update githook

update.rb

#!/usr/bin/env ruby    
    
# Git update hook
# Policy enforcement
# Do not validate merge commits
# Commit message must be in format:
#
# 'T1234
# awesome commit message'
#
$refname = ARGV[0]    
$oldrev = ARGV[1]    
$newrev = ARGV[2]    
$user = ENV['USER']    

puts "Enforcing Policies... \n(#{$refname}) (#{$oldrev[0,6]}) (#{$newrev[0,6]})"

# enforced custom commit message format
def check_message_format
  return if $refname =~ /^refs\/tags\/.*$/
  regex = /^\n*(T|t)(\d+)\n{1,}.+$/ 
  missed_revs = `git rev-list #{$oldrev}..#{$newrev}`.split("\n")
  missed_revs.each do |rev|
    message = `git cat-file commit #{rev} | sed '1,/^$/d'`
    next if message =~ /Merge branch|Reverted/
    if message !~ regex
      puts "[POLICY] Your message is not formatted correctly"
      exit 1
    end 
  end 
end
check_message_format