JenkinsfileCheatSheet.groovy

// Checking out the repository from github into your workspace:
checkout SCM

// Execute shell commands
sh "echo Hello World!"

// Branch-specific Behaviour: 
if (env.BRANCH_NAME == 'master') {
    stage ("promote staging"){
        // do stuff
    }
}

// Sending a message to a Slack Channel: 
slackSend channel: #Your-Slack-Channel, color: '#2ECC71', message: "Build succeeded!"