Example Rakefile for managing photos

gistfile1.txt

# if you have a directory of files that look like:
# 2015-03-21 11.23.39.jpg 
# 2015-04-15 09.55.20.jpg
# 2015-03-21 11.23.42.jpg
# 2015-05-12 13.14.59.png 
#
# this Rakefile will move all the files into subdirectories for year/month

task :default do |task|
  file_list = FileList['*.jpg', '*.png']

  file_list.each do |file|
    year = file[/^\d{4}/]
    month = file[/(?<=^\d{4}-)\d{2}/]
    directory = File.join year, month

    mkdir_p directory
    mv file, directory
  end
end