File_column ruby legacy file-upload plugin

file_column_ruby.rb

##
# If you encountered a problem like this:
#   Errno::EMLINK: Too many links ...releases/20110811111351/public/document/file/51159
# Most likely it is caused by the limitations of your Linux filesystem - 
# a directory can only have a certain number of sub-directories.
#
# http://blog.zachwaugh.com/post/309921185/ext3-filesystem-sub-directory-limit
#

##
# Solution:
#   /public/document/file/149/file_name.ext => 
#   /public/document/file/1/4/9/file_name.ext
#
require 'fileutils'

Dir['*'].each do |dir_name|
  if dir_name.length > 1
    rel_path = dir_name.scan(/\d/).join('/')
    FileUtils.mkdir_p(rel_path)
    FileUtils.mv Dir.glob(dir_name + '/*.*'), rel_path
    FileUtils.rm_rf dir_name
    p rel_path
  end
end

##
# Patch for legacy ruby file-upload plugin "file_column"
#
def after_save
  super
  # we have a newly uploaded image, move it to the correct location
  file = clone_as PermanentUploadedFile
  
  # PATCH HERE:
  FileUtils.mkdir_p file.instance_eval { @dir }.to_s

  file.move_from(File.join(tmp_base_dir, @tmp_dir), @just_uploaded)
  # delete temporary files
  delete_files
  # replace with the new PermanentUploadedFile object
  file
end

def relative_path_prefix
  raise RuntimeError.new("Trying to access file_column, but primary key got lost.") if @instance.id.to_s.empty?

  # PATCH HERE:
  @instance.id.to_s.scan(/\d/).join('/')
end