Set Up a Jenkins Build Server

Ubuntu

• Conect to Ubuntu

ssh -i /path/my-key-pair.pem user_name@public_dns_name

• Install Node JS

curl -sL https://deb.nodesource.com/setup_8.x | sudo -E bash -
sudo apt-get install -y nodejs

• Install Git

sudo apt-get install git

• Install Jenckins

wget -q -O - https://pkg.jenkins.io/debian-stable/jenkins.io.key | sudo apt-key add -

sudo nano /etc/apt/sources.list

add next line deb https://pkg.jenkins.io/debian-stable binary/

sudo apt-get update

sudo apt-get install jenkins

If you have error Failed to start LSB: Start Jenki install Java Runtime Environment:

sudo apt install openjdk-8-jre

or so to fix that you should chose version 8 as your default java environment by simply running sudo update-alternatives --config java and then chosing your version 8

• Start Jenkins

sudo service jenkins start

If need restsart Jenkins server: sudo service jenkins restart

• Connect to http://<your_server_public_DNS>:8080

• As prompted, enter the password found in /var/lib/jenkins/secrets/initialAdminPassword. Use the following command to display this password:

sudo cat /var/lib/jenkins/secrets/initialAdminPassword

• Install plagins:

  • Folders
  • Build Timeout
  • Timestamper
  • Pipeline
  • Pipeline: Stage View
  • Git
  • Git Parameter
  • GitHub

---

• Login to Server using SSH
  • Conect to Ubuntu

  ssh -i /path/my-key-pair.pem user_name@public_dns_name
  

  • Jenkins automatically creates a new user after installation. Switch to it using this command.

  sudo su
  su jenkins
  

  • Let’s generate RSA key, run following command.

  ssh-keygen -t rsa
  

  • Press Enter for the location and do not type any password when it asks to, just hit enter.

  • Once the process is completed, print the public key information using this command.

  cat ~/.ssh/id_rsa.pub
  

  • It should start with ssh-rsa and ends with jenkins@droplet-ip. Copy the key.

  • Now login to your development server and switch to ~/.ssh directory using following command.

  exit
  exit
  cd ~/.ssh
  

  • Now open the file named authorized_keys if its present, else create one.

  nano authorized_keys
  

  • Paste the key in the file, if there is already some information is present, just append the key in the new line and do not change anything else.

  • Once done save the file.

  • In order to validate whether keys are properly configured or not, switch to Jenkins Server and try to login to development server using SSH.

  sudo su
  su jenkins
  ssh user_name@public_dns_name
  

  • If it’s not asking any password and log in successfully, you are good to go.

---

Add environment variables

• Jenkinsfile

node {
  timestamps {
    stage('Check out') {
      checkout scm
    }

    stage('Get dependencies') {
      sh 'npm install'
    }

    stage('Tslint') {
      sh 'npm run tslint'
    }

    stage('Run Test') {
      echo 'Run Test...'
    }

    stage('Deploy') {
      echo 'Stopping old process to run new process...'
      if (env.BUILD_NUMBER == '1') {
        echo 'Clone repository...'
        sh '''
          ssh ${ADMIN_USER}@${DNS} <<EOF
            git clone https://github.com/SIARHEI-SMANTSAR/set-up-a-jenkins-build-server.git
            exit
          EOF
        '''
      }
      sh '''
        ssh ${ADMIN_USER}@${DNS} <<EOF
          cd set-up-a-jenkins-build-server
          git pull
          npm install
          npm run pm2-stop
          npm run pm2-start
          exit
        EOF
      '''
    }
  }
}

• Connect to http://<your_server_public_DNS>:4000

---

Links

• Continuous Integration and deployment with Jenkins and Node.js
• Set Up a Jenkins Build Server