A ruby gem to check if the owner of a given email address or website is working for THE MAN (a.k.a verifies government domains). It will also provide you with metadata about the domain, such as the country, state, city, or agency, where applicable. It does this by leveraging the power of Naughty or Nice, the Public Suffix List, and the associated Ruby Gem.

You could theoretically use regex, but either you'll get a bunch of false positives, or your regex will be insanely complicated. gov.uk, may be valid, for example, but gov.fr is not (it's gouv.fr, for what it's worth). The solution? Use Public Suffix to verify that it's a valid public domain, then maintain a crowd-sourced sub-list of known global government and military domains. It should cover all US and international, government and military domains for both email and website verification.

See a domains that's missing or one that shouldn't be there? We'd love you to contribute.

Gman is a Ruby gem, so you'll need a little Ruby-fu to get it working. Simply

gem install gman

Or add this to your Gemfile before doing a bundle install:

gem 'gman'

Gman.valid? "[email protected]" #=> true
Gman.valid? "[email protected]" #=> false

Gman.valid? "http://foo.bar.gov" #=> true
Gman.valid? "foo.bar.gov"        #=> true
Gman.valid? "foo.gov"            #=> true
Gman.valid? "foo.biz"            #=> false

domain = Gman.new "whitehouse.gov"
domain.type     #=> :federal
domain.federal? #=> true
domain.state?   #=> false
domain.city?    #=> false
domain.county?  #=> false

domain = Gman.new "illinois.gov"
domain.state #=> "IL"
domain.city  #=> "springfield"

domain = Gman.new "whitehouse.gov"
domain.agency   #=> "Executive Office of the President"

domain = Gman.new "whitehouse.gov" #=> #<Gman domain="whitehouse.gov" valid=true>
domain.country.name                #=> "United States"
domain.country.alpha2              #=> "US"
domain.country.alpha3              #=> "USA"
domain.country.currency            #=> "USD"
domain.country.calling_code        #=> " 1"

Gman.new("foo.gov.kp").sanctioned? #=> true

$ gman whitehouse.gov
Domain  : whitehouse.gov
Valid government domain
Type    : federal
Country : United States
State   : DC
City    : Washington
Agency  : Executive Office of the President

The command line tool will accept any domain-like string (email, url, etc.)

$ gman [email protected]
Domain  : illinois.gov
Valid government domain
Type    : state
Country : United States
State   : IL
City    : Springfield

Filters newline-separated email addresses from stdin. Example usage:

$ gman_filter < path/to/list/of/addresses.txt

Contributions welcome! Please see the contribution guidelines for code contributions or for details on how to add, update, or delete government domains.

Heavily inspired by swot. Thanks @leereilly!