I was getting the following error:

Error: uninitialized constant MysqlCompat::MysqlRes

Then I uninstalled the mysql gem and tried to install it again only to get the following error:

Building native extensions. This could take a while...
ERROR: While executing gem ... (Gem::Installer::ExtensionBuildError)
ERROR: Failed to build gem native extension.

Then I issued the following command:

sudo apt-get install libmysqlclient-dev

and then installed mysql gem and it installed with no problems. Finally, rake db:migrate worked again.

First you need to install the gem:

sudo gem install pabarcode

then the example in the previous post needs to change so as it uses the gem instead of the plain Ruby file:

require "rubygems"
require "pabarcode"

include PAbarcode

file = File.open("apog.txt")

file.each do |line|
  bc = line.slice(0..11)
  bc13 = Barcode.new(bc).get_ean_13
  puts bc13 + line.slice(12..line.length)
end

file.close

Yesterday, a colleague of mine asked me to take as input a file with 12 characters long barcodes and add a check digit assuming the barcodes are EAN13. I decided to do it and also start maintaining a set of barcode helper classes written in Ruby. I haven’t created a gem yet, cause the functionality is … lets say limited , but I plan to do so later.

You can go to

http://github.com/amiridis/rbarcode

and just download the barcode.rb file.

Here is how I used the barcode.rb file in order to transform the file:

require "barcode"

file = File.open("apog.txt")

file.each do |line|
  bc = line.slice(0..11)
  bc13 = Barcode.new(bc).get_ean_13
  puts bc13 + line.slice(12..line.length)
end

file.close

The file had the following format:

520532435284;1;09
520532435285;1;09
520532463580;1;09

and for the three lines above it produces:

5205324352841;1;09
5205324352858;1;09
5205324635807;1;09

Update: I have changed this project to a gem. You can read about it in my PAbarcode gem post.