git_watch.rb

#!/usr/bin/env ruby
#--
#    Name    : git_watch.rb
#    Author  : Jerod Santo
#    Contact : "moc.liamg@otnas.dorej".reverse
#    Date    : 2008 October 14
#    About   : Checks a git repository for changes and emails provided email
#              address if changes have been made. Schedule with cron.
#--

require 'net/smtp'
require 'fileutils'

SEND_TO = "jerod.santo@gmail.com"

def send_email(to,opts={})
  opts[:server]      ||= 'localhost'
  opts[:from]        ||= 'git@example.com'
  opts[:from_alias]  ||= 'Git Watch'
  opts[:subject]     ||= "A repo has changed!"
  opts[:body]        ||= "A repo has changed!"

  msg = <<END_OF_MESSAGE
From: #{opts[:from_alias]} <#{opts[:from]}>
To: <#{to}>
Subject: #{opts[:subject]}

#{opts[:body]}
END_OF_MESSAGE

  Net::SMTP.start(opts[:server]) do |smtp|
    smtp.send_message msg, opts[:from], to
  end
end

unless ARGV.length == 1
  puts "Usage: #{__FILE__} [path to repo with .git directory]"
  exit
end

path = File.expand_path(ARGV.first)
unless Dir.entries(path).include? ".git"
  puts "Sorry, but there's no git repository in #{path}"
  exit
end

FileUtils.cd path
result = `git status`
unless result =~ /working directory clean/
  message  = "Host: #{`hostname`}\n"
  message += "Repository:  #{path}\n"
  message += "Checked at: #{Time.now}\n"
  message += "Change log:\n\n"
  message += result
  send_email SEND_TO, :body  => message
end