web-app-template-k3d

Simple web app template written with Golang + Bootstrap 4 to be used to showcase the power of k3d containerized application to a Kubernetes cluster.

Usage

Install Golang
Clone this repo and go to that folder

go run main.go

Default server run on port 8080(this is before deploying k3d cluster), browse to

localhost:8080/home

Get result

License

This repo is available as open source under the terms of the MIT License.
You are welcome to contribute!

k3d-with-go

go-webapp-with-k3d

Deploy the webapps to a local k3d cluster

Containerizing the Application

First, let’s create a file named Dockerfile at the project root and add the following commands there.

Dockerfile

Using the “golang alpine” image for its compact size

ow let’s build the container using the build command while tagging it with the name “go-webapp.”

docker build -t go-webapp .

#Results

We can simply look at the images within docker using the image command and thereby verify the image creation.

docker images

#RESULT

Creating a Private Container Registry

The registry can be created using the registry create command. We will create a local private registry called “test-app-registry” using port 5050.

k3d registry create test-app-registry --port 5050

K3d provides users with the necessary steps to create a K8s cluster and push the images.

Before creating the cluster, let’s create a file named registries.yaml that will define the registry config for the cluster. It will help to route the traffic to this private registry properly.

registries.yaml

mirrors: "localhost:5050": endpoint: - http://k3d-test-app-registry:5050

Then, we can use the following command to construct the cluster. It will make use of the previously constructed container registry and a cluster load balancer on port 9900.

k3d cluster create mycluster -p "9900:80@loadbalancer" --registry-use k3d-test-app-registry:5050 --registry-config registries.yaml

Results

Pushing the Docker image to the Private Container Registry

We are almost there,tag the image with the registry name and push the image to the “k3d-test-app-registry” . Tag and Push the Local Docker image using the following commands.

docker tag go-web-server:latest localhost:5050/go-web-server:v1.0 docker push localhost:5050/go-web-server:v1.0

Create a Deployment

Then we can construct a service to expose the deployment and deploy using our image. Then, in order to grant access to it, we must create an ingress object.

Create the Deployment and Service

kubectl create deployment go-webapp --image=k3d-test-app-registry:5050/go-webapp:v1.0

#Results

kubectl create service clusterip go-web-server --tcp=9091:9091

RESULT

Create Ingress Object

Create the following file and apply it using the kubectl apply command.

ingress.yaml

apiVersion: networking.k8s.io/v1 kind: Ingress metadata: name: go-web-server annotations: ingress.kubernetes.io/ssl-redirect: "false" spec: rules:

• http: paths:
  • path: / pathType: Prefix backend: service: name: go-web-server port: number: 9091

kubectl apply -f .\ingress.yaml

RESULT

Successfully deployed your containerized application to a Kubernetes cluster. The deployed web server will be visible if you visit the cluster URL http://localhost:9900/.