Part of https://medium.com/@icheko/jenkinsfile-runner-f01930513572

Jenkinsfile

/*
This function is used to mount the Heroku .netrc
file into the heroku-cli container. The value of the
env variable should be of the form:
    /Users/jose.s.pacheco/.netrc:/root/.netrc

On production env.USER is defined as cloudbees so it
returns the production .netrc file

*/
def mount_heroku_auth() {
    node{
        if (env.USER == 'cloudbees') {
            echo 'mount_heroku_auth: returning HEROKU_AUTH_NETRC_PROD'
            return env.HEROKU_AUTH_NETRC_PROD
        } else {
            return env.HEROKU_AUTH_NETRC
        }
    }
}

pipeline{
    agent none
    stage('\u27A1 Git Checkout') {
        agent any
        when {
            environment ignoreCase: true, name: 'USER', value: 'cloudbees'
        }
        steps {
            checkout([
                $class: 'GitSCM',
                branches: [[name: 'master']],
                doGenerateSubmoduleConfigurations: false,
                extensions: [],
                submoduleCfg: [],
                userRemoteConfigs: [[
                    credentialsId: 'jose-s-pacheco-pat',
                    url: 'https://url/jose-s-pacheco/repo.git'
                ]]
            ])
            sh 'ls -al'
        }
    }
    stage('\u27A1 Build App'){
        agent {
            docker {
                image 'node:10-alpine'
                args '-u root -v $USER_HOME/node_modules:/workspace/jenkins/workspace/job/node_modules' // this second mount improves reruns on local
            }
        }
        steps {
            sh 'npm install -g @angular/cli@7.3.9'
            sh 'npm install'
            sh 'ng version'
            sh "ng build --configuration=$ENVIRONMENT"
        }
    }
    stage('\u27A1 Heroku Deployment'){
        agent {
            docker {
                image 'dickeyxxx/heroku-cli:latest'
                args '-u root -v ' + mount_heroku_auth() // heroku command needs root
            }
        }
        steps {
            sh 'rm -Rfv heroku-deployment'
            sh "heroku git:clone -a heroku-app heroku-deployment"
            dir('heroku-deployment'){
                sh 'heroku auth:whoami'
                sh "heroku info heroku-app"
                sh 'git config --global user.email "icheko@gmail.com"'
                sh 'git config --global user.name "Jose Pacheco"'
                sh 'cp -Rfv ../dist .'
                sh 'cp ../server.js .'
                sh 'cp ../package.json .'
                sh 'cp ../package-lock.json .'
                echo ''
                echo '--------------------------------------------'
                sh 'ls -al'
                sh 'git add .'
                sh 'git commit -m "Heroku Deployment" || echo "No changes to commit"'
                sh 'git push heroku master'
            }
        }
    }
}