journald-native
A systemd-journal native logging lib wrapper. See sd-journal help for more info
Installation
Run
gem install journald-native
or add
gem 'journald-native', '~> 1.0.11'
to your Gemfile.
Please note that you need a systemd development package installed in your system like systemd-devel
in Fedora, libsystemd-dev
in Debian, also may be a separate package for journal in older systems like libsystemd-journal-dev
.
NB: The gem can be installed on non-linux system but it will do nothing there. (Functions will return success without any actual effect)
Usage
require 'journald/native'
Constants
Constants are used to denote a log level
Available constants:
Journald::LOG_EMERG # system is unusable
Journald::LOG_ALERT # action must be taken immediately
Journald::LOG_CRIT # critical conditions
Journald::LOG_ERR # error conditions
Journald::LOG_WARNING # warning conditions
Journald::LOG_NOTICE # normal but significant condition
Journald::LOG_INFO # informational
Journald::LOG_DEBUG # debug-level messages
systemd-journal uses syslog constants to denote level therefore they are equal to those of the Syslog module,
e.g. Journald::LOG_WARNING == Syslog::LOG_WARNING
.
See syslog man page for more info
Methods
Methods of Journald::Native class wrap systemd-journal calls. See sd-journal help for more info
Journald::Native.sd_journal_send "MESSAGE=message", "PRIORITY=#{Journald::LOG_WARNING}"
Journald::Native.sd_journal_print Journald::LOG_WARNING, "message"
Journald::Native.sd_journal_perror "message"
It is not recommended to use sd_journal_print
and sd_journal_perror
as you may get exception
if your string contains '\0'
byte due to C zero-terminated string format.
On the contrary sd_journal_send
uses binary buffers and does not have this shortcoming.
Short aliases
Versions prior to 1.0.11 used short function names that are available now as aliases. They will probably throw a deprecation warning in 1.1 and be removed in 2.0 should these versions ever happen.
Journald::Native.sd_journal_send
can be called as Journald::Native.send
Journald::Native.sd_journal_print
can be called as Journald::Native.print
Journald::Native.sd_journal_perror
can be called as Journald::Native.perror
Please note that send
method is overridden.
This is a bad practice and a reason why longer names were introduced later
Authors
This library was written by Anton Smirnov and currently maintained by https://www.theforeman.org developers.
License
Copyright (c) 2014 Anton Smirnov
This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
You can find a copy of the GNU Lesser General Public License in COPYING.md or at https://www.gnu.org/licenses/lgpl-2.1.txt.