Containers & Images

In this exercise, we will build a docker image for nodejs app. Will use dockerhub as registry and will run that image on our kubernetes cluster. Check the docker-demo directory. Verify three files shown below.
- Dockerfile
# cat Dockerfile
FROM node:4.6
WORKDIR /app
ADD . /app
RUN npm install
EXPOSE 3000
CMD npm start
- index.js
# cat index.js
var express = require('express');
var app = express();
app.get('/', function (req, res) {
res.send('Hello World!');
});
var server = app.listen(3000, function () {
var host = server.address().address;
var port = server.address().port;
console.log('Example app listening at http://%s:%s', host, port); });
- package.json
# cat package.json
{
"name": "myapp",
"version": "0.0.1",
"private": true,
"scripts": {
"start": "node index.js"
},
"engines": {
"node": "^4.6.1"
},
"dependencies": {
"express": "^4.14.0",
"mysql": "^2.10.2"
}
}
Install docker:

Build Image:
Images name should match with your docker hub account/reponame. For example, my account name in docker hub is “visualpath”, so my image name is visualpath/k8s-demo.