kubectl-apply-on-dockerhub-push

This workflow sets a new image tag for a kubernetes deployment when an image is pushed to Docker Hub.

Prerequisites

Before you run this workflow, you will need the following:

• An account on Docker Hub
• An operating Kubernetes cluster with a deployment

Run the workflow

1. Add the workflow in Relay
2. Setup the Docker Hub webhook:
   • Click Setup
   • On the right sidebar, copy the webhook for the dockerhub-image-pushed trigger
   • Navigate to your repository on Docker Hub
   • Click Webhooks at the top
   • Add a name for your webhook and paste the url in the box Webhook URL
   • Click Create
3. Setup your Kubernetes connection
   • In the Relay page for the workflow, expand the Setup sidebar
   • In the sidebar, click the plus "+" under Connections for the Kubernetes connection and give it a name
   • Fill in the Cluster server field with the URL to your Kubernetes master (kubectl cluster-info will show this)
   • Paste the PEM-encoded CA certificate for your cluster in the Certificate authority field. This command will display the CA cert: kubectl config view --raw --flatten -o json | jq -r '.clusters[] | select(.name == "'$(kubectl config current-context)'") | .cluster."certificate-authority-data"' | base64 --decode
   • Paste an access token into the Token field. This can be retrieved with the following command: kubectl config view --raw --minify --flatten -o jsonpath='{.users[].user.auth-provider.config.access-token}'
4. Creating a new tag for your docker image and pushing it to Docker Hub should result in an update to your deployment container. You can validate with: kubectl -n <namespace> get deployments <deploymentName> -o=jsonpath='{.metadata.name}{": "}{range .spec.template.spec.containers[*]}{.image}{end}'.