summaryrefslogtreecommitdiff
path: root/src/python-systemd/journal.py
diff options
context:
space:
mode:
authorMarti Raudsepp <marti@juffo.org>2012-10-09 18:12:02 +0300
committerZbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl>2012-11-13 11:13:52 +0100
commit73c0495f6830ca99c0c6eb15e83c3c7d44096d19 (patch)
treee14a8e9a09918c67e820a20166a119eb25cde458 /src/python-systemd/journal.py
parent568c7e02372ff7b8eb41172ad7c3a426723512f8 (diff)
python: add journal backend for the logging framework
Supports Python versions 2.6 through 3.3 (tested on 2.7 and 3.2). See JournalHandler docstring for usage details. [zj: - use send() instead of using sendv() directly - do exception handling like in the logging module - bumped min version to python2.6, since the module does not work with python2.5 anyway ]
Diffstat (limited to 'src/python-systemd/journal.py')
-rw-r--r--src/python-systemd/journal.py85
1 files changed, 85 insertions, 0 deletions
diff --git a/src/python-systemd/journal.py b/src/python-systemd/journal.py
index 760d2db014..516ca1ab56 100644
--- a/src/python-systemd/journal.py
+++ b/src/python-systemd/journal.py
@@ -19,6 +19,7 @@
import traceback as _traceback
import os as _os
+import logging as _logging
from syslog import (LOG_EMERG, LOG_ALERT, LOG_CRIT, LOG_ERR,
LOG_WARNING, LOG_NOTICE, LOG_INFO, LOG_DEBUG)
from ._journal import sendv, stream_fd
@@ -114,3 +115,87 @@ def stream(identifier, priority=LOG_DEBUG, level_prefix=False):
fd = stream_fd(identifier, priority, level_prefix)
return _os.fdopen(fd, 'w', 1)
+
+class JournalHandler(_logging.Handler):
+ """Journal handler class for the Python logging framework.
+
+ Please see the Python logging module documentation for an
+ overview: http://docs.python.org/library/logging.html
+
+ To create a custom logger whose messages go only to journal:
+
+ >>> log = logging.getLogger('custom_logger_name')
+ >>> log.propagate = False
+ >>> log.addHandler(journal.JournalHandler())
+ >>> log.warn("Some message: %s", detail)
+
+ Note that by default, message levels INFO and DEBUG are ignored
+ by the logging framework. To enable those log levels:
+
+ >>> log.setLevel(logging.DEBUG)
+
+ To attach journal MESSAGE_ID, an extra field is supported:
+
+ >>> log.warn("Message with ID",
+ >>> extra={'MESSAGE_ID': '22bb01335f724c959ac4799627d1cb61'})
+
+ To redirect all logging messages to journal regardless of where
+ they come from, attach it to the root logger:
+
+ >>> logging.root.addHandler(journal.JournalHandler())
+
+ For more complex configurations when using dictConfig or
+ fileConfig, specify 'systemd.journal.JournalHandler' as the
+ handler class. Only standard handler configuration options
+ are supported: level, formatter, filters.
+
+ The following journal fields will be sent:
+
+ MESSAGE, PRIORITY, THREAD_NAME, CODE_FILE, CODE_LINE,
+ CODE_FUNC, LOGGER (name as supplied to getLogger call),
+ MESSAGE_ID (optional, see above).
+ """
+
+ def emit(self, record):
+ """Write record as journal event.
+
+ MESSAGE is taken from the message provided by the
+ user, and PRIORITY, LOGGER, THREAD_NAME,
+ CODE_{FILE,LINE,FUNC} fields are appended
+ automatically. In addition, record.MESSAGE_ID will be
+ used if present.
+ """
+ try:
+ msg = self.format(record)
+ pri = self.mapPriority(record.levelno)
+ mid = getattr(record, 'MESSAGE_ID', None)
+ send(msg,
+ MESSAGE_ID=mid,
+ PRIORITY=format(pri),
+ LOGGER=record.name,
+ THREAD_NAME=record.threadName,
+ CODE_FILE=record.pathname,
+ CODE_LINE=record.lineno,
+ CODE_FUNC=record.funcName)
+ except Exception:
+ self.handleError(record)
+
+ @staticmethod
+ def mapPriority(levelno):
+ """Map logging levels to journald priorities.
+
+ Since Python log level numbers are "sparse", we have
+ to map numbers in between the standard levels too.
+ """
+ if levelno <= _logging.DEBUG:
+ return LOG_DEBUG
+ elif levelno <= _logging.INFO:
+ return LOG_INFO
+ elif levelno <= _logging.WARNING:
+ return LOG_WARNING
+ elif levelno <= _logging.ERROR:
+ return LOG_ERR
+ elif levelno <= _logging.CRITICAL:
+ return LOG_CRIT
+ else:
+ return LOG_ALERT