How to log to journald (systemd) via Python?
Question:
I would like logging.info() to go to journald (systemd).
Up to now I only found python modules which read journald (not what I want) or modules which work like this: journal.send('Hello world')
Answers:
python-systemd has a JournalHandler you can use with the logging framework.
From the documentation:
import logging
from systemd.journal import JournalHandler
log = logging.getLogger('demo')
log.addHandler(JournalHandler())
log.setLevel(logging.INFO)
log.info("sent to journal")
An alternative to the official package, the systemd package works with python 3.6. Its source is also on github.
The implementation is a mirror of the official lib, with some minor changes:
import logging
from systemd import journal
log = logging.getLogger('demo')
log.addHandler(journal.JournaldLogHandler())
log.setLevel(logging.INFO)
log.info("sent to journal")
or for an even shorter method:
from systemd import journal
journal.write("Hello Lennart")
This is a solution without third party modules.
It works fine for me and the messages show up in journald.
import logging
import sys
logger = logging.getLogger(__name__)
logger.setLevel(logging.INFO)
# this is just to make the output look nice
formatter = logging.Formatter(fmt="%(asctime)s %(name)s.%(levelname)s: %(message)s", datefmt="%Y.%m.%d %H:%M:%S")
# this logs to stdout and I think it is flushed immediately
handler = logging.StreamHandler(stream=sys.stdout)
handler.setFormatter(formatter)
logger.addHandler(handler)
logger.info('test')
This is an alternative solution without third party modules
import subprocess
data = "sent to journal"
echoCmd = ["echo", data]
sysdCat = ["systemd-cat", "-p", "info"]
echoResult = subprocess.Popen(echoCmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
sysdCatResult = subprocess.Popen(sysdCat, stdin=echoResult.stdout)
sysdCatResult.communicate()
```
I would like logging.info() to go to journald (systemd).
Up to now I only found python modules which read journald (not what I want) or modules which work like this: journal.send('Hello world')
python-systemd has a JournalHandler you can use with the logging framework.
From the documentation:
import logging
from systemd.journal import JournalHandler
log = logging.getLogger('demo')
log.addHandler(JournalHandler())
log.setLevel(logging.INFO)
log.info("sent to journal")
An alternative to the official package, the systemd package works with python 3.6. Its source is also on github.
The implementation is a mirror of the official lib, with some minor changes:
import logging
from systemd import journal
log = logging.getLogger('demo')
log.addHandler(journal.JournaldLogHandler())
log.setLevel(logging.INFO)
log.info("sent to journal")
or for an even shorter method:
from systemd import journal
journal.write("Hello Lennart")
This is a solution without third party modules.
It works fine for me and the messages show up in journald.
import logging
import sys
logger = logging.getLogger(__name__)
logger.setLevel(logging.INFO)
# this is just to make the output look nice
formatter = logging.Formatter(fmt="%(asctime)s %(name)s.%(levelname)s: %(message)s", datefmt="%Y.%m.%d %H:%M:%S")
# this logs to stdout and I think it is flushed immediately
handler = logging.StreamHandler(stream=sys.stdout)
handler.setFormatter(formatter)
logger.addHandler(handler)
logger.info('test')
This is an alternative solution without third party modules
import subprocess
data = "sent to journal"
echoCmd = ["echo", data]
sysdCat = ["systemd-cat", "-p", "info"]
echoResult = subprocess.Popen(echoCmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
sysdCatResult = subprocess.Popen(sysdCat, stdin=echoResult.stdout)
sysdCatResult.communicate()
```