Test your Node.js deployment

Prerequisites

Overview

In this section, you'll learn how to use Docker Desktop to deploy your application to a fully-featured Kubernetes environment on your development machine. This allows you to test and debug your workloads on Kubernetes locally before deploying.

Create a Kubernetes YAML file

In the cloned repository's directory, create a file named docker-node-kubernetes.yaml. Open the file in an IDE or text editor and add the following contents. Replace DOCKER_USERNAME/REPO_NAME with your Docker username and the name of the repository that you created in Configure CI/CD for your Node.js application.

apiVersion: apps/v1
kind: Deployment
metadata:
  name: docker-nodejs-demo
  namespace: default
spec:
  replicas: 1
  selector:
    matchLabels:
      todo: web
  template:
    metadata:
      labels:
        todo: web
    spec:
      containers:
      - name: todo-site
        image: DOCKER_USERNAME/REPO_NAME
        imagePullPolicy: Always
---
apiVersion: v1
kind: Service
metadata:
  name: todo-entrypoint
  namespace: default
spec:
  type: NodePort
  selector:
    todo: web
  ports:
  - port: 3000
    targetPort: 3000
    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 Node.js application.
  • A NodePort service, which will route traffic from port 30001 on your host to port 3000 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.

Deploy and check your application

  1. In a terminal, navigate to where you created docker-node-kubernetes.yaml and deploy your application to Kubernetes.

    $ kubectl apply -f docker-node-kubernetes.yaml

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

    deployment.apps/docker-nodejs-demo created
service/todo-entrypoint created

  2. Make sure everything worked by listing your deployments.

    $ kubectl get deployments

    Your deployment should be listed as follows:

    NAME                 READY   UP-TO-DATE   AVAILABLE   AGE
docker-nodejs-demo   1/1     1            1           6s

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

    $ kubectl get services

    You should get output like the following.

    NAME              TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)          AGE
kubernetes        ClusterIP   10.96.0.1        <none>        443/TCP          7d22h
todo-entrypoint   NodePort    10.111.101.229   <none>        3000:30001/TCP   33s

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

  3. Open a browser and visit your app at localhost:30001. You should see your application.

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

    $ kubectl delete -f docker-node-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: