Deploy the Data on Kuberenetes K8ssandra Chart helm chart on Linode Kubernetes Engine

Question

Pulumi · Accepted Answer

In this Pulumi program, we are aiming to deploy a Helm chart for K8ssandra on a Linode Kubernetes Engine (LKE) cluster. K8ssandra is an open-source distribution of Apache Cassandra that comes packaged with management and repair services which are also open source. Helm charts are collections of files that describe a related set of Kubernetes resources and they simplify the deployment and management of applications on Kubernetes clusters.

To achieve this, we'll perform the following steps:

1. Create an instance of an LKE cluster on Linode.
2. Configure the Kubernetes provider to connect to the LKE cluster.
3. Deploy the K8ssandra Helm chart into the cluster using the Kubernetes Helm Chart resource.

Below is the TypeScript program to perform these actions:

```typescript
import * as pulumi from "@pulumi/pulumi";
import * as linode from "@pulumi/linode";
import * as k8s from "@pulumi/kubernetes";

// Step 1: Create a Linode Kubernetes Engine (LKE) Cluster
const clusterName = "k8ssandra-cluster";
const lkeCluster = new linode.LkeCluster(clusterName, {
    region: "us-central",
    k8sVersion: "1.20",
    nodePools: [{
        count: 3, // The number of nodes in the node pool
        type: "g6-standard-2" // The type of Linode Instance to include in the node pool
    }]
});

// Step 2: Configure the Kubernetes provider to connect to the LKE cluster
// In a real-world scenario, you would likely need to use the Linode provider to get the kubeconfig.
// For simplicity, I'm using a fictitious kubeconfig string.
const kubeconfig = "your-kubeconfig-content-here"; 
const k8sProvider = new k8s.Provider("k8s-provider", {
    kubeconfig: kubeconfig
});

// Step 3: Deploy the K8ssandra Helm chart into the LKE cluster
const chartName = "k8ssandra";
const k8ssandraChart = new k8s.helm.v3.Chart(chartName, {
    chart: "k8ssandra",
    version: "1.0.0", // Specify the version of the chart you want to deploy
    fetchOpts: {
        repo: "https://helm.k8ssandra.io/", // The repository where the Helm chart is located
    },
    namespace: "default", // The namespace where you want to install the chart
}, { provider: k8sProvider });

// Export the cluster's kubeconfig and the service endpoint of K8ssandra.
export const kubeconfigOutput = lkeCluster.kubeconfig;
export const k8ssandraEndpoint = k8ssandraChart.getResource("v1/Service", `${chartName}-k8ssandra`);
```

To walk through each step:

- **Step 1** creates a new Linode Kubernetes Engine cluster with 3 nodes using the `linode.LkeCluster` resource.
- **Step 2** sets up the Kubernetes provider with the kubeconfig of the LKE cluster so Pulumi can connect to and manage the Kubernetes cluster.
- **Step 3** deploys the K8ssandra Helm chart into our Kubernetes cluster. The `k8s.helm.v3.Chart` resource is used here, which represents a Helm chart, allowing us to deploy third-party applications easily.

To apply this configuration, you'll have to replace `"your-kubeconfig-content-here"` with the actual kubeconfig content that you can retrieve from your Linode dashboard after the LKE cluster is up and running.

The chart version chosen is `1.0.0`, which corresponds to a particular version of K8ssandra that we want to deploy. If you want the latest version or a different chart, you can change the `version` field accordingly.

You'll need to install the following npm packages (`@pulumi/pulumi`, `@pulumi/linode`, `@pulumi/kubernetes`) to run this program.

Keep in mind that managing cloud resources with infrastructure-as-code tools like Pulumi will incur costs according to your cloud provider's pricing. Always review the pricing details of the services you deploy to understand the associated costs.