Return a string result with out breaking loop

[Andrew]

Hi I was wondering if there is anyway with XML RPC to send a string of
text from the server to the client with out calling return thus breaking
my loop

for example

def somefunc():
for action, files in results:
full_filename = os.path.join(pa th_to_watch, files)
theact = ACTIONS.get(act ion, "Unknown")
out2 = str(full_filena me) + " " + str(theact)
return out2

the return statement will return a result breaking my loop. My goal is
to have it continue looping and updating the client

any ideas?

Cheers

Andrew

Thanks in advance

Pyhon 2.5.2

Windows XP

[Christian Heimes]

Re: Return a string result with out breaking loop

Andrew wrote:

Hi I was wondering if there is anyway with XML RPC to send a string of
text from the server to the client with out calling return thus breaking
my loop
>
for example
>
def somefunc():
for action, files in results:
full_filename = os.path.join(pa th_to_watch, files)
theact = ACTIONS.get(act ion, "Unknown")
out2 = str(full_filena me) + " " + str(theact)
return out2
>
the return statement will return a result breaking my loop. My goal is
to have it continue looping and updating the client
>
any ideas?

Yes, use yield instead of return. It turns the function into a generator.

Christian

[Andrew]

Re: Return a string result with out breaking loop

Hi Ive been trying with yield all day and other different things :D

but I always get the same result using yield

Fault: <Fault 1: "<type 'exceptions.Typ eError'>:cannot marshal <type
'generator'

objects">

I'm not sure exactly what I am doing wrong as this is the first time Ive
used yield

Any suggestions on how to fix this error

Cheers

Andrew


Christian Heimes wrote:

Andrew wrote:

>Hi I was wondering if there is anyway with XML RPC to send a string of
>text from the server to the client with out calling return thus
>breaking my loop
>>
>for example
>>
> def somefunc():
> for action, files in results:
> full_filename = os.path.join(pa th_to_watch, files)
> theact = ACTIONS.get(act ion, "Unknown")
> out2 = str(full_filena me) + " " + str(theact)
> return out2
>>
>the return statement will return a result breaking my loop. My goal is
>to have it continue looping and updating the client
>>
>any ideas?

>
Yes, use yield instead of return. It turns the function into a generator.
>
Christian
>

[cnb]

Re: Return a string result with out breaking loop

def somefunc():
for action, files in results:
full_filename = os.path.join(pa th_to_watch, files)
theact = ACTIONS.get(act ion, "Unknown")
yield str(full_filena me) + " " + str(theact)



?


Here is an example if that doesn't work, using yield, to show how to
use yield:
def yi(x):
while x 0:
yield str(x)
x -= 1

>>yi(4)

<generator object at 0x01FA3C88>

>>a=yi(4)
>>a.next()

'4'

>>a.next()

'3'

>>a.next()

'2'

>>a.next()

'1'

>>a.next()

Traceback (most recent call last):
File "<pyshell#151>" , line 1, in <module>
a.next()
StopIteration

>>>

[cnb]

Re: Return a string result with out breaking loop

On Aug 26, 2:50 am, cnb <circularf...@y ahoo.sewrote:

def somefunc():
       for action, files in results:
               full_filename = os.path.join(pa th_to_watch, files)
               theact = ACTIONS.get(act ion, "Unknown")
               yield  str(full_filena me) +  " " + str(theact)
>
?
>
Here is an example if that doesn't work, using yield, to show how to
use yield:
def yi(x):
        while x 0:
                yield str(x)
                x -= 1
>

>yi(4)

>
<generator object at 0x01FA3C88>
>

>a=yi(4)
>a.next()

'4'

>a.next()

'3'

>a.next()

'2'

>a.next()

'1'

>a.next()

>
Traceback (most recent call last):
  File "<pyshell#151>" , line 1, in <module>
    a.next()
StopIteration
>
>
>
>

you can also do:
def yi(x):
while x 0:
yield str(x)
x -= 1

>>a = yi(10)
>>for x in a:

print x


10
9
8
7
6
5
4
3
2
1

>>>

[Andrew]

Re: Return a string result with out breaking loop

Yes I found many examples similiar to that but Yield still produces that
error

Sorry if I sound Novice but I have no formal education in programming so
understanding something takes me a bit longer than most of you guys :-D

Ive included a bit more of the function

How ever unimportant it may be


def watchos(self, path_to_watch=" C:\\"):
FILE_LIST_DIREC TORY = 0x0001
try: path_to_watch or "."
except: path_to_watch = "."
path_to_watch = os.path.abspath (path_to_watch)

out1 = "Watching %s at %s" % (path_to_watch, time.asctime()) + "\n\n"
while 1:

#INSERT MORE CODE HERE

results = change_handle
for action, files in results:
full_filename = os.path.join(pa th_to_watch, files)
theact = ACTIONS.get(act ion, "Unknown")
yield str(full_filena me) + " " + str(theact)

But I am having a hard time wrapping my head around yield... perhaps if
it produced more than the same error no matter what I did. I could try
and get a bit further

Anyway once again I appreciate the help cheers

:-)

[cnb]

Re: Return a string result with out breaking loop

ok post exactly what you do when this hapens:
ault: <Fault 1: "<type 'exceptions.Typ eError'>:cannot marshal <type
'generator'

objects">

it complains you are trying to marshal a generator object rather than
the file you are yielding.



also, something I am not sure about:

>>def f(x):

try: open("C:/ruby/progs/blandat/infixtoprefix.r b") or open(str(x))
except:print "hello"

>>f(12)
>>def f(x):

try: (open(str(x)) or open("C:/ruby/progs/blandat/infixtoprefix.r b"))
except:print "hello"

>>f(12)

hello

>>>

the or doesnt seem to work as expected. but thats not the problem youa
re experienceing

[Andrew]

Re: Return a string result with out breaking loop

I run the server then execute the client. From the client I execute the
function key.watchos()

My goal is an administration tool

and this is just a function in my goal :-)



Microsoft Windows XP [Version 5.1.2600]
(C) Copyright 1985-2001 Microsoft Corp.

C:\Documents and Settings\Maboro shi>python C:\software\mab ssystem\client. py
Use the keyword, "key" to interact with the server

>>key.watchos ()

Traceback (most recent call last):
File "<console>" , line 1, in <module>
File "C:\Python25\li b\xmlrpclib.py" , line 1147, in __call__
return self.__send(sel f.__name, args)
File "C:\Python25\li b\xmlrpclib.py" , line 1437, in __request
verbose=self.__ verbose
File "C:\Python25\li b\xmlrpclib.py" , line 1201, in request
return self._parse_res ponse(h.getfile (), sock)
File "C:\Python25\li b\xmlrpclib.py" , line 1340, in _parse_response
return u.close()
File "C:\Python25\li b\xmlrpclib.py" , line 787, in close
raise Fault(**self._s tack[0])
Fault: <Fault 1: "<type 'exceptions.Typ eError'>:cannot marshal <type
'generator'

objects">

>>>

the function watchos is basically based off of Tim Goldens Directory
watching app

the function is as follows in entirety

def watchos(self, path_to_watch=" C:\\"):
#get path or maintain current path of app
FILE_LIST_DIREC TORY = 0x0001
try: path_to_watch or "."
except: path_to_watch = "."
path_to_watch = os.path.abspath (path_to_watch)

out1 = "Watching %s at %s" % (path_to_watch, time.asctime()) +
"\n\n"
# FindFirstChange Notification sets up a handle for watching
# file changes.
while 1:

hDir = win32file.Creat eFile (
path_to_watch,
FILE_LIST_DIREC TORY,
win32con.FILE_S HARE_READ | win32con.FILE_S HARE_WRITE,
None,
win32con.OPEN_E XISTING,
win32con.FILE_F LAG_BACKUP_SEMA NTICS,
None
)

change_handle = win32file.ReadD irectoryChanges W (
hDir,
1024,
True,#Heap Size include_subdire ctories,
win32con.FILE_N OTIFY_CHANGE_FI LE_NAME |
win32con.FILE_N OTIFY_CHANGE_DI R_NAME |
win32con.FILE_N OTIFY_CHANGE_AT TRIBUTES |
win32con.FILE_N OTIFY_CHANGE_SI ZE |
win32con.FILE_N OTIFY_CHANGE_LA ST_WRITE |
win32con.FILE_N OTIFY_CHANGE_SE CURITY,
None,
None
)

# Loop forever, listing any file changes. The WaitFor... will
# time out every half a second allowing for keyboard
interrupts
# to terminate the loop.
ACTIONS = {
1 : "Created",
2 : "Deleted",
3 : "Updated",
4 : "Renamed from something",
5 : "Renamed to something"
}

results = change_handle
for action, files in results:
full_filename = os.path.join(pa th_to_watch, files)
theact = ACTIONS.get(act ion, "Unknown")
yield str(full_filena me) + " " + str(theact)


and the rpc client is as follows

import xmlrpclib, code

# Specify IP of Server here defualt port is 9000
url = "http://127.0.0.1:8888"
sock = xmlrpclib.Serve rProxy(url, allow_none=True , verbose=0)
# use the interactive console to interact example "key.keyit( )" will
start the logger
interp = code.Interactiv eConsole({'key' : sock})
interp.interact ("Use the keyword, \"key\" to interact with the server")

Sorry if I posted to much code :-)

Thank you in advance

[alex23]

Re: Return a string result with out breaking loop

On Aug 26, 12:14 pm, Andrew <nob...@yahoo.c omwrote:

I run the server then execute the client. From the client I execute the
function key.watchos()
Sorry if I posted to much code :-)

The problem is the Python implementation of XML-RPC _can't_ send
generators (which is what the 'unable to marshal' error is telling
you). From the docs:

"Types that are conformable (e.g. that can be marshalled through XML),
include the following (and except where noted, they are unmarshalled
as the same Python type): [boolean, integers, floating-point numbers,
strings, arrays, structures (dicts), dates, binary dates]"

I'm not sure how to easily fix this to achieve what you want, though.

[castironpi]

Re: Return a string result with out breaking loop

On Aug 25, 6:37 pm, Andrew <nob...@yahoo.c omwrote:

Hi I was wondering if there is anyway with XML RPC to send a string of
text from the server to the client with out calling return thus breaking
  my loop
>
for example
>
  def somefunc():
       for action, files in results:
               full_filename = os.path.join(pa th_to_watch, files)
               theact = ACTIONS.get(act ion, "Unknown")
               out2 =  str(full_filena me) +  " " + str(theact)
               return out2
>
the return statement will return a result breaking my loop. My goal is
to have it continue looping and updating the client
>
any ideas?
>
Cheers
>
Andrew
>
Thanks in advance
>
Pyhon 2.5.2
>
Windows XP

Andrew,

I have generators working on both sides of a SimpleXMLRPCSer ver
instance. You ask for a server-side generator, and I won't post the
whole program, as it's long, so here's an important part:

server = SimpleXMLRPCSer ver(("localhost ", 8000))
server.register _introspection_ functions()

def gen( ):
while 1:
yield 1
yield 2
yield 3

servg= gen( )
server.register _function( servg.next, 'gen' )

Called 's.gen( )' four times, output:

localhost - - [25/Aug/2008 23:08:28] "POST /RPC2 HTTP/1.0" 200 -
1
localhost - - [25/Aug/2008 23:08:29] "POST /RPC2 HTTP/1.0" 200 -
2
localhost - - [25/Aug/2008 23:08:30] "POST /RPC2 HTTP/1.0" 200 -
3
localhost - - [25/Aug/2008 23:08:31] "POST /RPC2 HTTP/1.0" 200 -
1

As expected. I guess that your problem was on this line:

server.register _function( servg.next, 'gen' )

where instead you just wrote

server.register _function( servg, 'gen' ) #wrong

or perhaps even

server.register _function( gen, 'gen' ) #wrong

I'll offer an explanation of the difference too, for the asking.

[Andrew]

Re: Return a string result with out breaking loop

Hi I have done this without error

:D

Yield returns the result I am looking for... however it does not
continue looping. It does the same thing as return would

any suggestions

my code is as follows

serveraddr = ('', 8888)
srvr = ThreadingServer (serveraddr, SimpleXMLRPCReq uestHandler,
allow_none=True )

srvr.register_i nstance(theApp( ))

srvr.register_i ntrospection_fu nctions()

def watchos(path_to _watch="C:\\"):
#get path or maintain current path of app
FILE_LIST_DIREC TORY = 0x0001
try: path_to_watch or "."
except: path_to_watch = "."
path_to_watch = os.path.abspath (path_to_watch)

out1 = "Watching %s at %s" % (path_to_watch, time.asctime()) + "\n\n"
# FindFirstChange Notification sets up a handle for watching
# file changes.
while 1:

hDir = win32file.Creat eFile (
path_to_watch,
FILE_LIST_DIREC TORY,
win32con.FILE_S HARE_READ | win32con.FILE_S HARE_WRITE,
None,
win32con.OPEN_E XISTING,
win32con.FILE_F LAG_BACKUP_SEMA NTICS,
None
)

change_handle = win32file.ReadD irectoryChanges W (
hDir,
1024,
True,#Heap Size include_subdire ctories,
win32con.FILE_N OTIFY_CHANGE_FI LE_NAME |
win32con.FILE_N OTIFY_CHANGE_DI R_NAME |
win32con.FILE_N OTIFY_CHANGE_AT TRIBUTES |
win32con.FILE_N OTIFY_CHANGE_SI ZE |
win32con.FILE_N OTIFY_CHANGE_LA ST_WRITE |
win32con.FILE_N OTIFY_CHANGE_SE CURITY,
None,
None
)

# Loop forever, listing any file changes. The WaitFor... will
# time out every half a second allowing for keyboard interrupts
# to terminate the loop.
ACTIONS = {
1 : "Created",
2 : "Deleted",
3 : "Updated",
4 : "Renamed from something",
5 : "Renamed to something"
}

results = change_handle
for action, files in results:
full_filename = os.path.join(pa th_to_watch, files)
theact = ACTIONS.get(act ion, "Unknown")
out2 = str(full_filena me) + " " + str(theact)
yield str(out2)

servg = watchos()
srvr.register_f unction(servg.n ext, 'watchos')

srvr.register_m ulticall_functi ons()
srvr.serve_fore ver()

[Fredrik Lundh]

Re: Return a string result with out breaking loop

Andrew wrote:

Yield returns the result I am looking for... however it does not
continue looping. It does the same thing as return would

the XML-RPC protocol doesn't really support your use case; for each
call, the client issues a complete request package, and the server
produces a complete response in return.

</F>

[Andrew]

Re: Return a string result with out breaking loop

mmk guess I will have to look for alternate solutions for this project.
Thank you all for your help

cheers Andrew!

Fredrik Lundh wrote:

Andrew wrote:
>

>Yield returns the result I am looking for... however it does not
>continue looping. It does the same thing as return would

>
the XML-RPC protocol doesn't really support your use case; for each
call, the client issues a complete request package, and the server
produces a complete response in return.
>
</F>
>

[castironpi]

Re: Return a string result with out breaking loop

On Aug 26, 11:46 am, Andrew <nob...@yahoo.c omwrote:
...

         results = change_handle
         for action, files in results:
             full_filename = os.path.join(pa th_to_watch, files)
             theact = ACTIONS.get(act ion, "Unknown")
             out2 = str(full_filena me) +  " " + str(theact)
         yield str(out2)

I think you have the yield in the wrong place. Should you tab it over
one?