Extract OTZ images from a PG database and create them in the filesystem

extract_otz_images.rb

require 'rubygems'
require 'pg'
require 'FileUtils'

def write_file(data, path, name)
  return if data.nil? or data.empty?
  return if File.exists?("#{path}/#{name}")
  FileUtils.mkdir_p path
  f = File.new("#{path}/#{name}", 'w')
  f.write(PGconn.unescape_bytea(data))
  f.close
end

conn = PGconn.open(:dbname => 'otz')

puts "Fetching images ... "

images = conn.exec('select * from images')

puts "Extracting #{images.count} images ... "

images.each_with_index do |image, index|
  puts "  (#{index+1}/#{images.count}) .. Extracting #{image['img_file_name']}"
  path = "extracted_images/#{image['id']}"

  write_file(image['img_file'],        "#{path}/original", image['img_file_name'])
  write_file(image['img_medium_file'], "#{path}/medium", image['img_file_name'])
  write_file(image['img_thumb_file'],  "#{path}/thumb", image['img_file_name'])

end

puts "Complete."

conn.close