Deploy the kube-metrics-adapter helm chart on Digital Ocean Kubernetes Service

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Pulumi · Accepted Answer

To deploy the `kube-metrics-adapter` Helm chart on a Digital Ocean Kubernetes Service (DOKS) with Pulumi, you will be doing the following steps:

1. **Create a Digital Ocean Kubernetes Cluster**: You'll set up a DOKS cluster, which is a managed Kubernetes service provided by Digital Ocean.

2. **Install the kube-metrics-adapter Helm Chart**: Using Pulumi's Kubernetes provider, you'll deploy the `kube-metrics-adapter` Helm chart to the DOKS cluster. Helm is a package manager for Kubernetes, and Helm charts are packages of pre-configured Kubernetes resources.

Below is a Pulumi TypeScript program that accomplishes these tasks. The program is structured into two main parts: the cluster creation and the Helm chart deployment. After the cluster is provisioned, Pulumi can install the Helm chart into the cluster.

To work with Digital Ocean, Pulumi uses the `@pulumi/digitalocean` package. For working with Kubernetes resources, including Helm charts, Pulumi uses the `@pulumi/kubernetes` package.

Please ensure you have the following prerequisites before running the code:
- Pulumi CLI installed.
- Digital Ocean access token and Kubernetes configuration set up in your Pulumi environment.
- The appropriate Pulumi stack selected or a new one created for this deployment.

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

// Create a Digital Ocean Kubernetes cluster
const cluster = new digitalocean.KubernetesCluster("doks-cluster", {
    region: "nyc1", // Choose the region according to your preference
    version: "latest", // Use the latest available version of Kubernetes
    nodePool: {
        name: "default",
        size: "s-2vcpu-2gb", // Choose the node size that best fits your needs
        nodeCount: 2, // Number of nodes in the node pool
    },
});

// Export the kubeconfig to access the cluster with kubectl
export const kubeconfig = cluster.kubeConfigs[0].rawConfig;

// Deploy the kube-metrics-adapter Helm chart to the DOKS cluster
const kubeMetricsAdapterChart = new k8s.helm.v3.Chart("kube-metrics-adapter-chart", {
    chart: "kube-metrics-adapter",
    fetchOpts: {
        repo: "https://kedacore.github.io/charts", // Replace with the repository containing kube-metrics-adapter
    },
    namespace: "kube-system", // Deploy the chart in the kube-system namespace (or choose a different namespace)
    // Values to override chart defaults if necessary
    values: {},
}, {
    provider: new k8s.Provider("k8s-provider", {
        kubeconfig: kubeconfig,
    }),
});

// Export the Helm chart deployment status
export const helmDeploymentStatus = kubeMetricsAdapterChart.status;

// To apply this program to your Digital Ocean account:
// Run `pulumi up` and follow the on-screen prompts.
```

This Pulumi program starts by importing the necessary Pulumi libraries for Digital Ocean and Kubernetes. Then, it defines a new Digital Ocean Kubernetes cluster. After the cluster creation, Pulumi exports the `kubeconfig`, which is needed to interact with the cluster (e.g., using `kubectl`).

Next, the program deploys the `kube-metrics-adapter` Helm chart to the created DOKS cluster using Pulumi's Kubernetes provider, `@pulumi/kubernetes`. Notice the `provider` property in the Helm chart resource which specifies that the Helm chart should be deployed using the kubeconfig from the Digital Ocean cluster you just created.

Lastly, the program exports a `helmDeploymentStatus` variable, which will display the status of the Helm chart deployment once the Pulumi program is executed.

To run this Pulumi program:
- Install the required packages: `npm install @pulumi/pulumi @pulumi/digitalocean @pulumi/kubernetes`
- Save the above TypeScript code in a file called `index.ts`.
- Execute `pulumi up` using the Pulumi CLI, review the proposed infrastructure changes, and confirm the deployment.

Once the deployment is successful, you will have a Digital Ocean Kubernetes cluster with the `kube-metrics-adapter` installed. You can use the exported kubeconfig to interact with your cluster and validate the Helm chart deployment.