jenkins-scripts/publish/Jenkinsfile

stage ('publish') {
    echo 'checking tag'
    script {
        def tag = sh(returnStdout: true, script: "git tag --contains").trim()
        if (tag) {
            echo 'found tag ' + tag
            sh 'npm publish --access public'
        } else {
            echo 'tag not found'
        }
    }
}