Jenkins Workflow

• Install Jenkins
  • DigitalOcean
  • Download Docker and install Jenkins
• Build and deploy application
  • Package the app in docker

Install Jenkins

Install Jenkins on the Cloud using Docker (DigitalOcean).

DigitalOcean

Setup DigitalOcean droplet and ssh into the machine:

ssh root@<ip-address>

Download Docker and install Jenkins

Run the scripts/install_jenkins.sh script inside the machine:

bash install_jenkins.sh

Docker will pull the official jenkins image and run the container:

Jenkins installed
You should now be able to access jenkins at: http://<ip-address>:8080

The initial admin password can be found in /var/jenkins_home/secrets/initialAdminPassword

The jenkins pipelines are located in the following directory in the host machine:

/var/jenkins_home/workspace/

Install Docker on the host machine

Run the following docker image as a container in the DigitalOcean machine, to get access to the Docker client, and to expose the Docker socket, so we can access the Docker API on the machine.

# clone the repo 
git clone https://github.com/HakimiX/jenkins-image
 
# build the image
 docker build -t jenkins-docker .

# Remove the old jenkins:latest image and use the new image
docker rm jenkins

# build and start the new image
docker run -p 8080:8080 -p 50000:50000 -v /var/jenkins_home:/var/jenkins_home -v /var/run/docker.sock:/var/run/docker.sock --name jenkins -d jenkins-docker

Jenkins will use the existing volume and restart.

Pull images
Pull an image from docker hub in the host machine:

docker pull hakimixx/docker-nodejs-demo

Start the container:

docker run -p 3000:3000 -d hakimixx/docker-nodejs-demo

Navigate to the host IP

http://<ip-address>:3000

Or use curl in the machine

curl http://localhost:3000

Build and deploy application

Building the app on Jenkins will:

• Install dependencies
• Build and push the application to docker hub:

Package the app in Docker

Create a container that includes the Node.js binaries and the app. This ensures that the code will behave in the same way on the production system as in the non-production environments.

Jenkins Job DSL vs. Jenkins Pipeline

• They both have the capability to write all CI/CD in code.
• The difference is in implementation in Jenkins.
• Jenkins Job DSL create new jobs based on the code.
• The jenkins pipelines are a job type, which are used to handle the build/test/deployment of a project.

Slack Integration

Slack App

• Incoming WebHooks

Docker compose

Installation in container

Run the following command to download the current stable release of Docker Compose:

DOCKER_CONFIG=${DOCKER_CONFIG:-$HOME/.docker}
mkdir -p $DOCKER_CONFIG/cli-plugins
curl -SL https://github.com/docker/compose/releases/download/v2.2.3/docker-compose-linux-x86_64 -o $DOCKER_CONFIG/cli-plugins/docker-compose

This command installs Compose V2 for the active user under $HOME directory. To install Docker Compose for all users on your system, replace ~/.docker/cli-plugins with /usr/local/lib/docker/cli-plugins. Apply executable permissions to the binary:

chmod +x $DOCKER_CONFIG/cli-plugins/docker-compose

Test the installation

docker compose version

Start Jenkins and Sonarqube

Start Jenkins server, Sonarqube and a Postgres database (for storing sonarqube data) in the host machine.

docker-compose up -f docker-compose/docker-compose.yml

# Jenkins
http://<ip-address>:8080

# Sonarqube 
http://<ip-address>:9000

Jenkins Plugins

• Nodejs
• CloudBees Docker Build and Publish
• Jenkins Job DSL (needed for groovy scripts)
• Docker Pipeline (needed for jenkins pipelines)
• GitHub Plugin (needed for push notification)
• Global Slack Notifier (Slack integration)

Jenkins Job DSL

API documentation