A ruby gem to look up the DMARC policy of any email service provider
To look up the DMARC policy of an email service provider, say yahoo.com, use
dmarc_inspector = DMARCInspector.new('yahoo.com')
dmarc_inspector.receiver_policy
# => :reject
If an email service provider doesn't have a DMARC policy, the DMARCInspector#receiver_policy
method returns :none
See this spec for more examples
Add dmarc_inspector to your app's Gemfile
gem 'dmarc_inspector'
and run
bundle install
Wikipedia's article on DMARC and Postmark's post on DMARC are great articles to quickly understand DMARC.
To understand DMARC in entirety, I highly recommend reading RFC 7489. Its relatively short compared to most RFCs.