VldMail is a ruby wrapper for the C language libvldmail email validation library. I built it to explore the ruby C API,to get my hands dirty building a ruby C gem, and to document how to do this for other ruby developers who might be curious about building C extensions.

N.B.: This is UNTESTED, ALPHA QUALITY CODE. Sorry for shouting. But if you landed here, because you want to use libvldmail in your ruby app, the author of libvldmail suggests using SWIG. Do that.

tl;dr Know ruby. Learn C. Read over some of the listed resources. Read the commits in this repo from initial commit to HEAD.

Prerequisites: You should know ruby well. Basic familiarity with C is sufficient to get started. If you have no prior exposure to C, just start with K&R, 2nd ed. It's one of those rare programming books that's both useful and a good read.

Here are some resources I found helpful:

• Creating extension libraries for Ruby
• Writing Ruby C extensions: Part 1
• Writing Ruby C Extensions: Part 2
• Writing your very own Ruby extension with C
• Awesome C

Start at ruby-lang.org and read for a high-level understanding. Then try the blog posts. Then go back to ruby-lang.org to answer your questions. Awesome C is where I found libvldmail. Maybe you'll find something there to play with.

Then there's this project: I wrote each commit to document the process of making the gem -- sort of a really slow motion live-coding presentation. (And like any live-coding, this one includes a few missteps....) So head over to Commits and work from the bottom up.

Yeah, this could probably be a blog post, but I haven't finished rewriting my blog engine yet. ;-)

Add this line to your application's Gemfile:

gem 'vldmail-rb', git: 'https://github.com/jlcapps/vldmail-rb.git', branch: 'master'

And then execute:

$ bundle install

Or follow instructions beneath Development.

require 'vldmail'

validation = VldMail::Validation.new('[email protected]')
validation.email
  => '[email protected]'
validation.success?
  => true
validation.message
  => ''
validation = VldMail::Validation.new('foo@example@com')
validation.success?
  => false
validation.message
  => 'One @ is more than enough.'

After checking out the repo, run bin/setup to install dependencies. Then, run rake test 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.

The gem is available as open source under the terms of the MIT-0 License.