class Syslog::Logger
Syslog::Logger is a Logger work-alike that logs via syslog instead of to a file. You can use Syslog::Logger to aggregate logs between multiple machines.
By default, Syslog::Logger uses the program name 'ruby', but this can be changed via the first argument to ::new.
NOTE! You can only set the Syslog::Logger program name when you initialize Syslog::Logger for the first time. This is a limitation of the way Syslog::Logger uses syslog (and in some ways, a limitation of the way syslog(3) works). Attempts to change Syslog::Logger's program name after the first initialization will be ignored.
Example
The following will log to syslogd on your local machine:
require 'syslog/logger' log = Syslog::Logger.new 'my_program' log.info 'this line will be logged via syslog(3)'
Also the facility may be set to specify the facility level which will be used:
log.info 'this line will be logged using Syslog default facility level' log_local1 = Syslog::Logger.new 'my_program', Syslog::LOG_LOCAL1 log_local1.info 'this line will be logged using local1 facility level'
You may need to perform some syslog.conf setup first. For a BSD machine add the following lines to /etc/syslog.conf:
!my_program *.* /var/log/my_program.log
Then touch /var/log/my_program.log and signal syslogd with a HUP (killall -HUP syslogd, on FreeBSD).
If you wish to have logs automatically roll over and archive, see the newsyslog.conf(5) and newsyslog(8) man pages.
Constants
- LEVEL_MAP
-
Maps Logger warning types to syslog(3) warning types.
Messages from Ruby applications are not considered as critical as messages from other system daemons using syslog(3), so most messages are reduced by one level. For example, a fatal message for Ruby's Logger is considered an error for syslog(3).
- VERSION
-
The version of Syslog::Logger you are using.
Attributes
The facility argument is used to specify what type of program is logging the message.
Logging formatter, as a Proc
that will take four arguments and return the formatted message. The arguments are:
-
severity
-
The Severity of the log message.
-
time
-
A Time instance representing when the message was logged.
-
progname
-
The progname configured, or passed to the logger method.
-
msg
-
The Object the user passed to the log message; not necessarily a String.
The block should return an Object that can be written to the logging device via write
. The default formatter is used when no formatter is set.
Log level for Logger compatibility.
Public Class Methods
# File ext/syslog/lib/syslog/logger.rb, line 106 def self.make_methods meth level = ::Logger.const_get(meth.upcase) eval " def #{meth}(message = nil, &block) add(#{level}, message, &block) end def #{meth}? @level <= #{level} end ", nil, __FILE__, __LINE__ + 1 end
Builds a methods for level meth
.
# File ext/syslog/lib/syslog/logger.rb, line 190 def initialize program_name = 'ruby', facility = nil @level = ::Logger::DEBUG @formatter = Formatter.new @@syslog ||= Syslog.open(program_name) @facility = (facility || @@syslog.facility) end
Fills in variables for Logger compatibility. If this is the first instance of Syslog::Logger, program_name
may be set to change the logged program name. The facility
may be set to specify the facility level which will be used.
Due to the way syslog works, only one program name may be chosen.
# File ext/syslog/lib/syslog/logger.rb, line 92 def self.syslog @@syslog end
Returns the internal Syslog object that is initialized when the first instance is created.
# File ext/syslog/lib/syslog/logger.rb, line 99 def self.syslog= syslog @@syslog = syslog end
Specifies the internal Syslog object to be used.
Public Instance Methods
# File ext/syslog/lib/syslog/logger.rb, line 202 def add severity, message = nil, progname = nil, &block severity ||= ::Logger::UNKNOWN @level <= severity and @@syslog.log( (LEVEL_MAP[severity] | @facility), '%s', formatter.call(severity, Time.now, progname, (message || block.call)) ) true end
Almost duplicates #add. progname
is ignored.
# File ext/syslog/lib/syslog/logger.rb, line 155
Logs a message
at the debug (syslog debug) log level, or logs the message returned from the block.
# File ext/syslog/lib/syslog/logger.rb, line 137
Logs a message
at the error (syslog warning) log level, or logs the message returned from the block.
# File ext/syslog/lib/syslog/logger.rb, line 131
Logs a message
at the fatal (syslog err) log level, or logs the message returned from the block.
# File ext/syslog/lib/syslog/logger.rb, line 149
Logs a message
at the info (syslog info) log level, or logs the message returned from the block.
# File ext/syslog/lib/syslog/logger.rb, line 125
Logs a message
at the unknown (syslog alert) log level, or logs the message returned from the block.
# File ext/syslog/lib/syslog/logger.rb, line 143
Logs a message
at the warn (syslog notice) log level, or logs the message returned from the block.
Ruby Core © 1993–2017 Yukihiro Matsumoto
Licensed under the Ruby License.
Ruby Standard Library © contributors
Licensed under their own licenses.