Simple FTP mirroring tool in Ruby

mirrorer.rb

#!/usr/bin/ruby
require 'net/ftp'
require 'net/http'
require 'fileutils'

class String
    def to_l(srcl,dstl)
    val = gsub(/(["'\&\(\)])/) { "\\" + $1 }
    `echo #{val} |iconv -f #{srcl} -t #{dstl}`.sub(/\n/,"")
    end
end

class Logger
    def initialize(verbose,file)
	@verbose = verbose
	@log = File.open(file,'a') if file
    end

    def verbose(msg, level = 0)
	if @verbose >= level
	    puts msg
	    if @log
		@log.write(msg + "\n")
		@log.flush 
	    end
        end
    end

    def error(msg)
	verbose('Exiting: ' + msg)
	exit
    end
end

class Net::FTP
    attr_writer :log, :simulate
    def mirror(folder)
	@log.verbose("Curdir #{FileUtils.pwd}\nRemdir #{pwd}",2)
	name = folder.to_l("cp1251","utf-8")
	unless @simulate then
	    begin
		FileUtils.cd(name)
	    rescue Errno::ENOENT
		FileUtils.makedirs(name)
		retry
	    end
	end
	@log.verbose("Folder #{name}",1)
	chdir(folder) 
	list.each {|line|
	    @log.verbose("Line #{line}",3)
	    line =~ /^([d-])[rwx-]{1,9} +\d+ \w+ +\w+ +(\d+) (\w{3} +/
			/\d{1,2} +[\d:]+) (.*)$/
	    next if $4 == "." or $4 == ".."
	    if $1 == "d" then
		@log.verbose("Down to folder #{$4}",2)
		mirror($4) 
	    else
		file = $4.to_l("cp1251","utf-8")
		@log.verbose("File sizes: local = #{File.size?(file)}, "
		    "remote = #{$2.to_i} ",2)
		if !@simulate and File.size?(file) == $2.to_i then
		    @log.verbose("File #{file} is exist and the same "
			"as the remote: not downloading",1)
		    next;
		end
		@log.verbose("Downloading file #{file}",1)
		begin
		    getbinaryfile($4, $4.to_l("cp1251","utf-8"), 1024) 
			unless @simulate
		rescue Errno::EEXIST
		    next
		end
	    end
	}
	FileUtils.cd("..")
	chdir("..")
    end
end

class App
    def initialize
	log = '/local/var/log/mirrorer.log'
	@log = Logger.new(3,log)
	p = `ps aux`
	c = 0
	val = $0.gsub(/.*\//,"")
	while p =~ /ruby.*#{val}/o
	    c = c + 1 
	    p = p.sub(/#{val}/o, "")
	end 
	@log.error("Duplex run") if c > 1
    end
end

class Mirrorer < App
    def initialize(*args)
	    super
	    sites = '/local/etc/sites'
	    #init vars
	    @simulate = nil
	    @simulate = true
	    @root_folder = "/local/share/mirrors"
	    begin 
	        @sites = IO.read(sites);
	    rescue Errno::ENOENT
	        @log.error("File #{sites} doesn't exist. Nothing to mirror")
	    end
	    #change to specified path
	    retries = 0
	    begin
	        FileUtils.cd(@root_folder)
	    rescue Errno::ENOENT
	        begin
		    FileUtils.mkdir(@root_folder)
	        rescue Errno::EACCES
		    @log.error("Can't create the specfied mirror root folder"
		            " '#{@root_folder}'")
	        end
	        retry
	    end
    end

    def mirror
	    @sites.each { |line|
	        FileUtils.cd(@root_folder)
	        next if line =~ /#.*/
	        @log.verbose("Reading the new line",2)
	        if line =~ /^(.*) +(.*?)$/ then
		        site = $1
		        folder_path = $2
	        else
		        site = line
	        end
	        @log.error "Wrong site name, please check" 
		    if (site.gsub(/%(..)/) {|s|
		            $1.hex.chr } !~ /^ *(ftp|http):\/\/(?:(.*?)\/)?
		            (?:(.*)\/)*(?:(.*)\/?)?$/)
	        ftp_addr = $2
	        folder_path = $2 + '/' + $3.to_s.to_l("cp1251","utf-8") if !folder_path
	        remote_dir = $3
	        folder = $4
	        @log.verbose("Connecting to site #{ftp_addr}",0)
	        @log.verbose("Site = #{ftp_addr.to_l("cp1251","utf-8")}, "
		            "folder = #{folder_path}, folder = "
		            "#{folder.to_l("cp1251","utf-8")}",2)
	        @log.verbose("#{ftp_addr}, #{folder_path}, #{remote_dir}, "
		            "#{folder}",2)
	        begin
		        ftp = Net::FTP.new ftp_addr.gsub(/\//,"")
	        rescue Errno::ECONNREFUSED
		        @log.error "Connection to the server #{ftp_addr.gsub(/\//,"")}"
		                " is refused"
	        end
	        ftp.log = @log
	        ftp.simulate = @simulate
	        begin
	    	    ftp.login
	        rescue Net::FTPTempError
		        @log.verbose('421 Too many users - please try again later',0)
		        next
	        end
	        begin
		        FileUtils.cd folder_path
	        rescue Errno::ENOENT
		        begin
		            FileUtils.makedirs folder_path
		        rescue Errno::ENOACC
		            @log.error "Can't create target directories"
		        end
		        retry
	        end
	        ftp.chdir(remote_dir) if remote_dir
	        ftp.mirror(folder)
	        ftp.close
	    }
    end
end


mirrorer = Mirrorer.new
mirrorer.mirror