Grab version number from last merged GitHub pull request of a gitflow release branch

github-gitflow-jenkins-version-tag.sh

#!/bin/bash

TAG=$(git log --format=%s --merges -n 1 | cut -d '/' -f 3)

if ! [[ $TAG =~ ^[0-9]+\.[0-9]+\.[0-9]+$ ]]; then
    return 1
fi

echo "TAG = $TAG" > properties

# Used as a jenkins build step to grab the version number from the last
# merged GitHub pull request commit message.

# Assumes you are building on master and that you've just merged a gitflow
# release branch of the form, release/1.2.3 via GitHub pull request.

# Requires the EnvInject Plugin to read variables from the properties file. 
# The variable $TAG can then be used with the git publisher plugin to push the tag.