Prerequisite: First You have to install some Prerequisites for this deployment. Click here to set up the prerequisite.

Step 1: Clone the source code

The first step is to clone the source code for the app. You can do this by using this command git clone https://github.com/LondheShubham153/reddit-clone-k8s-ingress.git

Step 2: Containerize the Application using Docker

Write a Dockerfile with the following code:


FROM node:19-alpine3.15

WORKDIR /reddit-clone

COPY . /reddit-clone

RUN npm install 

EXPOSE 3000

CMD ["npm","run","dev"]

Step 3) Building Docker-Image

Now it's time to build Docker Image from this Dockerfile. docker build -t <DockerHub_Username>/<Imagename> . use this command to build a docker image.

Step 4) Push the Image To DockerHub

Now push this Docker Image to DockerHub so our Deployment file can pull this image & run the app in Kubernetes pods.

First login to your DockerHub account using Command i.e docker login and give your username & password.
Then use docker push <DockerHub_Username>/<Imagename> for pushing to the DockerHub.
You can use an existing docker image i.e trainwithshubham/reddit-clone for deployment.

Step 5) Write a Kubernetes Manifest File

Now, You might be wondering what this manifest file in Kubernetes is. Don't worry, I'll tell you in brief.

When you are going to deploy to Kubernetes or create Kubernetes resources like a pod, replica-set, config map, secret, deployment, etc, you need to write a file called manifest that describes that object and its attributes either in yaml or json. Just like you do in the ansible playbook.

Of course, you can create those objects by using just the command line, but the recommended way is to write a file so that you can version control it and use it in a repeatable way.

Write Deployment.yml file

Let's Create a Deployment File For our Application. Use the following code for the Deployment.yml file.

apiVersion: apps/v1
kind: Deployment
metadata:
  name: reddit-clone-deployment
  labels:
    app: reddit-clone
spec:
  replicas: 2
  selector:
    matchLabels:
      app: reddit-clone
  template:
    metadata:
      labels:
        app: reddit-clone
    spec:
      containers:
      - name: reddit-clone
        image: trainwithshubham/reddit-clone
        ports:
        - containerPort: 3000

Write Service.yml file

apiVersion: v1
kind: Service
metadata:
  name: reddit-clone-service
  labels:
    app: reddit-clone
spec:
  type: NodePort
  ports:
  - port: 3000
    targetPort: 3000
    nodePort: 31000
  selector:
    app: reddit-clone

Step 5) Deploy the app to Kubernetes & Create a Service For It

Now, we have a deployment file for our app and we have a running Kubernetes cluster, we can deploy the app to Kubernetes. To deploy the app you need to run following the command: kubectl apply -f Deployment.yml Just Like this create a Service using kubectl apply -f Service.yml

If You want to check your deployment & Service use the command kubectl get deployment & kubectl get services

Step 6) Let's Configure Ingress

Ingress:

Pods and services in Kubernetes have their own IP; however, it is normally not the interface you'd provide to the external internet. Though there is a service with node IP configured, the port in the node IP can't be duplicated among the services. It is cumbersome to decide which port to manage with which service. Furthermore, the node comes and goes, it wouldn't be clever to provide a static node IP to an external service. Ingress defines a set of rules that allows the inbound connection to access Kubernetes cluster services. It brings the traffic into the cluster at L7 and allocates and forwards a port on each VM to the service port. This is shown in the following figure. We define a set of rules and post them as source type ingress to the API server. When the traffic comes in, the ingress controller will then fulfill and route the ingress by the ingress rules. As shown in the following figure, ingress is used to route external traffic to the Kubernetes endpoints by different URLs:

Let's write ingress.yml and put the following code in it:

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: ingress-reddit-app
spec:
  rules:
  - host: "domain.com"
    http:
      paths:
      - pathType: Prefix
        path: "/test"
        backend:
          service:
            name: reddit-clone-service
            port:
              number: 3000
  - host: "*.domain.com"
    http:
      paths:
      - pathType: Prefix
        path: "/test"
        backend:
          service:
            name: reddit-clone-service
            port:
              number: 3000

Minikube doesn't enable ingress by default; we have to enable it first using minikube addons enable ingress command.

If you want to check the current setting for addons in minikube use minikube addons list command.

Now you can able to create ingress for your service. kubectl apply -f ingress.yml use this command to apply ingress settings.

Verify that the ingress resource is running correctly by using kubectl get ingress ingress-reddit-app command.

Step 8) Expose the app

First We need to expose our deployment so use kubectl expose deployment reddit-clone-deployment --type=NodePort command.
You can test your deployment using curl -L http://192.168.49.2:31000. 192.168.49.2 is a minikube ip & Port 31000 is defined in Service.yml
Then We have to expose our app service kubectl port-forward svc/reddit-clone-service 3000:3000 --address 0.0.0.0 &

Test Ingress

Now It's time to test your ingress so use the curl -L domain/test command in the terminal.

You can also see the deployed application on Ec2_ip:3000

Note:- Make sure you open the 3000 port in a security group of your Ec2 Instance.

You have successfully Deployed a Reddit Copy on Kubernetes with Ingress Enabled.

Thanks all. Good luck out there!

Follow for more such amazing content :)

Happy Learning 😊

TrainWithShubham Community Blog