In this article, we’re going to create a simple Node.js hello world docker container. Let’s get started:

You can take a look at basic docker commands.

Table of Contents

1. Create Simple Project
2. Create Dockerfile
3. Create Docker Image

Create Simple Project

Let’s create a super simple Node.js project. Create a project folder named node-docker-hello-world and go to the folder via CMD. Then run this two commands:

# init project
npm init -y

# install express.js
npm install express

Now create a file called index.js and paste this code:

// load express module with `require` directive
var express = require('express')
var app = express()

// define request response in root URL (/)
app.get('/', function (req, res) {
  res.send('Hello World!')
})

// launch listening server on port 3000
app.listen(3000, function () {
  console.log('app listening on port 3000!')
})

Run the project and test it works or not:

node index.js

Our project is working. Let’s drive to next step.

Create Dockerfile

We need to define Dockerfile to create docker container:

FROM node:alpine
WORKDIR /home/node/app
COPY package*.json index.js ./
RUN npm install
EXPOSE 3000
CMD [ "node", "index.js" ]

Create .dockerignore and add these lines:

node_modules
.git
.cache

The .dockerignore file works file .gitignore.

Create Docker Image

From the root folder, run this command to build docker image:

docker build -t nodehello ./

It may take a few minutes to build image. After creating the image, we’re able to see the image using docker images command.

Now we can run a container from the image:

docker run -d -p 3000:3000 nodehello

 The app will run on port 3000. We can run the app on port 80 by this command:

docker run -d -p 80:3000 nodehello

Now visit http://localhost and see the output. We can see the list of running containers by this command:

docker ps

The tutorial is over. You can download this project from GitHub. Thank you. ?

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