Deploying a Node.js app to the Google Kubernetes Engine (GKE)

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Let us show you how quickly and easily you can deploy your app to Kubernetes on Google Kubernetes Engine (GKE).

Create a new Kubernetes cluster

Enter a name for your cluster, the location, the number of nodes and the machine type. Then click More Options.

If you need to automatically add new nodes to the cluster, then click Enable autoscaling.

You can allow access to some APIs from the cluster. For example, I allow access to Google Cloud Storage (GCS).

After your cluster has been created, click Connect.

Now you’ll see a Cloud Shell containing the command; press Enter to execute it and get GKE credentials. After that, you can execute any commands with kubectl.

For example, let’s check the nodes of a cluster.

Push docker image to Google Container Registry

I’ll use my GitHub repo, which includes a simple Node.js app, Dockerfile, and deployment.yaml. I’ll enter all the following commands in Cloud Shell.

git clone https://github.com/sonufrienko/gke-simple-app

cd gke-simple-app

Replace [PROJECT_ID] in deployment.yaml with your GCP project ID.

Get credentials to Google Container Registry

gcloud auth configure-docker

Build and push the docker image to Google Container Registry

docker build -t gcr.io/[PROJECT_ID]/app:v1 .

docker push gcr.io/[PROJECT_ID]/app:v1

Deploy docker image to Kubernetes

A deployment YAML file contains two parts:

• Deployment – describes the containers to be deployed
• Service – will create a LoadBalancer to expose our containers to the internet

Create deployment and service

kubectl apply -f deployment.yaml --record

Check the deployment process

kubectl get deployments

Check the pods (containers)

kubectl get pods

Check the service and copy the external IP address (LoadBalancer)

kubectl get services

Now, you can open this URL in your browser:

http://<EXTERNAL-IP>/encrypt?secret=abc&message=i-love-you

How to release a new version?

Push a new version of a docker image to the Container Registry, change the docker image version in deployment.yaml and then run this command to set desired deployment state:

kubectl apply -f deployment.yaml --record

How to rollback a new release?

kubectl rollout undo deployment/my-app-deployment

Useful tips

Check container logs

kubectl logs <POD NAME>

Go inside a container

kubectl exec -it <POD NAME> bash

Delete a whole deployment

kubectl delete deployment my-app-deployment

Set horizontal pod autoscaling policy for deployment

kubectl autoscale deployment <DEPLOYMENT_NAME> --max 6 --min 1 --cpu-percent 60

Check horizontal pod autoscaling policy (HorizontalPodAutoscaler object)

kubectl get hpa

Check pod Events to investigate issues with pod deployment, polling docker image, etc.