Jenkinsfile

// Example Jenkins pipeline with Cypress end-to-end tests running in parallel on 2 workers
// Pipeline syntax from https://jenkins.io/doc/book/pipeline/

// Setup:
//  before starting Jenkins, I have created several volumes to cache
//  Jenkins configuration, NPM modules and Cypress binary

// docker volume create jenkins-data
// docker volume create npm-cache
// docker volume create cypress-cache

// Start Jenkins command line by line:
//  - run as "root" user (insecure, contact your admin to configure user and groups!)
//  - run Docker in disconnected mode
//  - name running container "blue-ocean"
//  - map port 8080 with Jenkins UI
//  - map volumes for Jenkins data, NPM and Cypress caches
//  - pass Docker socket which allows Jenkins to start worker containers
//  - download and execute the latest BlueOcean Docker image

// docker run \
//   -u root \
//   -d \
//   --name blue-ocean \
//   -p 8080:8080 \
//   -v jenkins-data:/var/jenkins_home \
//   -v npm-cache:/root/.npm \
//   -v cypress-cache:/root/.cache \
//   -v /var/run/docker.sock:/var/run/docker.sock \
//   jenkinsci/blueocean:latest

// If you start for the very first time, inspect the logs from the running container
// to see Administrator password - you will need it to configure Jenkins via localhost:8080 UI
//    docker logs blue-ocean

pipeline {
  agent {
    // this image provides everything needed to run Cypress
    docker {
      image 'cypress/base:10'
    }
  }

  stages {
    // first stage installs node dependencies and Cypress binary
    stage('build') {
      steps {
        // there a few default environment variables on Jenkins
        // on local Jenkins machine (assuming port 8080) see
        // http://localhost:8080/pipeline-syntax/globals#env
        echo "Running build ${env.BUILD_ID} on ${env.JENKINS_URL}"
        sh 'npm ci'
        sh 'npm run cy:verify'
      }
    }

    stage('start local server') {
      steps {
        // start local server in the background
        // we will shut it down in "post" command block
        sh 'nohup npm run start &'
      }
    }

    // this stage runs end-to-end tests, and each agent uses the workspace
    // from the previous stage
    stage('cypress parallel tests') {
      environment {
        // we will be recording test results and video on Cypress dashboard
        // to record we need to set an environment variable
        // we can load the record key variable from credentials store
        // see https://jenkins.io/doc/book/using/using-credentials/
        CYPRESS_RECORD_KEY = credentials('cypress-example-kitchensink-record-key')
        // because parallel steps share the workspace they might race to delete
        // screenshots and videos folders. Tell Cypress not to delete these folders
        CYPRESS_trashAssetsBeforeRuns = 'false'
      }

      // https://jenkins.io/doc/book/pipeline/syntax/#parallel
      parallel {
        // start several test jobs in parallel, and they all
        // will use Cypress Dashboard to load balance any found spec files
        stage('tester A') {
          steps {
            echo "Running build ${env.BUILD_ID}"
            sh "npm run e2e:record:parallel"
          }
        }

        // second tester runs the same command
        stage('tester B') {
          steps {
            echo "Running build ${env.BUILD_ID}"
            sh "npm run e2e:record:parallel"
          }
        }
      }

    }
  }

  post {
    // shutdown the server running in the background
    always {
      echo 'Stopping local server'
      sh 'pkill -f http-server'
    }
  }
}