The goal of this tutorial is for you to turn a simple Hello World Node.js app into an application running on Kubernetes. The tutorial shows you how to take code that you have developed on your machine, turn it into a Docker container image and then run that image on Minikube. Minikube provides a simple way of running Kubernetes on your local machine for free.
For OS X, you need Homebrew to install the
NodeJS is required to run the sample application.
Install Docker. On OS X, we recommend Docker for Mac.
This tutorial uses Minikube to create a local cluster. This tutorial also assumes you are using Docker for Mac on OS X. If you are on a different platform like Linux, or using VirtualBox instead of Docker for Mac, the instructions to install Minikube may be slightly different. For general Minikube installation instructions, see the Minikube installation guide.
curl to download and install the latest Minikube release:
curl -Lo minikube https://storage.googleapis.com/minikube/releases/latest/minikube-darwin-amd64 && \ chmod +x minikube && \ sudo mv minikube /usr/local/bin/
Use Homebrew to install the xhyve driver and set its permissions:
brew install docker-machine-driver-xhyve sudo chown root:wheel $(brew --prefix)/opt/docker-machine-driver-xhyve/bin/docker-machine-driver-xhyve sudo chmod u+s $(brew --prefix)/opt/docker-machine-driver-xhyve/bin/docker-machine-driver-xhyve
Use Homebrew to download the
kubectl command-line tool, which you can
use to interact with Kubernetes clusters:
brew install kubectl
Determine whether you can access sites like https://cloud.google.com/container-registry/ directly without a proxy, by opening a new terminal and using
curl --proxy "" https://cloud.google.com/container-registry/
If NO proxy is required, start the Minikube cluster:
minikube start --vm-driver=xhyve
If a proxy server is required, use the following method to start Minikube cluster with proxy setting:
minikube start --vm-driver=xhyve --docker-env HTTP_PROXY=http://your-http-proxy-host:your-http-proxy-port --docker-env HTTPS_PROXY=http(s)://your-https-proxy-host:your-https-proxy-port
--vm-driver=xhyve flag specifies that you are using Docker for Mac. The
default VM driver is VirtualBox.
Now set the Minikube context. The context is what determines which cluster
kubectl is interacting with. You can see all your available contexts in the
kubectl config use-context minikube
kubectl is configured to communicate with your cluster:
The next step is to write the application. Save this code in a folder named
with the filename
Run your application:
You should be able to see your “Hello World!” message at http://localhost:8080/.
Stop the running Node.js server by pressing Ctrl-C.
The next step is to package your application in a Docker container.
Create a file, also in the
hellonode folder, named
Dockerfile. A Dockerfile describes
the image that you want to build. You can build a Docker container image by extending an
existing image. The image in this tutorial extends an existing Node.js image.
This recipe for the Docker image starts from the official Node.js LTS image
found in the Docker registry, exposes port 8080, copies your
to the image and start the Node.js server.
Because this tutorial uses Minikube, instead of pushing your Docker image to a registry, you can simply build the image using the same Docker host as the Minikube VM, so that the images are automatically present. To do so, make sure you are using the Minikube Docker daemon:
eval $(minikube docker-env)
Note: Later, when you no longer wish to use the Minikube host, you can undo
this change by running
eval $(minikube docker-env -u).
Build your Docker image, using the Minikube Docker daemon:
docker build -t hello-node:v1 .
Now the Minikube VM can run the image you built.
A Kubernetes Pod is a group of one or more Containers, tied together for the purposes of administration and networking. The Pod in this tutorial has only one Container. A Kubernetes Deployment checks on the health of your Pod and restarts the Pod’s Container if it terminates. Deployments are the recommended way to manage the creation and scaling of Pods.
kubectl run command to create a Deployment that manages a Pod. The
Pod runs a Container based on your
hello-node:v1 Docker image:
kubectl run hello-node --image=hello-node:v1 --port=8080
View the Deployment:
kubectl get deployments
NAME DESIRED CURRENT UP-TO-DATE AVAILABLE AGE hello-node 1 1 1 1 3m
View the Pod:
kubectl get pods
NAME READY STATUS RESTARTS AGE hello-node-714049816-ztzrb 1/1 Running 0 6m
View cluster events:
kubectl get events
kubectl config view
For more information about
kubectlcommands, see the
By default, the Pod is only accessible by its internal IP address within the
Kubernetes cluster. To make the
hello-node Container accessible from outside the
Kubernetes virtual network, you have to expose the Pod as a
From your development machine, you can expose the Pod to the public internet
kubectl expose command:
kubectl expose deployment hello-node --type=LoadBalancer
View the Service you just created:
kubectl get services
NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE hello-node 10.0.0.71 <pending> 8080/TCP 6m kubernetes 10.0.0.1 <none> 443/TCP 14d
--type=LoadBalancer flag indicates that you want to expose your Service
outside of the cluster. On cloud providers that support load balancers,
an external IP address would be provisioned to access the Service. On Minikube,
LoadBalancer type makes the Service accessible through the
minikube service hello-node
This automatically opens up a browser window using a local IP address that serves your app and shows the “Hello World” message.
Assuming you’ve sent requests to your new web service using the browser or curl, you should now be able to see some logs:
kubectl logs <POD-NAME>
server.js file to return a new message:
response.end('Hello World Again!');
Build a new version of your image:
docker build -t hello-node:v2 .
Update the image of your Deployment:
kubectl set image deployment/hello-node hello-node=hello-node:v2
Run your app again to view the new message:
minikube service hello-node
Now you can clean up the resources you created in your cluster:
kubectl delete service hello-node kubectl delete deployment hello-node
Optionally, stop Minikube: