Rename files exported from L-Soft's LISTSERV software from XXX.LOGYYMM to XXX-YYYYMM.LOG

rename-listserv-log-files.rb

#!/usr/bin/env ruby

###
# Small script to rename files as exported from L-Soft's LISTSERV.
#
# Files are named with the month in the extension, e.g. SM-COP.LOG1410
# This renames them to be of the form SM-COP-2014-10.log
#
# Written by Eric Mill, eric.mill@gsa.gov. Public domain.
###

require 'fileutils'

# Take in directory full of .log[\d\d\d\d] files.
dir = ARGV[0]

# Prepend to 2-digit years. Update this value as the millenia pass.
century = "20"

# Rename them each in-place. This is a destructive action. Have a backup.
renamed = 0
Dir.glob("#{dir}/*").each do |path|
  name = File.basename(path)
  unless (matches = name.match(/^(.*?)(\.LOG)(\d\d)(\d\d)$/i))
    puts "NO MATCH: #{name}"
    next
  end

  listname = matches[1].upcase
  extension = matches[2].downcase
  year = "#{century}#{matches[3]}"
  month = matches[4]

  new_filename = "#{listname}-#{year}-#{month}#{extension}"

  puts "Renaming #{name} to #{new_filename}."
  FileUtils.mv(File.join(dir, name), File.join(dir, new_filename))

  renamed += 1
end

puts "Renamed #{renamed} files in-place."