prepare-commit-msg

#!/usr/bin/env groovy

// Example prepare-commit-msg hook written in groovy
// (c) 2016 Brent Laster

import static java.lang.System.*

def argc = this.args.size()
def commitmsg_file_path, commit_type, commit_sha1

commitmsg_file_path = this.args[0]

// Get explicit commit type if passed
if (argc > 1) 
       commit_type = this.args[1]
else
    commit_type = ''

if (argc > 2)
    commit_sha1 = this.args[2]
else
    commit_sha1 = ''

// See if we have user-defined message set
def iuo_msg = ["git", "config", "user.msg"].execute()
iuo_msg.waitFor()
def config_rc = iuo_msg.exitValue()

// If we don't have the configuration value set, then abort
if (config_rc!=0)
{ 
       println "Configuration setting not found for user.msg."
       println "Aborting commit!"
       exit 1
}
def msg = iuo_msg.text

// Read in an existing commit message
def File commit_file = new File(commitmsg_file_path)

// If the commit message already contains the value, then just continue
if (commit_file.text.find(msg)) 
{
    println("Commit message already contains $msg - proceeding...")
    exit 0
}

// Determine the branch
def output_branch = ["git", "symbolic-ref", "--short", "HEAD"].execute()
output_branch.waitFor()
def current_branch = output_branch.text.trim()

// If it matches the desired branch names, then append the custom message
if  (current_branch.matches(/^master$|^(prod|ship).*$/))
{
       println "Current branch $current_branch is a production branch."
       commit_file.append(msg)
}
exit 0