SimpleXMLRPCServer interruptable?

[Bret]

I'm coming back to Python after an absence and it's surprising how
many things I've forgotten since wandering (against my will) into Java
land.

Anyway, I have a need for a way to make SimpleXMLRPCSer ver
interruptable. Basically, I have a main server that, in response to
certain RPC calls, creates additional servers on different ports. I
then need to be able to shut these additional servers down.

I've got something like this in the __init__ of the class which
contains the spawned servers:

def __init__(self, host, port):
:
:
server = SimpleXMLRPCSer ver((host, port))
:
: Bunch of server.register _function calls
:
def serverWrapper() :
try:
while True:
server.handle_r equest()
except:
pass

One of the methods that I register is:

def shutdown(self):
raise "Quitting time"

Through watching logs and such I can see that the shutdown() method is
getting called, but the loop isn't getting broken. I've done
something like this before in a previous job (so I don't have my
source in front of me, more's the pity) and am hoping someone can
chime in with a good idea.

Thanks in advance!


Bret Wortman

[Bret]

Re: SimpleXMLRPCSer ver interruptable?

I just tried changing this so that I now have a threading.Event ()
called self.done, which is set within the body of the shutdown()
method. The serverWrapper loop now looks like this:

def serverWrapper() :
while True:
server.handle_r equest()
if self.done.isSet ():
break

This works, but only if I follow the shutdown() rpc call a few seconds
later with ... something else to cause handle_request( ) to complete
again. Obviously, not quite the right approach....


On Dec 5, 2:00 pm, Bret <bret.wort...@g mail.comwrote:

I'm coming back to Python after an absence and it's surprising how
many things I've forgotten since wandering (against my will) into Java
land.
>
Anyway, I have a need for a way to make SimpleXMLRPCSer ver
interruptable. Basically, I have a main server that, in response to
certain RPC calls, creates additional servers on different ports. I
then need to be able to shut these additional servers down.
>
I've got something like this in the __init__ of the class which
contains the spawned servers:
>
def __init__(self, host, port):
:
:
server = SimpleXMLRPCSer ver((host, port))
:
: Bunch of server.register _function calls
:
def serverWrapper() :
try:
while True:
server.handle_r equest()
except:
pass
>
One of the methods that I register is:
>
def shutdown(self):
raise "Quitting time"
>
Through watching logs and such I can see that the shutdown() method is
getting called, but the loop isn't getting broken. I've done
something like this before in a previous job (so I don't have my
source in front of me, more's the pity) and am hoping someone can
chime in with a good idea.
>
Thanks in advance!
>
Bret Wortman

[Gabriel Genellina]

Re: SimpleXMLRPCSer ver interruptable?

En Wed, 05 Dec 2007 18:20:35 -0300, Bret <bret.wortman@g mail.comescribi ó:

I just tried changing this so that I now have a threading.Event ()
called self.done, which is set within the body of the shutdown()
method. The serverWrapper loop now looks like this:
>
def serverWrapper() :
while True:
server.handle_r equest()
if self.done.isSet ():
break
>
This works, but only if I follow the shutdown() rpc call a few seconds
later with ... something else to cause handle_request( ) to complete
again. Obviously, not quite the right approach....

You could try setting a reasonable timeout on the listening socket; I
would override the server_bind method, calling self.socket.set timeout(xxx)
before calling the inherited method. I've never actually done it with a
SimpleXMLRPCSer ver, but *should* work. Don't use a very small timeout,
because it affects *all* subsequent operations.

--
Gabriel Genellina

[Edward Kozlowski]

Re: SimpleXMLRPCSer ver interruptable?

On Dec 5, 6:22 pm, "Gabriel Genellina" <gagsl-...@yahoo.com.a rwrote:

En Wed, 05 Dec 2007 18:20:35 -0300, Bret <bret.wort...@g mail.comescribi ó:
>

I just tried changing this so that I now have a threading.Event ()
called self.done, which is set within the body of the shutdown()
method. The serverWrapper loop now looks like this:

>

def serverWrapper() :
while True:
server.handle_r equest()
if self.done.isSet ():
break

>

This works, but only if I follow the shutdown() rpc call a few seconds
later with ... something else to cause handle_request( ) to complete
again. Obviously, not quite the right approach....

>
You could try setting a reasonable timeout on the listening socket; I
would override the server_bind method, calling self.socket.set timeout(xxx)
before calling the inherited method. I've never actually done it with a
SimpleXMLRPCSer ver, but *should* work. Don't use a very small timeout,
because it affects *all* subsequent operations.
>
--
Gabriel Genellina

Try this:

def __init__(self, host, port):
self.done = False
server = SimpleXMLRPCSer ver((host, port))
:
: Bunch of server.register _function calls
:
def serverWrapper() :
try:
while not self.done:
server.handle_r equest()
except:
pass

Your shutdown method becomes:

def shutdown(self):
self.done = True

HTH

-Edward Kozlowski

[Edward Kozlowski]

Re: SimpleXMLRPCSer ver interruptable?

On Dec 5, 10:19 pm, Edward Kozlowski <ekozlows...@gm ail.comwrote:

On Dec 5, 6:22 pm, "Gabriel Genellina" <gagsl-...@yahoo.com.a rwrote:
>
>
>

En Wed, 05 Dec 2007 18:20:35 -0300, Bret <bret.wort...@g mail.comescribi ó:

>

I just tried changing this so that I now have a threading.Event ()
called self.done, which is set within the body of the shutdown()
method. The serverWrapper loop now looks like this:

>

def serverWrapper() :
while True:
server.handle_r equest()
if self.done.isSet ():
break

>

This works, but only if I follow the shutdown() rpc call a few seconds
later with ... something else to cause handle_request( ) to complete
again. Obviously, not quite the right approach....

>

You could try setting a reasonable timeout on the listening socket; I
would override the server_bind method, calling self.socket.set timeout(xxx)
before calling the inherited method. I've never actually done it with a
SimpleXMLRPCSer ver, but *should* work. Don't use a very small timeout,
because it affects *all* subsequent operations.

>

--
Gabriel Genellina

>
Try this:
>
def __init__(self, host, port):
self.done = False
server = SimpleXMLRPCSer ver((host, port))
:
: Bunch of server.register _function calls
:
def serverWrapper() :
try:
while not self.done:
server.handle_r equest()
except:
pass
>
Your shutdown method becomes:
>
def shutdown(self):
self.done = True
>
HTH
>
-Edward Kozlowski

Sorry about the first post, I shot from the hip and had to make a few
more modifications to make it 'working' code. The example below works
fine for me.

import SimpleXMLRPCSer ver

class myServer:
def __init__(self, host, port):
self.done = False
self.server = SimpleXMLRPCSer ver.SimpleXMLRP CServer((host,
port))

def shutdown(self):
self.done = True
return 0

def getName(self):
return "Hey, I'm Ed"

def serverWrapper(s elf):
self.server.reg ister_function( self.getName)
self.server.reg ister_function( self.shutdown)
try:
while not self.done:
self.server.han dle_request()
except:
pass


if __name__ == "__main__":
myServer('local host', 6058).serverWra pper()

----

>>s.getName()

"Hey, I'm Ed"

>>s.shutdown( )

0

[Bret]

Re: SimpleXMLRPCSer ver interruptable?

On Dec 5, 10:00 pm, Edward Kozlowski <ekozlows...@gm ail.comwrote:

On Dec 5, 10:19 pm, Edward Kozlowski <ekozlows...@gm ail.comwrote:
>
>
>

On Dec 5, 6:22 pm, "Gabriel Genellina" <gagsl-...@yahoo.com.a rwrote:

>

En Wed, 05 Dec 2007 18:20:35 -0300, Bret <bret.wort...@g mail.comescribi ó:

>

I just tried changing this so that I now have a threading.Event ()
called self.done, which is set within the body of the shutdown()
method. The serverWrapper loop now looks like this:

>

def serverWrapper() :
while True:
server.handle_r equest()
if self.done.isSet ():
break

>

This works, but only if I follow the shutdown() rpc call a few seconds
later with ... something else to cause handle_request( ) to complete
again. Obviously, not quite the right approach....

>

You could try setting a reasonable timeout on the listening socket; I
would override the server_bind method, calling self.socket.set timeout(xxx)
before calling the inherited method. I've never actually done it with a
SimpleXMLRPCSer ver, but *should* work. Don't use a very small timeout,
because it affects *all* subsequent operations.

>

--
Gabriel Genellina

>

Try this:

>

def __init__(self, host, port):
self.done = False
server = SimpleXMLRPCSer ver((host, port))
:
: Bunch of server.register _function calls
:
def serverWrapper() :
try:
while not self.done:
server.handle_r equest()
except:
pass

>

Your shutdown method becomes:

>

def shutdown(self):
self.done = True

>

HTH

>

-Edward Kozlowski

>
Sorry about the first post, I shot from the hip and had to make a few
more modifications to make it 'working' code. The example below works
fine for me.
>
import SimpleXMLRPCSer ver
>
class myServer:
def __init__(self, host, port):
self.done = False
self.server = SimpleXMLRPCSer ver.SimpleXMLRP CServer((host,
port))
>
def shutdown(self):
self.done = True
return 0
>
def getName(self):
return "Hey, I'm Ed"
>
def serverWrapper(s elf):
self.server.reg ister_function( self.getName)
self.server.reg ister_function( self.shutdown)
try:
while not self.done:
self.server.han dle_request()
except:
pass
>
if __name__ == "__main__":
myServer('local host', 6058).serverWra pper()
>
---->>s.getName()
"Hey, I'm Ed"

>s.shutdown()

>
0

Thanks to all! I'm now keeping a file of my own snippets in hardcopy
so I won't lose them next time I change jobs. :-)


Bret

[Bret]

Re: SimpleXMLRPCSer ver interruptable?

On Dec 6, 7:04 am, Bret <bret.wort...@g mail.comwrote:

On Dec 5, 10:00 pm, Edward Kozlowski <ekozlows...@gm ail.comwrote:
>
>
>

On Dec 5, 10:19 pm, Edward Kozlowski <ekozlows...@gm ail.comwrote:

>

On Dec 5, 6:22 pm, "Gabriel Genellina" <gagsl-...@yahoo.com.a rwrote:

>

En Wed, 05 Dec 2007 18:20:35 -0300, Bret <bret.wort...@g mail.comescribi ó:

>

I just tried changing this so that I now have a threading.Event ()
called self.done, which is set within the body of the shutdown()
method. The serverWrapper loop now looks like this:

>

def serverWrapper() :
while True:
server.handle_r equest()
if self.done.isSet ():
break

>

This works, but only if I follow the shutdown() rpc call a few seconds
later with ... something else to cause handle_request( ) to complete
again. Obviously, not quite the right approach....

>

You could try setting a reasonable timeout on the listening socket; I
would override the server_bind method, calling self.socket.set timeout(xxx)
before calling the inherited method. I've never actually done it with a
SimpleXMLRPCSer ver, but *should* work. Don't use a very small timeout,
because it affects *all* subsequent operations.

>

--
Gabriel Genellina

>

Try this:

>

def __init__(self, host, port):
self.done = False
server = SimpleXMLRPCSer ver((host, port))
:
: Bunch of server.register _function calls
:
def serverWrapper() :
try:
while not self.done:
server.handle_r equest()
except:
pass

>

Your shutdown method becomes:

>

def shutdown(self):
self.done = True

>

HTH

>

-Edward Kozlowski

>

Sorry about the first post, I shot from the hip and had to make a few
more modifications to make it 'working' code. The example below works
fine for me.

>

import SimpleXMLRPCSer ver

>

class myServer:
def __init__(self, host, port):
self.done = False
self.server = SimpleXMLRPCSer ver.SimpleXMLRP CServer((host,
port))

>

def shutdown(self):
self.done = True
return 0

>

def getName(self):
return "Hey, I'm Ed"

>

def serverWrapper(s elf):
self.server.reg ister_function( self.getName)
self.server.reg ister_function( self.shutdown)
try:
while not self.done:
self.server.han dle_request()
except:
pass

>

if __name__ == "__main__":
myServer('local host', 6058).serverWra pper()

>

---->>s.getName()
"Hey, I'm Ed"

>>s.shutdown( )

>

0

>
Thanks to all! I'm now keeping a file of my own snippets in hardcopy
so I won't lose them next time I change jobs. :-)
>
Bret

Oops, this actually misses part of the problem -- I need to construct
this server programmaticall y, so imbedding the call to start the
server in the "if __name__" construct doesn't work. If I start it
within the __init__, then the object that's creating it gets stuck
waiting for it to finish, which it never will. I need this to be
autonomous, which is why I was trying to do the start of the server in
a separate thread, but that doesn't seem to work either (that's what's
causing my process to need the second call; the thread completes the
loop and enters the next handle_request( ) call before the event or
boolean gets set).

Basically, I need a way for one server to start other autonomous
servers without waiting on them, and still retain the ability to shut
them down when their work is done.

Back to the keyboard. ;-)


Bret

[Bret]

Re: SimpleXMLRPCSer ver interruptable?

On Dec 6, 7:04 am, Bret <bret.wort...@g mail.comwrote:

On Dec 5, 10:00 pm, Edward Kozlowski <ekozlows...@gm ail.comwrote:
>
>
>

On Dec 5, 10:19 pm, Edward Kozlowski <ekozlows...@gm ail.comwrote:

>

On Dec 5, 6:22 pm, "Gabriel Genellina" <gagsl-...@yahoo.com.a rwrote:

>

En Wed, 05 Dec 2007 18:20:35 -0300, Bret <bret.wort...@g mail.comescribi ó:

>

I just tried changing this so that I now have a threading.Event ()
called self.done, which is set within the body of the shutdown()
method. The serverWrapper loop now looks like this:

>

def serverWrapper() :
while True:
server.handle_r equest()
if self.done.isSet ():
break

>

This works, but only if I follow the shutdown() rpc call a few seconds
later with ... something else to cause handle_request( ) to complete
again. Obviously, not quite the right approach....

>

You could try setting a reasonable timeout on the listening socket; I
would override the server_bind method, calling self.socket.set timeout(xxx)
before calling the inherited method. I've never actually done it with a
SimpleXMLRPCSer ver, but *should* work. Don't use a very small timeout,
because it affects *all* subsequent operations.

>

--
Gabriel Genellina

>

Try this:

>

def __init__(self, host, port):
self.done = False
server = SimpleXMLRPCSer ver((host, port))
:
: Bunch of server.register _function calls
:
def serverWrapper() :
try:
while not self.done:
server.handle_r equest()
except:
pass

>

Your shutdown method becomes:

>

def shutdown(self):
self.done = True

>

HTH

>

-Edward Kozlowski

>

Sorry about the first post, I shot from the hip and had to make a few
more modifications to make it 'working' code. The example below works
fine for me.

>

import SimpleXMLRPCSer ver

>

class myServer:
def __init__(self, host, port):
self.done = False
self.server = SimpleXMLRPCSer ver.SimpleXMLRP CServer((host,
port))

>

def shutdown(self):
self.done = True
return 0

>

def getName(self):
return "Hey, I'm Ed"

>

def serverWrapper(s elf):
self.server.reg ister_function( self.getName)
self.server.reg ister_function( self.shutdown)
try:
while not self.done:
self.server.han dle_request()
except:
pass

>

if __name__ == "__main__":
myServer('local host', 6058).serverWra pper()

>

---->>s.getName()
"Hey, I'm Ed"

>>s.shutdown( )

>

0

>
Thanks to all! I'm now keeping a file of my own snippets in hardcopy
so I won't lose them next time I change jobs. :-)
>
Bret

For completeness, what I ended up doing is this:

server = SimpleXMLRPCSer ver((host, port))
server.socket.s ettimeout(0.1)

ServerWrapper became:

def ServerWrapper() :
while True:
try:
server.handle_r equest()
if self.done.isSet ():
break
except timeout:
pass

And that seems to do the trick! Giving the socket a timeout allows me
to check the Event more frequently and catch the change within a
reasonable time.

Thanks again, Ed and Gabriel.


Bret

[Gabriel Genellina]

Re: SimpleXMLRPCSer ver interruptable?

En Thu, 06 Dec 2007 13:11:09 -0300, Bret <bret.wortman@g mail.comescribi ó:

For completeness, what I ended up doing is this:
>
server = SimpleXMLRPCSer ver((host, port))
server.socket.s ettimeout(0.1)
>
ServerWrapper became:
>
def ServerWrapper() :
while True:
try:
server.handle_r equest()
if self.done.isSet ():
break
except timeout:
pass
>
And that seems to do the trick! Giving the socket a timeout allows me
to check the Event more frequently and catch the change within a
reasonable time.

Remember that the timeout applies to *all* socket operations; what if the
XML request requires more than 0.1s to read?
If handling large requests is more important than the delay at shutdown
time, consider raising that value.

--
Gabriel Genellina

[Bret]

Re: SimpleXMLRPCSer ver interruptable?

On Dec 6, 7:43 pm, "Gabriel Genellina" <gagsl-...@yahoo.com.a rwrote:

En Thu, 06 Dec 2007 13:11:09 -0300, Bret <bret.wort...@g mail.comescribi ó:
>
>
>

For completeness, what I ended up doing is this:

>

server = SimpleXMLRPCSer ver((host, port))
server.socket.s ettimeout(0.1)

>

ServerWrapper became:

>

def ServerWrapper() :
while True:
try:
server.handle_r equest()
if self.done.isSet ():
break
except timeout:
pass

>

And that seems to do the trick! Giving the socket a timeout allows me
to check the Event more frequently and catch the change within a
reasonable time.

>
Remember that the timeout applies to *all* socket operations; what if the
XML request requires more than 0.1s to read?
If handling large requests is more important than the delay at shutdown
time, consider raising that value.
>
--
Gabriel Genellina

Good point. Thanks!