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Class: Logger::LogDevice

Relationships & Source Files
Super Chains via Extension / Inclusion / Inheritance
Instance Chain:
self, MonitorMixin, Period
Inherits: Object
Defined in: lib/logger.rb

Overview

Device used for logging messages.

Constant Summary

Period - Included

SiD

Class Method Summary

Instance Attribute Summary

Instance Method Summary

Constructor Details

.new(log = nil, opt = {}) ⇒ LogDevice

[ GitHub ]

  
# File 'lib/logger.rb', line 632

def initialize(log = nil, opt = {})
  @dev = @filename = @shift_age = @shift_size = nil
  mon_initialize
  set_dev(log)
  if @filename
    @shift_age = opt[:shift_age] || 7
    @shift_size = opt[:shift_size] || 1048576
    @next_rotate_time = next_rotate_time(Time.now, @shift_age) unless @shift_age.is_a?(Integer)
  end
end

Instance Attribute Details

#dev (readonly)

[ GitHub ]

  
# File 'lib/logger.rb', line 628

attr_reader :dev

#filename (readonly)

[ GitHub ]

  
# File 'lib/logger.rb', line 629

attr_reader :filename

Instance Method Details

#add_log_header(file) (private)

[ GitHub ]

  
# File 'lib/logger.rb', line 724

def add_log_header(file)
  file.write(
    "# Logfile created on %s by %s\n" % [Time.now.to_s, Logger::ProgName]
  ) if file.size == 0
end

#check_shift_log (private)

[ GitHub ]

  
# File 'lib/logger.rb', line 730

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)
      lock_shift_log { shift_log_age }
    end
  else
    now = Time.now
    if now >= @next_rotate_time
      @next_rotate_time = next_rotate_time(now, @shift_age)
      lock_shift_log { shift_log_period(previous_period_end(now, @shift_age)) }
    end
  end
end

#close

[ GitHub ]

  
# File 'lib/logger.rb', line 664

def close
  begin
    synchronize do
      @dev.close rescue nil
    end
  rescue Exception
    @dev.close rescue nil
  end
end

#create_logfile(filename) (private)

[ GitHub ]

  
# File 'lib/logger.rb', line 709

def create_logfile(filename)
  begin
    logdev = open(filename, (File::WRONLY | File::APPEND | File::CREAT | File::EXCL))
    logdev.flock(File::LOCK_EX)
    logdev.sync = true
    add_log_header(logdev)
    logdev.flock(File::LOCK_UN)
  rescue Errno::EEXIST
    # file is created by another process
    logdev = open_logfile(filename)
    logdev.sync = true
  end
  logdev
end

#lock_shift_log (private)

See additional method definition at line 746.

[ GitHub ]

  
# File 'lib/logger.rb', line 750

def lock_shift_log
  yield
end

#open_logfile(filename) (private)

[ GitHub ]

  
# File 'lib/logger.rb', line 701

def open_logfile(filename)
  begin
    open(filename, (File::WRONLY | File::APPEND))
  rescue Errno::ENOENT
    create_logfile(filename)
  end
end

#reopen(log = nil)

[ GitHub ]

  
# File 'lib/logger.rb', line 674

def reopen(log = nil)
  # reopen the same filename if no argument, do nothing for IO
  log ||= @filename if @filename
  if log
    synchronize do
      if @filename and @dev
        @dev.close rescue nil # close only file opened by Logger
        @filename = nil
      end
      set_dev(log)
    end
  end
  self
end

#set_dev(log) (private)

[ GitHub ]

  
# File 'lib/logger.rb', line 691

def set_dev(log)
  if log.respond_to?(:write) and log.respond_to?(:close)
    @dev = log
  else
    @dev = open_logfile(log)
    @dev.sync = true
    @filename = log
  end
end

#shift_log_age (private)

[ GitHub ]

  
# File 'lib/logger.rb', line 781

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 rescue nil
  File.rename("#{@filename}", "#{@filename}.0")
  @dev = create_logfile(@filename)
  return true
end

#shift_log_period(period_end) (private)

[ GitHub ]

  
# File 'lib/logger.rb', line 793

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)
  return true
end

#write(message)

[ GitHub ]

  
# File 'lib/logger.rb', line 643

def write(message)
  begin
    synchronize do
      if @shift_age and @dev.respond_to?(:stat)
        begin
          check_shift_log
        rescue
          warn("log shifting failed. #{$!}")
        end
      end
      begin
        @dev.write(message)
      rescue
        warn("log writing failed. #{$!}")
      end
    end
  rescue Exception => ignored
    warn("log writing failed. #{ignored}")
  end
end