Pac-Man + NodeJS + MongoDB Microservices Application

This is an example Kubernetes application that hosts an HTML5 Pac-Man game with Node.js as the web server and backend to read and write data to a MongoDB database.

Pac-Man Game Architecture Overview

Pac-Man

The Pac-Man game is a modified version of the open source Pac-Man game written in HTML5 with Javascript. You can get the modified Pac-Man game source code here.

Node.js

Node.js is used as the server side component to host the Pac-Man game application. It uses a few packages such as the Express web application framework as well as the MongoDB driver for the backend Node.js API.

MongoDB

MongoDB is used as the backend database to store the Pac-Man game's high score user data.

Prerequisites

Clone This Repository

Clone this repo which contains the Kubernetes configs and Dockerfile resources.

git clone https://github.com/font/k8s-example-apps.git
cd k8s-example-apps/pacman-nodejs-app

Create Application Container Image

The Dockerfile performs the following steps:

1. It is based on Node.js LTS Version 6 (Boron).
2. It then clones the Pac-Man game into the configured application directory.
3. Exposes port 8080 for the web server.
4. Starts the Node.js application using npm start.

To build the image run:

cd docker
docker build -t <user>/pacman-nodejs-app .
cd ..

You can test the image by running:

docker run -p 8000:8080 <user>/pacman-nodejs-app

And going to http://localhost:8000/ to see if you get the Pac-Man game.

Container Registry

Create a Quay Account

Create a Quay account which allows unlimited storage and serving of public repositories.

Sign Into Your Quay Account

Run the following docker command to sign in:

$ docker login quay.io
Username: myusername
Password: mypassword

Push Container Image to Quay

You'll want to tag your previously created Docker image to use the URL and then push it:

docker tag <user>/pacman-nodejs-app quay.io/YOUR_USERNAME/pacman-nodejs-app
docker push quay.io/YOUR_USERNAME/pacman-nodejs-app

Once you've pushed your image, you'll need to update the Kubernetes resources to point to your image before you continue with the rest of the guides.

sed -i 's/ifont/YOUR_USERNAME/' deployments/pacman-deployment*.yaml

Make Container Image Public

Go the settings tab for your repository and modify the Repository Visibilty to make the repository public. To navigate directly there, replace <username> with your username: https://quay.io/repository//pacman-nodejs-app?tab=settings

Afer pushing, make sure to make your repository public on quay.io.

Kubernetes Cluster Use-Cases

You'll need to create 1 to at least 3 Kubernetes cluster(s) depending on whether you want to try out the Pac-Man app on 1 cluster, or try it out on multiple clusters. Below are links that will guide you through it.

Single Kubernetes Cluster

• Pac-Man Node.js App Single Cluster

Federated-v2 Kubernetes Cluster Use-Cases

Follow the instructions in the below links to test out different federation use-cases.

• Pac-Man application deployed on GKE k8s federated cluster
• Pac-Man application deployed on multiple public cloud providers in a federation: GKE, AWS, and Azure
• Pac-Man application portability: deploy on AWS, GKE, and Azure, then move away from AWS
• Pac-Man application portability: deploy on GKE and Azure, then swap Azure with AWS

Kubernetes Cluster Use-Cases (Without Federation)

• Pac-Man application migration using GKE
• Pac-Man application migration from AWS to GKE