking.php
https://pymotw.com/3/subprocess/
http://code.activestate.com/recipes/186101-really-closing-stdin-stdout-stderr/

This is the most likely looking code based on the examples. I would
really, really appreciate a couple of pointers as to where I might be
going wrong:

#! /usr/bin/env python3
# -*- coding: utf-8 -*-

import multiprocessing as mp
import time
import sys
import os

#from asterisk.agi import AGI
#agi = AGI()

def f(name):
    sys.stdin.close()
    sys.stdout.close()
    sys.stderr.close()
    os.close(0)   # close C's stdin stream
    os.close(1)   # close C's stdout stream
    os.close(2)   # close C's stderr stream
    time.sleep(2)
    f = open('/var/lib/asterisk/agi-bin/tns/testing/testout.txt',
'w')
    f.write(name)
    f.close()


if __name__ == '__main__':
    print('before process')
    mp.set_start_method('fork')
    q = mp.Queue()
    p = mp.Process(target=f, args=('asterisk',))
    p.start()
    sys.exit()

On 30 June 2017 at 19:59, J Montoya or A J Stiles
<asterisk_list at earthshod.co.uk> wrote:> On Friday 30 Jun 2017, Jonathan H wrote:
>> What's the simplest, easiest quickest least-code way of firing off
an AGI
>> with some variable, and then returning to the dialplan?
>
> You have to use the "fork" command.  This starts a copy of the
process with
> all the same internal state including variables and filehandles.  The
command
> returns a non-zero value  (which is the PID of the child process; you may
need
> this, if you plan to outlive your children and have to clear their entries
> from the process table)  to the parent process, and zero to the child
process.
> So in the parent, you exit and return to the dialplan; and in the child,
you
> close STDIN, STDOUT and STDERR  (so no process is waiting for you to
produce
> output),  then just take your time doing what you have to.  The parent is
> already long dead by this time, so exiting goes nowhere.
>
>> I've seen people talking about fastAGI, stasis, python ASYNC... all
seems
>> rather complicated. I feel I must be missing something embarrassingly
>> obvious - isn't there just the equivalent of the unix shell's
"&"?!
>
> Yes, fork!  That is what the "&" operator is using
"under the bonnet".
>
> --
> JKLM
>
> Note:  Originating address only accepts e-mail from list!  If replying off-
> list, change address to asterisk1list at earthshod dot co dot uk .
>
> --
> _____________________________________________________________________
> -- Bandwidth and Colocation Provided by http://www.api-digital.com --
>
> Check out the new Asterisk community forum at:
https://community.asterisk.org/
>
> New to Asterisk? Start here:
>       https://wiki.asterisk.org/wiki/display/AST/Getting+Started
>
> asterisk-users mailing list
> To UNSUBSCRIBE or update options visit:
>    http://lists.digium.com/mailman/listinfo/asterisk-users

Marcelo Terres

2017-Jun-30 22:18 UTC

head link

[asterisk-users] Simplest way of executing a non-blocking (async) python AGI script?

Take a look on that:

https://issues.asterisk.org/jira/browse/ASTERISK-20532

Regards,
Marcelo H. Terres <mhterres at gmail.com>
IM: mhterres at jabber.mundoopensource.com.br
https://www.mundoopensource.com.br
https://twitter.com/mhterres
https://linkedin.com/in/marceloterres


On 30 June 2017 at 22:23, Jonathan H <lardconcepts at gmail.com>
wrote:> OK, I give up and come grovelling, "Fork" was suggested at 18:23,
it's
> now 22:20 and I have been through 4 different methods, all block with
> a 2 second delay before returning to dialplan.
>
> Here are just some of the examples I have tried, as as per the
> suggestions, I am closing all possible outputs in the forked process.
>
> https://docs.python.org/3.5/library/multiprocessing.html
>
https://docs.python.org/3.5/library/multiprocessing.html?highlight=multiprocessing#multiprocessing.Process.join
>
https://stackoverflow.com/questions/19747371/python-exit-commands-why-so-many-and-when-should-each-be-used
>
https://stackoverflow.com/questions/27624850/launch-a-completely-independent-process
>
https://stackoverflow.com/questions/13612434/why-are-the-methods-sys-exit-exit-raise-systemexit-not-working
>
https://stackoverflow.com/questions/43280947/os-fork-share-local-variable-with-parent
>
https://stackoverflow.com/questions/24052217/may-someone-explain-the-following-os-fork-example-to-me
> http://www.python-course.eu/forking.php
> https://pymotw.com/3/subprocess/
>
http://code.activestate.com/recipes/186101-really-closing-stdin-stdout-stderr/
>
> This is the most likely looking code based on the examples. I would
> really, really appreciate a couple of pointers as to where I might be
> going wrong:
>
> #! /usr/bin/env python3
> # -*- coding: utf-8 -*-
>
> import multiprocessing as mp
> import time
> import sys
> import os
>
> #from asterisk.agi import AGI
> #agi = AGI()
>
> def f(name):
>     sys.stdin.close()
>     sys.stdout.close()
>     sys.stderr.close()
>     os.close(0)   # close C's stdin stream
>     os.close(1)   # close C's stdout stream
>     os.close(2)   # close C's stderr stream
>     time.sleep(2)
>     f = open('/var/lib/asterisk/agi-bin/tns/testing/testout.txt',
'w')
>     f.write(name)
>     f.close()
>
>
> if __name__ == '__main__':
>     print('before process')
>     mp.set_start_method('fork')
>     q = mp.Queue()
>     p = mp.Process(target=f, args=('asterisk',))
>     p.start()
>     sys.exit()
>
> On 30 June 2017 at 19:59, J Montoya or A J Stiles
> <asterisk_list at earthshod.co.uk> wrote:
>> On Friday 30 Jun 2017, Jonathan H wrote:
>>> What's the simplest, easiest quickest least-code way of firing
off an AGI
>>> with some variable, and then returning to the dialplan?
>>
>> You have to use the "fork" command.  This starts a copy of
the process with
>> all the same internal state including variables and filehandles.  The
command
>> returns a non-zero value  (which is the PID of the child process; you
may need
>> this, if you plan to outlive your children and have to clear their
entries
>> from the process table)  to the parent process, and zero to the child
process.
>> So in the parent, you exit and return to the dialplan; and in the
child, you
>> close STDIN, STDOUT and STDERR  (so no process is waiting for you to
produce
>> output),  then just take your time doing what you have to.  The parent
is
>> already long dead by this time, so exiting goes nowhere.
>>
>>> I've seen people talking about fastAGI, stasis, python ASYNC...
all seems
>>> rather complicated. I feel I must be missing something
embarrassingly
>>> obvious - isn't there just the equivalent of the unix
shell's "&"?!
>>
>> Yes, fork!  That is what the "&" operator is using
"under the bonnet".
>>
>> --
>> JKLM
>>
>> Note:  Originating address only accepts e-mail from list!  If replying
off-
>> list, change address to asterisk1list at earthshod dot co dot uk .
>>
>> --
>> _____________________________________________________________________
>> -- Bandwidth and Colocation Provided by http://www.api-digital.com --
>>
>> Check out the new Asterisk community forum at:
https://community.asterisk.org/
>>
>> New to Asterisk? Start here:
>>       https://wiki.asterisk.org/wiki/display/AST/Getting+Started
>>
>> asterisk-users mailing list
>> To UNSUBSCRIBE or update options visit:
>>    http://lists.digium.com/mailman/listinfo/asterisk-users
>
> --
> _____________________________________________________________________
> -- Bandwidth and Colocation Provided by http://www.api-digital.com --
>
> Check out the new Asterisk community forum at:
https://community.asterisk.org/
>
> New to Asterisk? Start here:
>       https://wiki.asterisk.org/wiki/display/AST/Getting+Started
>
> asterisk-users mailing list
> To UNSUBSCRIBE or update options visit:
>    http://lists.digium.com/mailman/listinfo/asterisk-users

Jonathan H

2017-Jul-01 07:12 UTC

head link

[asterisk-users] Simplest way of executing a non-blocking (async) python AGI script?

Oh wow - thank you SO much Marcelo.

This works perfectly - exactly as I wanted. Don't think I'd have
figured it out, though.

Well, that ticket says "not a bug" if this isn't a bug, then
"behaviour which differs dramatically from that which is expected"
would definitely be the tag.

Again, this fix works, and thank you!



On 30 June 2017 at 23:18, Marcelo Terres <mhterres at gmail.com>
wrote:> Take a look on that:
>
> https://issues.asterisk.org/jira/browse/ASTERISK-20532
>
> Regards,
> Marcelo H. Terres <mhterres at gmail.com>
> IM: mhterres at jabber.mundoopensource.com.br
> https://www.mundoopensource.com.br
> https://twitter.com/mhterres
> https://linkedin.com/in/marceloterres
>
>
> On 30 June 2017 at 22:23, Jonathan H <lardconcepts at gmail.com>
wrote:
>> OK, I give up and come grovelling, "Fork" was suggested at
18:23, it's
>> now 22:20 and I have been through 4 different methods, all block with
>> a 2 second delay before returning to dialplan.
>>
>> Here are just some of the examples I have tried, as as per the
>> suggestions, I am closing all possible outputs in the forked process.
>>
>> https://docs.python.org/3.5/library/multiprocessing.html
>>
https://docs.python.org/3.5/library/multiprocessing.html?highlight=multiprocessing#multiprocessing.Process.join
>>
https://stackoverflow.com/questions/19747371/python-exit-commands-why-so-many-and-when-should-each-be-used
>>
https://stackoverflow.com/questions/27624850/launch-a-completely-independent-process
>>
https://stackoverflow.com/questions/13612434/why-are-the-methods-sys-exit-exit-raise-systemexit-not-working
>>
https://stackoverflow.com/questions/43280947/os-fork-share-local-variable-with-parent
>>
https://stackoverflow.com/questions/24052217/may-someone-explain-the-following-os-fork-example-to-me
>> http://www.python-course.eu/forking.php
>> https://pymotw.com/3/subprocess/
>>
http://code.activestate.com/recipes/186101-really-closing-stdin-stdout-stderr/
>>
>> This is the most likely looking code based on the examples. I would
>> really, really appreciate a couple of pointers as to where I might be
>> going wrong:
>>
>> #! /usr/bin/env python3
>> # -*- coding: utf-8 -*-
>>
>> import multiprocessing as mp
>> import time
>> import sys
>> import os
>>
>> #from asterisk.agi import AGI
>> #agi = AGI()
>>
>> def f(name):
>>     sys.stdin.close()
>>     sys.stdout.close()
>>     sys.stderr.close()
>>     os.close(0)   # close C's stdin stream
>>     os.close(1)   # close C's stdout stream
>>     os.close(2)   # close C's stderr stream
>>     time.sleep(2)
>>     f =
open('/var/lib/asterisk/agi-bin/tns/testing/testout.txt', 'w')
>>     f.write(name)
>>     f.close()
>>
>>
>> if __name__ == '__main__':
>>     print('before process')
>>     mp.set_start_method('fork')
>>     q = mp.Queue()
>>     p = mp.Process(target=f, args=('asterisk',))
>>     p.start()
>>     sys.exit()
>>
>> On 30 June 2017 at 19:59, J Montoya or A J Stiles
>> <asterisk_list at earthshod.co.uk> wrote:
>>> On Friday 30 Jun 2017, Jonathan H wrote:
>>>> What's the simplest, easiest quickest least-code way of
firing off an AGI
>>>> with some variable, and then returning to the dialplan?
>>>
>>> You have to use the "fork" command.  This starts a copy
of the process with
>>> all the same internal state including variables and filehandles. 
The command
>>> returns a non-zero value  (which is the PID of the child process;
you may need
>>> this, if you plan to outlive your children and have to clear their
entries
>>> from the process table)  to the parent process, and zero to the
child process.
>>> So in the parent, you exit and return to the dialplan; and in the
child, you
>>> close STDIN, STDOUT and STDERR  (so no process is waiting for you
to produce
>>> output),  then just take your time doing what you have to.  The
parent is
>>> already long dead by this time, so exiting goes nowhere.
>>>
>>>> I've seen people talking about fastAGI, stasis, python
ASYNC... all seems
>>>> rather complicated. I feel I must be missing something
embarrassingly
>>>> obvious - isn't there just the equivalent of the unix
shell's "&"?!
>>>
>>> Yes, fork!  That is what the "&" operator is using
"under the bonnet".
>>>
>>> --
>>> JKLM
>>>
>>> Note:  Originating address only accepts e-mail from list!  If
replying off-
>>> list, change address to asterisk1list at earthshod dot co dot uk .
>>>
>>> --
>>>
_____________________________________________________________________
>>> -- Bandwidth and Colocation Provided by http://www.api-digital.com
--
>>>
>>> Check out the new Asterisk community forum at:
https://community.asterisk.org/
>>>
>>> New to Asterisk? Start here:
>>>       https://wiki.asterisk.org/wiki/display/AST/Getting+Started
>>>
>>> asterisk-users mailing list
>>> To UNSUBSCRIBE or update options visit:
>>>    http://lists.digium.com/mailman/listinfo/asterisk-users
>>
>> --
>> _____________________________________________________________________
>> -- Bandwidth and Colocation Provided by http://www.api-digital.com --
>>
>> Check out the new Asterisk community forum at:
https://community.asterisk.org/
>>
>> New to Asterisk? Start here:
>>       https://wiki.asterisk.org/wiki/display/AST/Getting+Started
>>
>> asterisk-users mailing list
>> To UNSUBSCRIBE or update options visit:
>>    http://lists.digium.com/mailman/listinfo/asterisk-users
>
> --
> _____________________________________________________________________
> -- Bandwidth and Colocation Provided by http://www.api-digital.com --
>
> Check out the new Asterisk community forum at:
https://community.asterisk.org/
>
> New to Asterisk? Start here:
>       https://wiki.asterisk.org/wiki/display/AST/Getting+Started
>
> asterisk-users mailing list
> To UNSUBSCRIBE or update options visit:
>    http://lists.digium.com/mailman/listinfo/asterisk-users

asterisk users - Jun 2017 - Simplest way of executing a non-blocking (async) python AGI script?

[asterisk-users] Simplest way of executing a non-blocking (async) python AGI script?

[asterisk-users] Simplest way of executing a non-blocking (async) python AGI script?

[asterisk-users] Simplest way of executing a non-blocking (async) python AGI script?