nodejs-helloworld -- Installation Guide

1. Setup Pre-requisites

Install Docker on your system

As this guide is for Mac, I will list the URL for Mac here: https://docs.docker.com/docker-for-mac/install/

Enable Kubernetes

After installing Docker for Mac, you have to enable Kubernetes in docker. Follow this guide to do this: https://docs.docker.com/docker-for-mac/#kubernetes

Ingress Controller

We need an Ingress controller to access the application on our system that is deployed on Kubernetes. Ingress controller can be installed from here: https://kubernetes.github.io/ingress-nginx/deploy/

Helm Client

Install the latest package of helm client from this path: https://helm.sh/docs/intro/install/ If you have brew installed, you can install helm with command: brew install helm

2. Jenkins Startup

There is a script named bootstrap.sh on the root of this repository. Execute this script to start Jenkins on your system.

bash <(curl -Ls https://raw.githubusercontent.com/umairadeeb/nodejs-helloworld/master/bootstrap.sh)

Once the Jenkins server is started, your can access it at:

Jenkins URL: http://localhost/jenkins

Username: admin

Password: admin

Install JRE to run Jenkins agent.

To run Jenkins agent on your system, you need JRE. Install JRE from here: https://www.oracle.com/java/technologies/javase-jre8-downloads.html

3. Start Jenkins Agent

After logging into Jenkins, go to below url and run the agent.jar on your system to connect your host to Jenkins server.

• Jenkins Agent URL: http://localhost/jenkins/computer/parent/
• Download agent.jar: http://localhost/jenkins/jnlpJars/agent.jar

Change current working directory to where the agent.jar downloaded (usually ~/Downloads/).

Now copy command written as java -jar agent.jar ... on Jenkins Agent page and execute it on your system's terminal where you changed current working directory.

4. Build NodeJS Application

On Jenkins server UI, there is a job named as Build that will create a Docker image for NodeJS application.

5. Deploy NodeJS Application

Once Build job is completed successfully, you can run Deploy job to deploy the application on dev or prod environment. When this job is executed first time, it will by default deploy on dev environment.

Application can be accessed after deployment at this URL: http://localhost

Notes about the techstack used

• Docker
• Kubernetes
• Ingress controller (for kubernetes)
• Helm
• Nodejs (to write hello world app)
• MariaDB (to store nodejs app data)
• Environment specific application properties using helm
• Jenkins
• Jenkins Shared Library
• Jenkins Configuration as Code plugin
• Jenkins Job DSL plugin
• Jenkins Startup trigger plugin
• Both DEV and PROD environments are deployed on different namespaces to keep them in a separate sandbox
• Subchart for MariaDB

Improvements

• Support for Blue/Green deployments
• More modular code for Jenkins Shared Library
• Implement github webhooks to fully automate Pull Request Builds, Deploy on merge, and environment promotion using pull requests to upstream branches or release tags.
• Semantic versioning based on github commit sha1 and build number.