template:
    metadata:
      labels:
        service: shiny
    spec:
      containers:
        - name: shiny-service
          image: DOCKER_USERNAME/REPO_NAME
          imagePullPolicy: Always
          env:
            - name: POSTGRES_PASSWORD
              value: mysecretpassword
---
apiVersion: v1
kind: Service
metadata:
  name: service-entrypoint
  namespace: default
spec:
  type: NodePort
  selector:
    service: shiny
  ports:
    - port: 3838
      targetPort: 3838
      nodePort: 30001
```

In this Kubernetes YAML file, there are two objects, separated by the `---`:

- A Deployment, describing a scalable group of identical pods. In this case,
  you'll get just one replica, or copy of your pod. That pod, which is
  described under `template`, has just one container in it. The
  container is created from the image built by GitHub Actions in [Configure CI/CD for
  your R application](configure-ci-cd.md).
- A NodePort service, which will route traffic from port 30001 on your host to
  port 3838 inside the pods it routes to, allowing you to reach your app
  from the network.

To learn more about Kubernetes objects, see the [Kubernetes documentation](https://kubernetes.io/docs/home/).

## Deploy and check your application

1. In a terminal, navigate to `r-docker-dev` and deploy your application to
   Kubernetes.

   ```console
   $ kubectl apply -f docker-r-kubernetes.yaml
   ```

   You should see output that looks like the following, indicating your Kubernetes objects were created successfully.

   ```text
   deployment.apps/docker-r-demo created
   service/service-entrypoint created
   ```

2. Make sure everything worked by listing your deployments.

   ```console
   $ kubectl get deployments
   ```

   Your deployment should be listed as follows:

   ```shell
   NAME                 READY   UP-TO-DATE   AVAILABLE   AGE
   docker-r-demo   1/1     1            1           15s
   ```

   This indicates all one of the pods you asked for in your YAML are up and running. Do the same check for your services.

   ```console
   $ kubectl get services
   ```

   You should get output like the following.

   ```shell
   NAME                 TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)          AGE
   kubernetes           ClusterIP   10.96.0.1       <none>        443/TCP          23h
   service-entrypoint   NodePort    10.99.128.230   <none>        3838:30001/TCP   75s
   ```

   In addition to the default `kubernetes` service, you can see your `service-entrypoint` service, accepting traffic on port 30001/TCP.

3. In a browser, visit the following address. Note that a database was not deployed in
   this example.

   ```console
   http://localhost:30001/
   ```

4. Run the following command to tear down your application.

   ```console
   $ kubectl delete -f docker-r-kubernetes.yaml
   ```

## Summary

In this section, you learned how to use Docker Desktop to deploy your application to a fully-featured Kubernetes environment on your development machine.

Related information:

- [Kubernetes documentation](https://kubernetes.io/docs/home/)
- [Deploy on Kubernetes with Docker Desktop](/manuals/desktop/features/kubernetes.md)
- [Swarm mode overview](/manuals/engine/swarm/_index.md)