Deploy Your Vaadin App To Google Cloud Kubernetes

In this setup we’ll have a Kubernetes Cluster with a Load-balancer, running your app from a docker image, connected to a Google Cloud SQL running MySQL.

We will use the Vaadin-Kotlin-PWA example app in this tutorial.

Google Cloud is huge and contains lots of functionality; the documentation is vast, chatty, over-inflated and filled with buzzwords to the point it’s almost useless. This manual has been created with lots of tears and swearing :-D

Preparation Steps

You will need to create a Google Cloud Project from your Google Cloud console. Simply provide vok-pwa as the project name.

Create SQL Database VM

Go to the SQL menu tab and create the Google Cloud SQL Instance, choosing MySQL 5.7. During the installation, provide this password to root: PfJ739VoMMDrs.

Expand the “Configuration Options / Connectivity”, uncheck the “Public IP” and check the “Private IP”. If “Private IP” can not be checked because of Google APIs not being enabled, simply visit the Kubernetes Engine page first - the APIs will be enabled automatically.

Select the Default network for Private IP. Also click Allocate and connect button.

Once the SQL server is created, visit the VM details page and write down the Private IP Address, e.g.

Don’t forget to create the vok_pwa database after the SQL server is up.

Note: disabling the “Public IP” will leave the database inaccessible from your development machine. It’s not a problem for the server since it will use Flyway to bring the database schema up-to-date automatically, but you will be unable to see the database contents from your dev machine.

Preparing Local Env

You’ll need to install the docker-credential-gcr tool so that JIB can upload stuff into GCR:

  1. install the docker-credential-gcr
  2. authenticate via docker-credential-gcr gcr-login
  3. Install gcr into your docker by running docker-credential-gcr configure-docker
  4. Make sure that Google Container Registry (GCR) API is enabled on your project.
  5. Define the GC_PROJECT environment variable so that it’s easier to run the JIB build commands. Just set it to your Google Cloud Project ID, e.g. vok-pwa-256209.

Creating Kubernetes Cluster

Head to Kubernetes Engine / Clusters and select “Create Cluster”. I’ve selected the “Your First Cluster” option which creates a simple cluster of 1 node with 1,7GB of RAM, perfect for experimenting. Use “Location Type” “Zonal”, Node pool pool-1 of 1 node and Machine type g1-small.

Once that’s done, we need to create a Load Balancer, and for that we need to have an app deployed. To deploy VOK-PWA to Google Container Registry (GCR) you first need to create a Docker image and publish it to GCR:

./gradlew clean build jib$GC_PROJECT/vok_pwa

Once that’s done, select your Cluster and click the “Deploy” button. Select “Existing container image” and select the vok_pwa/latest image. Add the following environment variables:

  • VOK_PWA_JDBC_DRIVER = com.mysql.jdbc.Driver
  • VOK_PWA_JDBC_URL = jdbc:mysql://MYSQLIP:3306/vok_pwa?useUnicode=true

With these env variables we configure the VOK-PWA app to properly connect to our Google Cloud SQL database.

Replace MYSQLIP with the SQL Private IP Address as above, e.g. The rest of the Configuration doesn’t matter - select default Namespace, for example “VOK-PWA” as App Name; Labels are not used. Click the “Deploy” button.

Note: You can now verify that the node booted up properly, by visiting Workloads / VOK-PWA and clicking the “Container Logs” link.

In the Workloads tab, click “VOK-PWA”. If there is the “Does Not Have Minimum Availability” error, see below for troubleshooting tips. There will be a warning regarding the visibility “To let others access your deployment, expose it to create a service” - follow the warning and create a Load Balancer. Make sure to setup port forwarding from 80 to 8080. The Load Balancer will be created with a Static IP.

You can figure out the Load Balancer Static IP by visiting Kubernetes Engine / Service & Ingress and checking out the link in the “Endpoints” column in the list.

Now you can simply browse http://LOAD_BALANCER_IP:80 and the VOK-PWA app will be running.

Updating VOK-PWA in Kubernetes Cluster

To update a newer version of VOK-PWA to your Google Container Registry you first need to create a Docker image and publish it to GCR:

./gradlew clean build jib$GC_PROJECT/vok_pwa:2

Once that’s done, go into Workloads / VOK-PWA / Actions / Rolling update, set as Image, then click “Update”.

Viewing App Logs

Go to Kubernetes Engine / Workloads tab, click “VOK-PWA”, then click the “Container Logs” link.

If there is something wrong with the server and it won’t start up properly (e.g. because of invalid migration, database security issue etc), you will need to restart it. I have yet to figure out how to restart all pods :(


Q: The Workloads says “Does Not Have Minimum Availability” and “Pod errors: Unschedulable” and “Cannot schedule pods: Insufficient cpu.”.

A: Click Workloads / VOK-PWA / Actions / Autoscale and set min=1 max=1. Then click Workloads / VOK-PWA / Actions / Scale and type in “1”.

Q: Restart the pods since I forgot to create a database

A: I’ve found no way to restart pods other than publishing a new image and Roll-update to it.

Written on October 21, 2019