Downloads FTP files with progress indicator...

ftp_downloader.rake

require 'yaml'
require 'net/ftp'
require 'net/ftp/list'
require 'fileutils'
require 'ruby-progressbar'
require 'zip'
require 'open3'

def download_with_progress(ftp, file)
  if not already_downloaded?(file)
    file_chunk = 512 * 1024
    pbar = ProgressBar.create(
      title: "downloading #{file.basename}", 
      total: file.filesize + file_chunk, 
      format: "%t |%B| (%p%% of #{file.filesize.to_human}) %e"
    )
    ftp.getbinaryfile(file.basename, File.join(downloaded_path, file.basename), file_chunk) { pbar.progress += file_chunk } 
    pbar.finish
    log "Downloaded #{file.basename}"
  end
end

desc "downloads any new *.zip files from ftp.bowker.com server"
task :download => [:environment] do
  log "Downloading new files..."
  ftp = Net::FTP.new
  ftp.connect config["bowker"]["server"]
  ftp.login config["bowker"]["userid"], config["bowker"]["password"]
  ftp.passive = true
  ftp.chdir config["bowker"]["path"] if config["bowker"]["path"]
  files = ftp.list('Poly*').map{|fn| Net::FTP::List.parse(fn)}.select{|s| s.file?}
  files.each{ |file| download_with_progress(ftp, file) }
  ftp.close
end