Dockerizing a Node.js web application

In this article, I would like to document how I dockerize my portfolio web site, which is a Node.js application.

Table of Contents

• Build the Node.js application
• Deployment
• Verification

Build the Node.js application

Firstly, create Dockerfile for the Node.js application.

FROM node:14.18.2-alpine3.14
WORKDIR /app
COPY package.json ./
COPY package-lock.json ./
COPY ./ ./
RUN npm ci
CMD ["npm", "run", "start"]

Since I've used node-sass package for enabling SASS in my application and the package supports limited Node.js version, I need to find the right node.js docker image at docker hub.

At docker hub, search for the right image in the Tags tab. Once the desired image is found, put it on the first line (i.e. the FROM layer) of the Dockerfile.

Secondly, create .dockerignore file to exclude files and directories from the docker image.

node_modules
*.log

Thirdly, build the Node.js application.

yarn build

Fourthly, build the docker image.

*Make sure Docker Engine is running in your development environment.

docker build -f Dockerfile -t portfolio-website .

Deployment

• Deploy by exposing port 5001 instead of default port 3000 (you can change to any port according to your environment).

docker run --name portfolio-website -it -p 5001:3000 portfolio-website

Verification

• Check that the web application is running by opening http://localhost:5001/ in a web browser.

Comments

[Alexander Staroselsky]

Could consider only installing production packages to greatly reduce the size of the image and speed up the build. npm ci —production

[Ada Cheng]

Thanks a lot for your advice!