230 lines
7.2 KiB
Ruby
230 lines
7.2 KiB
Ruby
# logger.rb - simple logging utility
|
||
# Copyright (C) 2000-2003, 2005, 2008, 2011 NAKAMURA, Hiroshi <nahi@ruby-lang.org>.
|
||
#
|
||
# 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: logger.rb 31641 2011-05-19 00:07:25Z nobu $
|
||
#
|
||
# A simple system for logging messages. See Logger for more documentation.
|
||
|
||
require 'monitor'
|
||
require 'fileutils'
|
||
# == Description
|
||
#
|
||
# The Logger class provides a simple but sophisticated logging utility that
|
||
# you can use to output messages.
|
||
#
|
||
# The messages have associated levels, such as +INFO+ or +ERROR+ that indicate
|
||
# their importance. You can then give the Logger a level, and only messages
|
||
# at that level of higher will be printed.
|
||
#
|
||
# The levels 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
|
||
#
|
||
# For instance, in a production system, you may have your Logger set to
|
||
# +INFO+ or even +WARN+
|
||
# When you are developing the system, however, you probably
|
||
# want to know about the program's internal state, and would set the Logger to
|
||
# +DEBUG+.
|
||
#
|
||
# *Note*: Logger does not escape or sanitize any messages passed to it.
|
||
# Developers should be aware of when potentially malicious data (user-input)
|
||
# is passed to Logger, and manually escape the untrusted data:
|
||
#
|
||
# logger.info("User-input: #{input.dump}")
|
||
# logger.info("User-input: %p" % input)
|
||
#
|
||
# You can use #formatter= for escaping all data.
|
||
#
|
||
# original_formatter = Logger::Formatter.new
|
||
# logger.formatter = proc { |severity, datetime, progname, msg|
|
||
# original_formatter.call(severity, datetime, progname, msg.dump)
|
||
# }
|
||
# logger.info(input)
|
||
#
|
||
# === Example
|
||
#
|
||
# This creates a logger to the standard output stream, with a level of +WARN+
|
||
#
|
||
# 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!' }
|
||
#
|
||
# The block form allows you to create potentially complex log messages,
|
||
# but to delay their evaluation until and unless the message is
|
||
# logged. For example, if we have the following:
|
||
#
|
||
# logger.debug { "This is a " + potentially + " expensive operation" }
|
||
#
|
||
# If the logger's level is +INFO+ or higher, no debug messages will be logged,
|
||
# and the entire block will not even be evaluated. Compare to this:
|
||
#
|
||
# logger.debug("This is a " + potentially + " expensive operation")
|
||
#
|
||
# Here, the string concatenation is done every time, even if the log
|
||
# level is not set to show the debug message.
|
||
#
|
||
# === 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 by
|
||
# default. 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 via #datetime_format=
|
||
#
|
||
# logger.datetime_format = "%Y-%m-%d %H:%M:%S"
|
||
# # e.g. "2004-01-03 00:54:26"
|
||
#
|
||
# Or, you may change the overall format with #formatter= method.
|
||
#
|
||
# logger.formatter = proc do |severity, datetime, progname, msg|
|
||
# "#{datetime}: #{msg}\n"
|
||
# end
|
||
# # e.g. "Thu Sep 22 08:51:08 GMT+9:00 2005: hello world"
|
||
#
|
||
# class Logger
|
||
# #具体内容请看https://bugs.ruby-lang.org/issues/7303
|
||
# # Device used for logging messages.
|
||
# class LogDevice
|
||
# def shift_log_period(period_end)
|
||
# postfix = period_end.strftime("%Y%m%d") # YYYYMMDD
|
||
# age_file = "#{@filename}.#{postfix}"
|
||
# if FileTest.exist?(age_file)
|
||
# # try to avoid filename crash caused by Timestamp change.
|
||
# idx = 0
|
||
# # .99 can be overridden; avoid too much file search with 'loop do'
|
||
# while idx < 100
|
||
# idx += 1
|
||
# age_file = "#{@filename}.#{postfix}.#{idx}"
|
||
# break unless FileTest.exist?(age_file)
|
||
# end
|
||
# end
|
||
# # @dev.close rescue nil
|
||
# # File.rename("#{@filename}", age_file)
|
||
# # @dev = create_logfile(@filename)
|
||
# #覆盖原来lib库的方法,将上边三行删除,增加下边两行
|
||
# FileUtils.cp(@filename, age_file)
|
||
# reset_logfile(@dev) # see below for this new method return true
|
||
# return true
|
||
# end
|
||
# #打开原来lib库,新增一个方法
|
||
# def reset_logfile(logdev)
|
||
# logdev.truncate( 0 )
|
||
# logdev.sync = true
|
||
# add_log_header(logdev)
|
||
# end
|
||
# end
|
||
# end
|