mail_provider

https://github.com/nikhgupta/mail_provider

Smartly check whether a given email/domain belongs to a free or disposable mail provider. There are hundreds of lists available in Github repositories or Gists that list various free and disposable email providers. This gem downloads a bunch of these scripts (pre-configured URLs) and parses them to count votes against each domain in the list. We, then, create a Trie structure to efficiently query this data with a given domain or email. For each query, you get back a number specifying how many sources are claiming that the domain is a free or disposable email provider.