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  • syslog/lib/syslog/logger.rb

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)'

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

formatter[RW]

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.

level[RW]

Log level for Logger compatibility.

Public Class Methods

make_methods(meth) click to toggle source

Builds a methods for level meth.

 
               # File syslog/lib/syslog/logger.rb, line 98
  def self.make_methods meth
    level = ::Logger.const_get(meth.upcase)
    eval <<-EOM, nil, __FILE__, __LINE__ + 1
      def #{meth}(message = nil, &block)
        add(#{level}, message, &block)
      end

      def #{meth}?
        @level <= #{level}
      end
    EOM
  end
new(program_name = 'ruby') click to toggle source

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.

Due to the way syslog works, only one program name may be chosen.

 
               # File syslog/lib/syslog/logger.rb, line 177
def initialize program_name = 'ruby'
  @level = ::Logger::DEBUG
  @formatter = Formatter.new

  @@syslog ||= Syslog.open(program_name)
end
syslog() click to toggle source

Returns the internal Syslog object that is initialized when the first instance is created.

 
               # File syslog/lib/syslog/logger.rb, line 84
def self.syslog
  @@syslog
end
syslog=(syslog) click to toggle source

Specifies the internal Syslog object to be used.

 
               # File syslog/lib/syslog/logger.rb, line 91
def self.syslog= syslog
  @@syslog = syslog
end

Public Instance Methods

add(severity, message = nil, progname = nil, &block) click to toggle source

Almost duplicates #add. progname is ignored.

 
               # File syslog/lib/syslog/logger.rb, line 187
def add severity, message = nil, progname = nil, &block
  severity ||= ::Logger::UNKNOWN
  @level <= severity and
    @@syslog.log LEVEL_MAP[severity], '%s', formatter.call(severity, Time.now, progname, (message || block.call))
  true
end
debug click to toggle source

Logs a message at the debug (syslog debug) log level, or logs the message returned from the block.

 
               # File syslog/lib/syslog/logger.rb, line 147
error click to toggle source

Logs a message at the error (syslog warning) log level, or logs the message returned from the block.

 
               # File syslog/lib/syslog/logger.rb, line 129
fatal click to toggle source

Logs a message at the fatal (syslog err) log level, or logs the message returned from the block.

 
               # File syslog/lib/syslog/logger.rb, line 123
info click to toggle source

Logs a message at the info (syslog info) log level, or logs the message returned from the block.

 
               # File syslog/lib/syslog/logger.rb, line 141
unknown click to toggle source

Logs a message at the unknown (syslog alert) log level, or logs the message returned from the block.

 
               # File syslog/lib/syslog/logger.rb, line 117
warn click to toggle source

Logs a message at the warn (syslog notice) log level, or logs the message returned from the block.

 
               # File syslog/lib/syslog/logger.rb, line 135