💨 The fastest way to deploy your Javascript app to Kubernetes 🌬️ ✨

TL;DR

On this tutorial, you will discover ways to deploy your first javascript utility on Kubernetes – a container orchestration platform ☸️.

We are going to deploy a easy categorical server that returns a pattern JSON object on Kubernetes regionally utilizing Minikube ✨.

Stipulations 📜:

• Docker: For containerizing the applying. 🐋

• Minikube: For operating Kubernetes regionally. ☸️

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We’re actually simply beginning out.

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Let’s set it up 🚀

We’ll begin by initializing our mission with:

npm init -y

This initializes a NodeJS mission with the bundle.json 📝 file which retains monitor of our put in dependencies.

Set up Categorical.js framework

npm set up categorical

Now, contained in the bundle.json the dependencies object ought to look one thing like this. ✅

  "dependencies": {
    "categorical": "^4.18.2"
  }

Now, on the root of the mission create an index.js file and add the next traces of code. 🚀

// 👇🏻 Initialize categorical.
const categorical = require("categorical");
const app = categorical();

const port = 3000;

// 👇🏻 Return a pattern JSON object with a message property on the foundation path.
app.get("/", (req, res) => {
  res.json({
    message: "Good day from Odigos!",
  });
});

// 👇🏻 Pay attention on port 3000.
app.pay attention(port, () => {
  console.log(`Server is listening on port ${port}`);
});

We have to add a script in our bundle.json for operating the applying. Add it throughout the scripts object of bundle.json.

  "scripts": {
    "dev": "node index.js"
  },

Now, to examine our utility is operating correctly, run the server utilizing npm run dev and make a get request to localhost:3000 both by way of CLI or within the browser. ✨

In case you are utilizing CLI, make sure that to have cURL put in. ✅

curl http://localhost:3000

It’s best to see one thing like this. 👇🏻

Now, you’ll be able to merely cease the operating categorical server utilizing Ctrl + C 🚫

Our pattern utility is prepared! 🎉 Now, let’s containerize it and push it to Kubernetes. 🐳☸️

Containerize the applying 📦

We shall be utilizing Docker to containerize our utility.
Within the root of the mission, create a brand new file named Dockerfile.

💡 Be sure that to precisely identify it the identical. In any other case, you will have to explicitly cross the -f flag for specifying the Dockerfile path.

# Makes use of node as the bottom picture
FROM node:21-alpine 
# Units up our working listing as /app contained in the container.
WORKDIR /app
# Copyies bundle json information.
COPY bundle.json package-lock.json ./
# Installs the dependencies from the bundle.json
RUN npm set up --production
# Copies present listing information into the docker atmosphere
COPY . .
# Expose port 3000 as our server makes use of it.
EXPOSE 3000
# Lastly runs the server.
CMD ["node", "index.js"]

Now, we have to construct ⚒️ this container to have the ability to truly use it and push it to Kubernetes.

Run this command to construct the Dockerfile.

🚨 In case you are operating it on Home windows, make sure that to have Docker Desktop operating.

// 👇🏻 We're tagging our picture identify to express-server
docker construct -t express-server .

Now, it is time to run the container. 🏃🏻‍♂️💨

docker run -dp 127.0.0.1:3000:3000 express-server

💡 We’re operating our container within the background with the container port 3000 mapping to our pc port 3000.

As soon as once more run the next command and you must see the identical consequence as earlier. ✅

curl http://localhost:3000

NOTE: This time the applying is just not operating on our pc as earlier than. As a substitute, it’s operating contained in the container. 🤯

Deploying in Kubernetes ⚓

As stated earlier, we are going to use Minikube to create an orchestration atmosphere in our native pc and use kubectl command to work together with Kubernetes. 😄

Begin Minikube: 🚀

minikube begin

Since we’re going to be utilizing native containers as an alternative of pulling them from the docker hub, run these instructions. ✨

eval $(minikube docker-env)
docker construct -t express-server .

eval $(minikube docker-env): It’s used to level your terminal’s docker-cli to the Docker Engine inside minikube.

🚨 Observe, many people use Fish as our shell, so for fish the corresponding command could be eval (minikube docker-env)

Now, within the mission root, create a nested folder k8/deployment, and contained in the deployment folder, create a brand new file referred to as deployment.yaml with the next content material.

On this file, we are going to handle the deployment of our container. 👇🏻

# 👇🏻 /k8/deployment/deployment.yaml
apiVersion: apps/v1
variety: Deployment
metadata:
  identify: express-deployment
spec:
  selector:
    matchLabels:
      app: express-svr
  template:
    metadata:
      labels:
        app: express-svr
    spec:
      containers:
        - identify: express-svr
          picture: express-server
          imagePullPolicy: By no means # Be sure that to set it to By no means, or else it would pull from the docker hub and fail.
          sources:
            limits:
              reminiscence: "128Mi"
              cpu: "500m"
          ports:
            - containerPort: 3000

Lastly, run this command to use the deployment configuration we simply created, deployment.yaml. ✨

kubectl apply -f .ok8deploymentdeployment.yaml

Now, if we check out the operating pods we will see that the pod has efficiently been created. 🎉

To view the logs of our created pod, run kubectl logs <pod_name> and we must always see the next.

With this, our express-server is efficiently deployed on an area Kubernetes. 😎

That’s it for this text, we efficiently containerized our utility and deployed it to Kubernetes.

The supply code for this text could be discovered right here
https://github.com/keyval-dev/blog/tree/main/js-on-k8s

Thanks a lot for studying! 🎉🫡