Simple Node.js Web App

This is a simple Node.js web app using the Express framework. It serves the index.html file. The app can be containerize using Docker and deployed to any Kubernetes cluster. There is an example delpoyment config file to run it in AWS Elastic Kubernetes Service (EKS) from a Docker image in a AWS Elastic Container Repository (ECR).

This is the Capstone project for Udacity Devops Engineering Nanodegree.

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Running the App in Docker

1. Open a terminal and clone the project repository, then navigate to the project folder.

git clone https://github.com/softveda/udacity-devops-capstone.git
cd udacity-devops-capstone

2. Create Docker Image for the app

docker build -t simple_node_app .

3. Run the app in Docker container

 docker run --name simple_node_app -p 8080:80 -d simple_node_app

4. Test the app using Curl

curl -s http://localhost:8080

This should show the contents of index.html on the console.
Alternately open your web browser and browse to the URL http://localhost:8080

5. Check the logs

docker logs -f simple_node_app

This should write some logs to terminal like

Simple node web app listening on port 80
::ffff:192.168.65.3 - - [19/Apr/2020:01:24:46 +0000] "GET / HTTP/1.1" 200 337

6. Stop the running Docker container

 docker stop simple_node_app

Tagging and Uploading Docker image

1. Create a new repository on Docker hub named simple_web_app

2. Tag the image

docker tag simple_node_app:latest <docker account>/simple_node_app:latest

3. Push the image to Docker hub

docker push <docker account>/simple_node_app:latest

Deploy the Docker image to local Kubernetes Cluster

1. Deploy the application and service to Kubernetes

kubectl apply -f app-deployment.yml

2. Check that pods, deployment and service are created and running

kubectl get all

3. Test the app using Curl

curl -s http://localhost:8080

This should show the contents of index.html on the console.
Alternately open your web browser and browse to the URL http://localhost:8080

5. Check the logs

kubectl logs deployment.apps/simple-web-app

This should write some logs to terminal like

Simple node web app listening on port 80
::ffff:192.168.65.3 - - [19/Apr/2020:01:24:46 +0000] "GET / HTTP/1.1" 200 337

6. Delete the kubernetes deployment and service

kubectl delete deployment.apps/simple-web-app
kubectl delete service/simple-web-app

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Project Files

• Application files
  • app.js - This is the Node.js web application
  • views\index.html - This is the default index.html file
  • .eslintrc - ESLint configuration file
  • .gitignore - This has the files that should not be added to the git repository
• Docker files
  • Dockerfile - This is the docker build file to containerize the app inside Docker
  • .dockerignore - This has the files that should not be copied when building the Docker image
• Script files
  • run_docker.sh - This script will build the Docker image of the app and run the app inside the container
  • upload_docker.sh - This script uploads the Docker image to Docker hub repository
  • run_kubernetes.sh - This script deploys the Docker image to a Kubernetes cluster and runs the app in pods.