Newbie: how to wait for callbacks...

[Jan Bakuwel]

Hoi all,

I'm trying to write a little code that waits for a callback routine to
be called, ideally with a timeout...

I guess the code below is not right (using a boolean flag), but since
I'm new to Python, I don't know yet where the semaphores live and/or
whether I'm on the right track...

Any help is much appreciated...

Jan


def processEmail(emailMessage):

sendSent = False

def sendComplete(result):
print "Message sent successfully"
processEmail.sendSent = True
#end sendComplete

def sendFailed(error):
print >> sys.stderr, "Error", error.getErrorMessage()
processEmail.sendSent = True
#end sendFailed

if emailMessage.is_multipart():
print "...multipart"
for pl in emailMessage.walk():
pass
else:
print "...not multipart"
# simulate some processing that will take place here
time.sleep(1)

multiMessage = MIMEMultipart()
multiMessage['From'] = emailMessage['From']
multiMessage['To'] = emailMessage['To']
multiMessage['Subject'] = emailMessage['Subject']
messageData = multiMessage.as_string(unixfrom=False)
sending = smtp.sendmail('smtp', '(e-mail address removed)', '(e-mail address removed)', messageData)
sending.addCallback(sendComplete).addErrback(sendFailed)

while not processEmail.sendSent:
print "z"
time.sleep(0.1)
#end while

print "...done"
#raise smtp.SMTPDeliveryError(code=550, resp="Unable to deliver
email, please try again later", isFatal=True, retry=False)
print ""
#endif

#end ProcessEmail

 

[jeff.clough]

Hoi all,

I'm trying to write a little code that waits for a callback routine to
be called, ideally with a timeout...

I guess the code below is not right (using a boolean flag), but since
I'm new to Python, I don't know yet where the semaphores live and/or
whether I'm on the right track...

Any help is much appreciated...

Jan

def processEmail(emailMessage):

sendSent = False

def sendComplete(result):
print "Message sent successfully"
processEmail.sendSent = True
#end sendComplete

def sendFailed(error):
print >> sys.stderr, "Error", error.getErrorMessage()
processEmail.sendSent = True
#end sendFailed

if emailMessage.is_multipart():
print "...multipart"
for pl in emailMessage.walk():
pass
else:
print "...not multipart"
# simulate some processing that will take place here
time.sleep(1)

multiMessage = MIMEMultipart()
multiMessage['From'] = emailMessage['From']
multiMessage['To'] = emailMessage['To']
multiMessage['Subject'] = emailMessage['Subject']
messageData = multiMessage.as_string(unixfrom=False)
sending = smtp.sendmail('smtp', '(e-mail address removed)', '(e-mail address removed)', messageData)
sending.addCallback(sendComplete).addErrback(sendFailed)

while not processEmail.sendSent:
print "z"
time.sleep(0.1)
#end while

print "...done"
#raise smtp.SMTPDeliveryError(code=550, resp="Unable to deliver
email, please try again later", isFatal=True, retry=False)
print ""
#endif

#end ProcessEmail

For semaphores, check out the mutex module
(http://docs.python.org/lib/module-mutex.html). For timeouts, look at
the alarm signal in the signal module
(http://docs.python.org/lib/module-signal.html).

--Jeff