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+require 'syslog'
+require '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 Syslog::Logger.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.
+
+class Syslog::Logger
+
+ ##
+ # The version of Syslog::Logger you are using.
+
+ VERSION = '2.0'
+
+ ##
+ # 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).
+
+ LEVEL_MAP = {
+ ::Logger::UNKNOWN => Syslog::LOG_ALERT,
+ ::Logger::FATAL => Syslog::LOG_ERR,
+ ::Logger::ERROR => Syslog::LOG_WARNING,
+ ::Logger::WARN => Syslog::LOG_NOTICE,
+ ::Logger::INFO => Syslog::LOG_INFO,
+ ::Logger::DEBUG => Syslog::LOG_DEBUG,
+ }
+
+ ##
+ # Returns the internal Syslog object that is initialized when the
+ # first instance is created.
+
+ def self.syslog
+ @@syslog
+ end
+
+ ##
+ # Specifies the internal Syslog object to be used.
+
+ def self.syslog= syslog
+ @@syslog = syslog
+ end
+
+ ##
+ # Builds a methods for level +meth+.
+
+ 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
+
+ ##
+ # :method: unknown
+ #
+ # Logs a +message+ at the unknown (syslog alert) log level, or logs the
+ # message returned from the block.
+
+ ##
+ # :method: fatal
+ #
+ # Logs a +message+ at the fatal (syslog err) log level, or logs the message
+ # returned from the block.
+
+ ##
+ # :method: error
+ #
+ # Logs a +message+ at the error (syslog warning) log level, or logs the
+ # message returned from the block.
+
+ ##
+ # :method: warn
+ #
+ # Logs a +message+ at the warn (syslog notice) log level, or logs the
+ # message returned from the block.
+
+ ##
+ # :method: info
+ #
+ # Logs a +message+ at the info (syslog info) log level, or logs the message
+ # returned from the block.
+
+ ##
+ # :method: debug
+ #
+ # Logs a +message+ at the debug (syslog debug) log level, or logs the
+ # message returned from the block.
+
+ Logger::Severity::constants.each do |severity|
+ make_methods severity.downcase
+ end
+
+ ##
+ # Log level for Logger compatibility.
+
+ attr_accessor :level
+
+ ##
+ # 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.
+
+ def initialize program_name = 'ruby'
+ @level = ::Logger::DEBUG
+
+ @@syslog ||= Syslog.open(program_name)
+ end
+
+ ##
+ # Almost duplicates Logger#add. +progname+ is ignored.
+
+ def add severity, message = nil, progname = nil, &block
+ severity ||= ::Logger::UNKNOWN
+ @level <= severity and
+ @@syslog.log LEVEL_MAP[severity], '%s', clean(message || block.call)
+ true
+ end
+
+ private
+
+ ##
+ # Clean up messages so they're nice and pretty.
+
+ def clean message
+ message = message.to_s.strip
+ message.gsub!(/\e\[[0-9;]*m/, '') # remove useless ansi color codes
+ return message
+ end
+
+end
+