logging exceptions

[Alexandru Mosoi]

why doesn't logging throw any exception when it should? how do I
configure logging to throw exceptions?

>>try:

.... logging.fatal(' asdf %d', '123')
.... except:
.... print 'this line is never printed'
....
Traceback (most recent call last):
File "/Library/Frameworks/Python.framewor k/Versions/2.5/lib/
python2.5/logging/__init__.py", line 744, in emit
msg = self.format(rec ord)
File "/Library/Frameworks/Python.framewor k/Versions/2.5/lib/
python2.5/logging/__init__.py", line 630, in format
return fmt.format(reco rd)
File "/Library/Frameworks/Python.framewor k/Versions/2.5/lib/
python2.5/logging/__init__.py", line 418, in format
record.message = record.getMessa ge()
File "/Library/Frameworks/Python.framewor k/Versions/2.5/lib/
python2.5/logging/__init__.py", line 288, in getMessage
msg = msg % self.args
TypeError: int argument required

[Rob Wolfe]

Re: logging exceptions



Alexandru Mosoi napisa³(a):

why doesn't logging throw any exception when it should? how do I
configure logging to throw exceptions?
>

>try:

... logging.fatal(' asdf %d', '123')
... except:
... print 'this line is never printed'
...

[...]

You need to subclass your handler and redefine `handleError` method.
See: http://docs.python.org/lib/node409.html

HTH,
Rob

[Vinay Sajip]

Re: logging exceptions

On Aug 26, 10:36 am, Alexandru Mosoi <brtz...@gmail. comwrote:

why doesn'tloggingt hrow any exception when it should? how do I
configureloggin gto throw exceptions?
>

>try:

>
... logging.fatal(' asdf %d', '123')
... except:
... print 'this line is never printed'
...
Traceback (most recent call last):
File "/Library/Frameworks/Python.framewor k/Versions/2.5/lib/
python2.5/logging/__init__.py", line 744, in emit
msg = self.format(rec ord)
File "/Library/Frameworks/Python.framewor k/Versions/2.5/lib/
python2.5/logging/__init__.py", line 630, in format
return fmt.format(reco rd)
File "/Library/Frameworks/Python.framewor k/Versions/2.5/lib/
python2.5/logging/__init__.py", line 418, in format
record.message = record.getMessa ge()
File "/Library/Frameworks/Python.framewor k/Versions/2.5/lib/
python2.5/logging/__init__.py", line 288, in getMessage
msg = msg % self.args
TypeError: int argument required

Was your traceback from the snippet you posted? If it was, then the
exception (a TypeError) *is* being raised from logging. So I don't
understand your question "why doesn't logging throw any exception when
it should?", because logging is raising an exception here.

To cause logging to *not* raise exceptions, set
logging.raiseEx ceptions to 0 (default is 1). The raiseExceptions
variable would normally be set to 0 in a production environment, where
you don't want logging-related exceptions to bring an application
down.

Regards,

Vinay Sajip

[Rob Wolfe]

Re: logging exceptions



Vinay Sajip napisa³(a):

On Aug 26, 10:36 am, Alexandru Mosoi <brtz...@gmail. comwrote:

why doesn'tloggingt hrow any exception when it should? how do I
configureloggin gto throw exceptions?

>>try:

... logging.fatal(' asdf %d', '123')
... except:
... print 'this line is never printed'
...
Traceback (most recent call last):
File "/Library/Frameworks/Python.framewor k/Versions/2.5/lib/
python2.5/logging/__init__.py", line 744, in emit
msg = self.format(rec ord)
File "/Library/Frameworks/Python.framewor k/Versions/2.5/lib/
python2.5/logging/__init__.py", line 630, in format
return fmt.format(reco rd)
File "/Library/Frameworks/Python.framewor k/Versions/2.5/lib/
python2.5/logging/__init__.py", line 418, in format
record.message = record.getMessa ge()
File "/Library/Frameworks/Python.framewor k/Versions/2.5/lib/
python2.5/logging/__init__.py", line 288, in getMessage
msg = msg % self.args
TypeError: int argument required

>
Was your traceback from the snippet you posted? If it was, then the
exception (a TypeError) *is* being raised from logging. So I don't
understand your question "why doesn't logging throw any exception when
it should?", because logging is raising an exception here.

No, it isn't.
This traceback is *printed* in `Handler.handle Error` method:

<code from logging>
__version__ = "0.5.0.2"

[...]

def handleError(sel f, record):
"""
Handle errors which occur during an emit() call.

This method should be called from handlers when an exception
is
encountered during an emit() call. If raiseExceptions is
false,
exceptions get silently ignored. This is what is mostly wanted
for a logging system - most users will not care about errors
in
the logging system, they are more interested in application
errors.
You could, however, replace this with a custom handler if you
wish.
The record which was being processed is passed in to this
method.
"""
if raiseExceptions :
ei = sys.exc_info()
traceback.print _exception(ei[0], ei[1], ei[2], None,
sys.stderr)
del ei

</code from logging>

>
To cause logging to *not* raise exceptions, set
logging.raiseEx ceptions to 0 (default is 1). The raiseExceptions
variable would normally be set to 0 in a production environment, where
you don't want logging-related exceptions to bring an application
down.

Well, I think that it will not help. The exception will be printed
not raised. The only solution is to redefine `handleError` method
or maybe I've missed something?

Br,
Rob

[Vinay Sajip]

Re: logging exceptions

On Aug 27, 10:30 am, Rob Wolfe <r...@smsnet.pl wrote:

Vinay Sajip napisa³(a):
>
>
>

On Aug 26, 10:36 am, Alexandru Mosoi <brtz...@gmail. comwrote:

why doesn'tloggingt hrow any exception when it should? how do I
configureloggin gto throw exceptions?

>

>try:

>

... logging.fatal(' asdf %d', '123')
... except:
... print 'this line is never printed'
...
Traceback (most recent call last):
File "/Library/Frameworks/Python.framewor k/Versions/2.5/lib/
python2.5/logging/__init__.py", line 744, in emit
msg = self.format(rec ord)
File "/Library/Frameworks/Python.framewor k/Versions/2.5/lib/
python2.5/logging/__init__.py", line 630, in format
return fmt.format(reco rd)
File "/Library/Frameworks/Python.framewor k/Versions/2.5/lib/
python2.5/logging/__init__.py", line 418, in format
record.message = record.getMessa ge()
File "/Library/Frameworks/Python.framewor k/Versions/2.5/lib/
python2.5/logging/__init__.py", line 288, in getMessage
msg = msg % self.args
TypeError: int argument required

>

Was your traceback from the snippet you posted? If it was, then the
exception (a TypeError) *is* being raised fromlogging. So I don't
understand your question "why doesn'tloggingt hrow any exception when
it should?", becauseloggingi s raising an exception here.

>
No, it isn't.
This traceback is *printed* in `Handler.handle Error` method:
>

You're right - silly me. I wasn't paying attention :-(

variable would normally be set to 0 in a production environment, where
you don't wantlogging-related exceptions to bring an application
down.

>
Well, I think that it will not help. The exception will be printed
not raised. The only solution is to redefine `handleError` method
or maybe I've missed something?
>

No, you're right. To do custom handling of exceptions, handleError
needs to be overridden.

Regards,

Vinay