Cdigits

Cdigits implements Luhn N algorithm.

usage	N	valid characters	example
Cdigit::Luhn.number	10	0 to 9	8217161655
Cdigit::Luhn.hex	16	0 to 9 and a to f	e780dcc9c9
Cdigit::Luhn.alphanumeric	36	0 to 9 and a to z	6lgoybfzvr
Cdigit::Luhn.easy	30	0 to 9 and A to Z without D / I / M / O / Q / Z	U1B3J0SCG8

Also, you can generate code in any format using placeholder.

example:

Cdigits::Luhn.number 'CA##-####-####-###?' # => "CA63-6485-2316-2675"
Cdigits::Luhn.number '2020-01##-####-###?' # => "2020-0173-1935-2569"

Installation

Add this line to your application's Gemfile:

gem 'cdigits'

And then execute:

$ bundle install

Or install it yourself as:

$ gem install cdigits

Usage

Generate code

placeholder = 'CA##-####-####-###?'
Cdigits::Luhn.number
# => "1638302982"
Cdigits::Luhn.number placeholder
# => "CA16-5930-2060-1262"
Cdigits::Luhn.hex
# => "2b69307483"
Cdigits::Luhn.hex placeholder
# => "CA1e-fe6c-1c04-9a28"
Cdigits::Luhn.alphanumeric
# => "th5h7fewjl"
Cdigits::Luhn.alphanumeric placeholder
# => "CAwf-mfkx-ncsv-odl2"
Cdigits::Luhn.easy
# => "NWK036TN1R"
Cdigits::Luhn.easy placeholder
# => "CAPY-SHHN-U55U-9PG7"

Special chars in placeholder

• + ... non-zero random number (1 to modulus)
• # ... random number (0 to modulus)
• ? ... check digit

Validate code

Cdigits::Luhn.number? '6907562414'
# => true
Cdigits::Luhn.hex? '2c14a42508'
# => true
Cdigits::Luhn.alphanumeric? 'yrkxeh4eie'
# => true
Cdigits::Luhn.easy? '16TPF8RETL'
# => true

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/kengos/cdigits. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the code of conduct.

License

The gem is available as open source under the terms of the MIT License.

Code of Conduct

Everyone interacting in the Cdigits project's codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.