Multiline log records in syslog

Question

So I've configured my Python application to log to syslog with Python's SysLogHandler, and everything works fine. Except for multi-line handling. Not that I need to emit multiline log records so badly (I do a little), but I need to be able to read Python's exceptions. I'm using Ubuntu with rsyslog 4.2.0. This is what I'm getting:

Mar 28 20:11:59 telemachos root: ERROR 'EXCEPTION'#012Traceback (most recent call last):#012  File "./test.py", line 22, in <module>#012    foo()#012  File "./test.py", line 13, in foo#012    bar()#012  File "./test.py", line 16, in bar#012    bla()#012  File "./test.py", line 19, in bla#012    raise Exception("EXCEPTION!")#012Exception: EXCEPTION!

Test code in case you need it:

import logging
from logging.handlers import SysLogHandler

logger = logging.getLogger()
logger.setLevel(logging.INFO)
syslog = SysLogHandler(address='/dev/log', facility='local0')
formatter = logging.Formatter('%(name)s: %(levelname)s %(message)r')
syslog.setFormatter(formatter)
logger.addHandler(syslog)

def foo():
    bar()

def bar():
    bla()

def bla():
    raise Exception("EXCEPTION!")

try:
    foo()
except:
    logger.exception("EXCEPTION")

Answer 1

OK, figured it out finally...

rsyslog by default escapes all weird characters (ASCII < 32), and this include newlines (as well as tabs and others).

$EscapeControlCharactersOnReceive:

This directive instructs rsyslogd to replace control characters during reception of the message. The intent is to provide a way to stop non-printable messages from entering the syslog system as whole. If this option is turned on, all control-characters are converted to a 3-digit octal number and be prefixed with the $ControlCharacterEscapePrefix character (being ‘\’ by default). For example, if the BEL character (ctrl-g) is included in the message, it would be converted to “\007”.

You can simply add this to your rsyslog config to turn it off:

$EscapeControlCharactersOnReceive off

or, with the "new" advanced syntax:

global(parser.escapeControlCharactersOnReceive="off")