Groovy/Jenkins function to return the ID number of last successful build for a specific Jenkins job

get-last-successful-build-no.groovy

#!/usr/bin/env groovy

/**
 * Gets last successful build number
 * @author thabet.amer@gmail.com
 * @since Jenkins 2.204.1
 * @param String job name
 * @return String number of build number
 *
 */

import jenkins.model.Jenkins

def getLastSuccessful(jobName) {
	assert jobName != null
	return Jenkins.getInstance().getItemByFullName(jobName).lastSuccessfulBuild.number 
}