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Diffstat (limited to 'ruby_1_8_6/lib/logger.rb')
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diff --git a/ruby_1_8_6/lib/logger.rb b/ruby_1_8_6/lib/logger.rb new file mode 100644 index 0000000000..60e72424ad --- /dev/null +++ b/ruby_1_8_6/lib/logger.rb @@ -0,0 +1,703 @@ +# logger.rb - saimple logging utility +# Copyright (C) 2000-2003, 2005 NAKAMURA, Hiroshi <nakahiro@sarion.co.jp>. + +require 'monitor' + +# Simple logging utility. +# +# Author:: NAKAMURA, Hiroshi <nakahiro@sarion.co.jp> +# Documentation:: NAKAMURA, Hiroshi and Gavin Sinclair +# License:: +# You can redistribute it and/or modify it under the same terms of Ruby's +# license; either the dual license version in 2003, or any later version. +# Revision:: $Id$ +# +# == Description +# +# The Logger class provides a simple but sophisticated logging utility that +# anyone can use because it's included in the Ruby 1.8.x standard library. +# +# The HOWTOs below give a code-based overview of Logger's usage, but the basic +# concept is as follows. You create a Logger object (output to a file or +# elsewhere), and use it to log messages. The messages will have varying +# levels (+info+, +error+, etc), reflecting their varying importance. The +# levels, and their meanings, are: +# +# +FATAL+:: an unhandleable error that results in a program crash +# +ERROR+:: a handleable error condition +# +WARN+:: a warning +# +INFO+:: generic (useful) information about system operation +# +DEBUG+:: low-level information for developers +# +# So each message has a level, and the Logger itself has a level, which acts +# as a filter, so you can control the amount of information emitted from the +# logger without having to remove actual messages. +# +# For instance, in a production system, you may have your logger(s) set to +# +INFO+ (or +WARN+ if you don't want the log files growing large with +# repetitive information). When you are developing it, though, you probably +# want to know about the program's internal state, and would set them to +# +DEBUG+. +# +# === Example +# +# A simple example demonstrates the above explanation: +# +# log = Logger.new(STDOUT) +# log.level = Logger::WARN +# +# log.debug("Created logger") +# log.info("Program started") +# log.warn("Nothing to do!") +# +# begin +# File.each_line(path) do |line| +# unless line =~ /^(\w+) = (.*)$/ +# log.error("Line in wrong format: #{line}") +# end +# end +# rescue => err +# log.fatal("Caught exception; exiting") +# log.fatal(err) +# end +# +# Because the Logger's level is set to +WARN+, only the warning, error, and +# fatal messages are recorded. The debug and info messages are silently +# discarded. +# +# === Features +# +# There are several interesting features that Logger provides, like +# auto-rolling of log files, setting the format of log messages, and +# specifying a program name in conjunction with the message. The next section +# shows you how to achieve these things. +# +# +# == HOWTOs +# +# === How to create a logger +# +# The options below give you various choices, in more or less increasing +# complexity. +# +# 1. Create a logger which logs messages to STDERR/STDOUT. +# +# logger = Logger.new(STDERR) +# logger = Logger.new(STDOUT) +# +# 2. Create a logger for the file which has the specified name. +# +# logger = Logger.new('logfile.log') +# +# 3. Create a logger for the specified file. +# +# file = File.open('foo.log', File::WRONLY | File::APPEND) +# # To create new (and to remove old) logfile, add File::CREAT like; +# # file = open('foo.log', File::WRONLY | File::APPEND | File::CREAT) +# logger = Logger.new(file) +# +# 4. Create a logger which ages logfile once it reaches a certain size. Leave +# 10 "old log files" and each file is about 1,024,000 bytes. +# +# logger = Logger.new('foo.log', 10, 1024000) +# +# 5. Create a logger which ages logfile daily/weekly/monthly. +# +# logger = Logger.new('foo.log', 'daily') +# logger = Logger.new('foo.log', 'weekly') +# logger = Logger.new('foo.log', 'monthly') +# +# === How to log a message +# +# Notice the different methods (+fatal+, +error+, +info+) being used to log +# messages of various levels. Other methods in this family are +warn+ and +# +debug+. +add+ is used below to log a message of an arbitrary (perhaps +# dynamic) level. +# +# 1. Message in block. +# +# logger.fatal { "Argument 'foo' not given." } +# +# 2. Message as a string. +# +# logger.error "Argument #{ @foo } mismatch." +# +# 3. With progname. +# +# logger.info('initialize') { "Initializing..." } +# +# 4. With severity. +# +# logger.add(Logger::FATAL) { 'Fatal error!' } +# +# === How to close a logger +# +# logger.close +# +# === Setting severity threshold +# +# 1. Original interface. +# +# logger.sev_threshold = Logger::WARN +# +# 2. Log4r (somewhat) compatible interface. +# +# logger.level = Logger::INFO +# +# DEBUG < INFO < WARN < ERROR < FATAL < UNKNOWN +# +# +# == Format +# +# Log messages are rendered in the output stream in a certain format. The +# default format and a sample are shown below: +# +# Log format: +# SeverityID, [Date Time mSec #pid] SeverityLabel -- ProgName: message +# +# Log sample: +# I, [Wed Mar 03 02:34:24 JST 1999 895701 #19074] INFO -- Main: info. +# +# You may change the date and time format in this manner: +# +# logger.datetime_format = "%Y-%m-%d %H:%M:%S" +# # e.g. "2004-01-03 00:54:26" +# +# There is currently no supported way to change the overall format, but you may +# have some luck hacking the Format constant. +# + + +class Logger + VERSION = "1.2.6" + /: (\S+),v (\S+)/ =~ %q$Id$ + ProgName = "#{$1}/#{$2}" + + class Error < RuntimeError; end + class ShiftingError < Error; end + + # Logging severity. + module Severity + DEBUG = 0 + INFO = 1 + WARN = 2 + ERROR = 3 + FATAL = 4 + UNKNOWN = 5 + end + include Severity + + # Logging severity threshold (e.g. <tt>Logger::INFO</tt>). + attr_accessor :level + + # Logging program name. + attr_accessor :progname + + # Logging date-time format (string passed to +strftime+). + def datetime_format=(datetime_format) + @default_formatter.datetime_format = datetime_format + end + + def datetime_format + @default_formatter.datetime_format + end + + # Logging formatter. formatter#call is invoked with 4 arguments; severity, + # time, progname and msg for each log. Bear in mind that time is a Time and + # msg is an Object that user passed and it could not be a String. It is + # expected to return a logdev#write-able Object. Default formatter is used + # when no formatter is set. + attr_accessor :formatter + + alias sev_threshold level + alias sev_threshold= level= + + # Returns +true+ iff the current severity level allows for the printing of + # +DEBUG+ messages. + def debug?; @level <= DEBUG; end + + # Returns +true+ iff the current severity level allows for the printing of + # +INFO+ messages. + def info?; @level <= INFO; end + + # Returns +true+ iff the current severity level allows for the printing of + # +WARN+ messages. + def warn?; @level <= WARN; end + + # Returns +true+ iff the current severity level allows for the printing of + # +ERROR+ messages. + def error?; @level <= ERROR; end + + # Returns +true+ iff the current severity level allows for the printing of + # +FATAL+ messages. + def fatal?; @level <= FATAL; end + + # + # === Synopsis + # + # Logger.new(name, shift_age = 7, shift_size = 1048576) + # Logger.new(name, shift_age = 'weekly') + # + # === Args + # + # +logdev+:: + # The log device. This is a filename (String) or IO object (typically + # +STDOUT+, +STDERR+, or an open file). + # +shift_age+:: + # Number of old log files to keep, *or* frequency of rotation (+daily+, + # +weekly+ or +monthly+). + # +shift_size+:: + # Maximum logfile size (only applies when +shift_age+ is a number). + # + # === Description + # + # Create an instance. + # + def initialize(logdev, shift_age = 0, shift_size = 1048576) + @progname = nil + @level = DEBUG + @default_formatter = Formatter.new + @formatter = nil + @logdev = nil + if logdev + @logdev = LogDevice.new(logdev, :shift_age => shift_age, + :shift_size => shift_size) + end + end + + # + # === Synopsis + # + # Logger#add(severity, message = nil, progname = nil) { ... } + # + # === Args + # + # +severity+:: + # Severity. Constants are defined in Logger namespace: +DEBUG+, +INFO+, + # +WARN+, +ERROR+, +FATAL+, or +UNKNOWN+. + # +message+:: + # The log message. A String or Exception. + # +progname+:: + # Program name string. Can be omitted. Treated as a message if no +message+ and + # +block+ are given. + # +block+:: + # Can be omitted. Called to get a message string if +message+ is nil. + # + # === Return + # + # +true+ if successful, +false+ otherwise. + # + # When the given severity is not high enough (for this particular logger), log + # no message, and return +true+. + # + # === Description + # + # Log a message if the given severity is high enough. This is the generic + # logging method. Users will be more inclined to use #debug, #info, #warn, + # #error, and #fatal. + # + # <b>Message format</b>: +message+ can be any object, but it has to be + # converted to a String in order to log it. Generally, +inspect+ is used + # if the given object is not a String. + # A special case is an +Exception+ object, which will be printed in detail, + # including message, class, and backtrace. See #msg2str for the + # implementation if required. + # + # === Bugs + # + # * Logfile is not locked. + # * Append open does not need to lock file. + # * But on the OS which supports multi I/O, records possibly be mixed. + # + def add(severity, message = nil, progname = nil, &block) + severity ||= UNKNOWN + if @logdev.nil? or severity < @level + return true + end + progname ||= @progname + if message.nil? + if block_given? + message = yield + else + message = progname + progname = @progname + end + end + @logdev.write( + format_message(format_severity(severity), Time.now, progname, message)) + true + end + alias log add + + # + # Dump given message to the log device without any formatting. If no log + # device exists, return +nil+. + # + def <<(msg) + unless @logdev.nil? + @logdev.write(msg) + end + end + + # + # Log a +DEBUG+ message. + # + # See #info for more information. + # + def debug(progname = nil, &block) + add(DEBUG, nil, progname, &block) + end + + # + # Log an +INFO+ message. + # + # The message can come either from the +progname+ argument or the +block+. If + # both are provided, then the +block+ is used as the message, and +progname+ + # is used as the program name. + # + # === Examples + # + # logger.info("MainApp") { "Received connection from #{ip}" } + # # ... + # logger.info "Waiting for input from user" + # # ... + # logger.info { "User typed #{input}" } + # + # You'll probably stick to the second form above, unless you want to provide a + # program name (which you can do with <tt>Logger#progname=</tt> as well). + # + # === Return + # + # See #add. + # + def info(progname = nil, &block) + add(INFO, nil, progname, &block) + end + + # + # Log a +WARN+ message. + # + # See #info for more information. + # + def warn(progname = nil, &block) + add(WARN, nil, progname, &block) + end + + # + # Log an +ERROR+ message. + # + # See #info for more information. + # + def error(progname = nil, &block) + add(ERROR, nil, progname, &block) + end + + # + # Log a +FATAL+ message. + # + # See #info for more information. + # + def fatal(progname = nil, &block) + add(FATAL, nil, progname, &block) + end + + # + # Log an +UNKNOWN+ message. This will be printed no matter what the logger + # level. + # + # See #info for more information. + # + def unknown(progname = nil, &block) + add(UNKNOWN, nil, progname, &block) + end + + # + # Close the logging device. + # + def close + @logdev.close if @logdev + end + +private + + # Severity label for logging. (max 5 char) + SEV_LABEL = %w(DEBUG INFO WARN ERROR FATAL ANY) + + def format_severity(severity) + SEV_LABEL[severity] || 'ANY' + end + + def format_message(severity, datetime, progname, msg) + (@formatter || @default_formatter).call(severity, datetime, progname, msg) + end + + + class Formatter + Format = "%s, [%s#%d] %5s -- %s: %s\n" + + attr_accessor :datetime_format + + def initialize + @datetime_format = nil + end + + def call(severity, time, progname, msg) + Format % [severity[0..0], format_datetime(time), $$, severity, progname, + msg2str(msg)] + end + + private + + def format_datetime(time) + if @datetime_format.nil? + time.strftime("%Y-%m-%dT%H:%M:%S.") << "%06d " % time.usec + else + time.strftime(@datetime_format) + end + end + + def msg2str(msg) + case msg + when ::String + msg + when ::Exception + "#{ msg.message } (#{ msg.class })\n" << + (msg.backtrace || []).join("\n") + else + msg.inspect + end + end + end + + + class LogDevice + attr_reader :dev + attr_reader :filename + + class LogDeviceMutex + include MonitorMixin + end + + def initialize(log = nil, opt = {}) + @dev = @filename = @shift_age = @shift_size = nil + @mutex = LogDeviceMutex.new + if log.respond_to?(:write) and log.respond_to?(:close) + @dev = log + else + @dev = open_logfile(log) + @dev.sync = true + @filename = log + @shift_age = opt[:shift_age] || 7 + @shift_size = opt[:shift_size] || 1048576 + end + end + + def write(message) + @mutex.synchronize do + if @shift_age and @dev.respond_to?(:stat) + begin + check_shift_log + rescue + raise Logger::ShiftingError.new("Shifting failed. #{$!}") + end + end + @dev.write(message) + end + end + + def close + @mutex.synchronize do + @dev.close + end + end + + private + + def open_logfile(filename) + if (FileTest.exist?(filename)) + open(filename, (File::WRONLY | File::APPEND)) + else + create_logfile(filename) + end + end + + def create_logfile(filename) + logdev = open(filename, (File::WRONLY | File::APPEND | File::CREAT)) + logdev.sync = true + add_log_header(logdev) + logdev + end + + def add_log_header(file) + file.write( + "# Logfile created on %s by %s\n" % [Time.now.to_s, Logger::ProgName] + ) + end + + SiD = 24 * 60 * 60 + + def check_shift_log + if @shift_age.is_a?(Integer) + # Note: always returns false if '0'. + if @filename && (@shift_age > 0) && (@dev.stat.size > @shift_size) + shift_log_age + end + else + now = Time.now + if @dev.stat.mtime <= previous_period_end(now) + shift_log_period(now) + end + end + end + + def shift_log_age + (@shift_age-3).downto(0) do |i| + if FileTest.exist?("#{@filename}.#{i}") + File.rename("#{@filename}.#{i}", "#{@filename}.#{i+1}") + end + end + @dev.close + File.rename("#{@filename}", "#{@filename}.0") + @dev = create_logfile(@filename) + return true + end + + def shift_log_period(now) + postfix = previous_period_end(now).strftime("%Y%m%d") # YYYYMMDD + age_file = "#{@filename}.#{postfix}" + if FileTest.exist?(age_file) + raise RuntimeError.new("'#{ age_file }' already exists.") + end + @dev.close + File.rename("#{@filename}", age_file) + @dev = create_logfile(@filename) + return true + end + + def previous_period_end(now) + case @shift_age + when /^daily$/ + eod(now - 1 * SiD) + when /^weekly$/ + eod(now - ((now.wday + 1) * SiD)) + when /^monthly$/ + eod(now - now.mday * SiD) + else + now + end + end + + def eod(t) + Time.mktime(t.year, t.month, t.mday, 23, 59, 59) + end + end + + + # + # == Description + # + # Application -- Add logging support to your application. + # + # == Usage + # + # 1. Define your application class as a sub-class of this class. + # 2. Override 'run' method in your class to do many things. + # 3. Instantiate it and invoke 'start'. + # + # == Example + # + # class FooApp < Application + # def initialize(foo_app, application_specific, arguments) + # super('FooApp') # Name of the application. + # end + # + # def run + # ... + # log(WARN, 'warning', 'my_method1') + # ... + # @log.error('my_method2') { 'Error!' } + # ... + # end + # end + # + # status = FooApp.new(....).start + # + class Application + include Logger::Severity + + attr_reader :appname + attr_reader :logdev + + # + # == Synopsis + # + # Application.new(appname = '') + # + # == Args + # + # +appname+:: Name of the application. + # + # == Description + # + # Create an instance. Log device is +STDERR+ by default. This can be + # changed with #set_log. + # + def initialize(appname = nil) + @appname = appname + @log = Logger.new(STDERR) + @log.progname = @appname + @level = @log.level + end + + # + # Start the application. Return the status code. + # + def start + status = -1 + begin + log(INFO, "Start of #{ @appname }.") + status = run + rescue + log(FATAL, "Detected an exception. Stopping ... #{$!} (#{$!.class})\n" << $@.join("\n")) + ensure + log(INFO, "End of #{ @appname }. (status: #{ status.to_s })") + end + status + end + + # + # Sets the log device for this application. See the class Logger for an + # explanation of the arguments. + # + def set_log(logdev, shift_age = 0, shift_size = 1024000) + @log = Logger.new(logdev, shift_age, shift_size) + @log.progname = @appname + @log.level = @level + end + + def log=(logdev) + set_log(logdev) + end + + # + # Set the logging threshold, just like <tt>Logger#level=</tt>. + # + def level=(level) + @level = level + @log.level = @level + end + + # + # See Logger#add. This application's +appname+ is used. + # + def log(severity, message = nil, &block) + @log.add(severity, message, @appname, &block) if @log + end + + private + + def run + raise RuntimeError.new('Method run must be defined in the derived class.') + end + end +end |