Using Docker for local Node.js development

Erzhan Torokulov

Dec 16, 2018·2 min read

This article shows how to create a simple Node.js app and setup Docker for running the app locally in watch mode inside a container.

Why use Docker for development?

• Easy starting. New developers need only Docker CE as a prerequisite.
• The same environment. Everyone working on the project will have the exact same environment (including Nodejs and npm versions, as well as node_modules, if using package-lock.json or yarn.lock). Also min diff with production environment, if app runs in docker container on prod.

Prerequisites:

• Docker CE(community edition). You can find and install from the Docker official website.

Creating Node.js app

1. Create a new project.

# Create new app directory 
npm i my-app # Initialize with 
npm init -y # Install express 
npm i express --save  # Install nodemon for running an app in watch mode
npm i nodemon --save-dev #create src dir and file inside 
mkdir src && touch src/index.js

2. Edit src/index.js .

3. Add script to package.json.

"srcipts": {
  "dev": "nodemon src/index.js"
  ...
}

Configuring Dockerfile and docker-compose.yml

1. Add Dockerfile.

2. Add docker-compose.yml .

3. Add script to package.json .

"scripts": {
  "docker:dev": "docker-compose up"
  ...
}

Running all together

1. Run application in a docker container in watch mode: npm run docker:dev.

This will build a container using Dockerfile and mount local directory into the container’s app directory as well as start an app in watch mode.

2. You can check “http://localhost:3000”.

You can change your source files, nodemon will restart as usual on file changes.

Conclusion

All source code available on Github.