Deploy the Data on Kuberenetes K8ssandra Chart helm chart on Google Kubernetes Engine (GKE)

Question

Pulumi · Accepted Answer

To deploy the DataStax Kubernetes K8ssandra chart on Google Kubernetes Engine (GKE), you'll first need to set up a GKE cluster and configure your environment to use Helm, a package manager for Kubernetes that streamlines installing and managing Kubernetes applications. K8ssandra is a Helm chart that packages all the components you'll need for deploying Apache Cassandra on Kubernetes along with management and monitoring tools.

Here is a detailed walkthrough of a Pulumi TypeScript program that accomplishes this:

1. **Set up the GKE cluster**: You will utilize the `google-native.container/v1.Cluster` resource to create a new Google Kubernetes Engine cluster.
2. **Create a Kubernetes Provider**: Once the GKE cluster is created, we’ll instantiate a Kubernetes provider to interact with it.
3. **Use the Helm Chart Resource**: With both the GKE cluster and the Kubernetes provider set up, you can use the `kubernetes.helm.v3.Chart` resource from Pulumi’s Kubernetes provider to deploy the K8ssandra Helm chart.

Below you will find the complete TypeScript program that performs these steps:

```typescript
import * as pulumi from '@pulumi/pulumi';
import * as gcp from '@pulumi/gcp';
import * as k8s from '@pulumi/kubernetes';

// Step 1: Create a new GKE cluster
const cluster = new gcp.container.Cluster("k8ssandra-cluster", {
    initialNodeCount: 3,
    minMasterVersion: "latest",
    nodeVersion: "latest",
    nodeConfig: {
        preemptible: false,
        machineType: "n1-standard-2",
        oauthScopes: [
            "https://www.googleapis.com/auth/compute",
            "https://www.googleapis.com/auth/devstorage.read_only",
            "https://www.googleapis.com/auth/sqlservice.admin",
            "https://www.googleapis.com/auth/service.management.readonly",
            "https://www.googleapis.com/auth/servicecontrol",
            "https://www.googleapis.com/auth/logging.write",
            "https://www.googleapis.com/auth/monitoring",
        ],
    },
});
// Output the GKE cluster name
export const k8sClusterName = cluster.name;

// Step 2: Create a Kubernetes provider that uses the GKE cluster
const k8sProvider = new k8s.Provider("k8sProvider", {
    kubeconfig: cluster.kubeConfigRaw,
});

// Step 3: Deploy K8ssandra Helm chart using Pulumi's Helm Chart resource
const chart = new k8s.helm.v3.Chart("k8ssandra", {
    chart: "k8ssandra",
    version: "3.11.11", // specify the version you need for K8ssandra
    fetchOpts: {
        repo: "https://helm.k8ssandra.io/",
    },
}, { provider: k8sProvider });

// Export the Helm chart name
export const k8ssandraHelmChart = chart.getResource("v1/Service", "k8ssandra-k8ssandra");
```

### Explanation of the program:

- **GKE Cluster**: The `gcp.container.Cluster` resource is used to create a cluster in GKE. We specify the number of nodes, machine type, and OAuth scopes. This cluster will then run the K8ssandra chart.

- **Kubernetes Provider**: The `k8s.Provider` resource points Pulumi to the cluster we’ve created, so subsequent resources will be deployed there.

- **Helm Chart**: The `k8s.helm.v3.Chart` resource is responsible for fetching the K8ssandra chart from the provided Helm repository and deploying the chart into the GKE cluster.

- **Exported Values**: We export the cluster name and the Service associated with the K8ssandra Helm chart so that you can easily access these values from the Pulumi stack.

### Post-deployment:

After running the Pulumi program with `pulumi up`, Pulumi will provision the GKE cluster and deploy the K8ssandra Helm chart onto it. It might take a few minutes for everything to get set up.

Once complete, you can verify the status of your GKE cluster and the K8ssandra Helm release:

1. Check the GKE cluster in the Google Cloud Console.
2. Use `kubectl` to list all the resources deployed by the K8ssandra Helm chart to ensure they're running.

Remember to install `kubectl` and configure it to connect to your new GKE cluster if you want to interact with your Kubernetes resources manually. You can find the `kubeconfig` needed for this in the output of your Pulumi deployment or by using the Google Cloud CLI.