git hook for sending email regarding migration changes

post-merge.rb

#!/usr/bin/env ruby
require 'pony'

def send_mail(to, from, message)
  Pony.mail({
    :to => to,
    :via => :smtp,
    :from => from,
    :subject => 'new migrations detected for master branch',
    :body => message,
    :via_options => {
      :address              => 'smtp.gmail.com',
      :port                 => '587',
      :enable_starttls_auto => true,
      :user_name            => ENV["EMAIL_USERNAME"],
      :password             => ENV["EMAIL_PASSWORD"],
      :authentication       => :plain, # :plain, :login, :cram_md5, no auth by default
    }
  })
end

branch = `git rev-parse --abbrev-ref HEAD`.strip

if branch == 'master'
  migration_diff = `git diff HEAD^ db/migrate`
  send_mail('email_to', 'email_from', migration_diff)
end