{
 "name": "docker_web_app",
 "version": "1.0.0",
 "description": "Node.js on Docker",
 "author": "First Last <first.last@example.com>",
 "main": "server.js",
 "scripts": {
 "start": "node server.js"
 },
 "dependencies": {
 "express": "^4.16.1"
 }
}

'use strict';

const express = require('express');

// Constants
const PORT = 8080;
const HOST = '0.0.0.0';

// App
const app = express();
app.get('/', (req, res) => {
 res.send('Hello World');
});

app.listen(PORT, HOST);
console.log(`Running on http://${HOST}:${PORT}`);

touch Dockerfile

FROM node:12

# Create app directory
WORKDIR /usr/src/app

# Install app dependencies
# A wildcard is used to ensure both package.json AND package-lock.json are copied
# where available (npm@5+)
COPY package*.json ./

RUN npm install
# If you are building your code for production
# RUN npm ci --only=production

# Bundle app source
COPY . .

EXPOSE 8080

CMD [ "node", "server.js" ]

FROM node:12

# Create app directory
WORKDIR /usr/src/app

# Install app dependencies
# A wildcard is used to ensure both package.json AND package-lock.json are copied
# where available (npm@5+)
COPY package*.json ./

RUN npm install
# If you are building your code for production
# RUN npm ci --only=production

# Bundle app source
COPY . .

EXPOSE 8080
CMD [ "node", "server.js" ]

node_modules
npm-debug.log

docker build -t <your username>/node-web-app .

$ docker images

# Example
REPOSITORY      TAG  ID    CREATED
node       12   1934b0b038d1 5 days ago
<your username>/node-web-app latest  d64d3505b0d2 1 minute ago

docker run -p 49160:8080 -d <your username>/node-web-app

# Enter the container
$ docker exec -it <container id> /bin/bash

$ docker ps

# Example
ID   IMAGE        COMMAND ... PORTS
ecce33b30ebf <your username>/node-web-app:latest npm start ... 49160->8080

$ curl -i localhost:49160

HTTP/1.1 200 OK
X-Powered-By: Express
Content-Type: text/html; charset=utf-8
Content-Length: 12
ETag: W/"c-M6tWOb/Y57lesdjQuHeB1P/qTV0"
Date: Mon, 13 Nov 2017 20:53:59 GMT
Connection: keep-alive

Hello world