Deploy the zipkin-gcp helm chart on Digital Ocean Kubernetes Service

Question

Pulumi · Accepted Answer

Deploying a Helm chart to a Kubernetes cluster hosted on Digital Ocean entails several steps using Pulumi. First, we will create a Kubernetes cluster on Digital Ocean. Next, we will use the Helm chart resource to deploy the 'zipkin-gcp' chart to our cluster.

Below is a descriptive guide and a Pulumi TypeScript program that does just that.

### Prerequisites
Ensure that you have the following installed:
- Pulumi CLI
- Digital Ocean API Token: This token should be set as an environment variable named `DIGITALOCEAN_TOKEN`.

### Creating the Digital Ocean Kubernetes Cluster
We will create a new Kubernetes cluster within a specified region using the `digitalocean.KubernetesCluster` resource. For the node pool, we configure a set of specifications like the node size, which indicates the droplet size, and the node count, which is the number of droplets to create.

### Deploying the Helm Chart
With the cluster in place, we proceed to deploy the Helm chart. Pulumi provides us with the `kubernetes.helm.v3.Chart` resource, which represents a Helm chart in a Kubernetes cluster.

We will deploy the 'zipkin-gcp' Helm chart. Pulumi will need access to your Kubernetes cluster to manage resources. This typically involves setting up the KUBECONFIG environment variable or using the kubeconfig file generated by Digital Ocean once the cluster is provisioned.

### Pulumi Program for Deployment
Here is the full TypeScript program for deploying the 'zipkin-gcp' Helm chart on a Digital Ocean Kubernetes cluster.

```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("zipkin-cluster", {
    region: digitalocean.Regions.SFO2,
    version: "1.21.5-do.0",
    nodePool: {
        name: "zipkin-nodepool",
        size: digitalocean.DropletSlugs.DropletS2VCPU2GB,
        nodeCount: 2,
    },
});

// Export the DigitalOcean Kubeconfig
export const kubeconfig = cluster.kubeConfigs[0].rawConfig;

// Deploy the 'zipkin-gcp' Helm chart to the cluster.
const zipkinChart = new k8s.helm.v3.Chart("zipkin-gcp", {
    chart: "zipkin-gcp",
    version: "0.1.0", // Replace with the actual chart version you wish to deploy
    fetchOpts: {
        repo: "https://helm.repo.url", // Replace with the actual Helm chart repository URL
    },
}, { provider: new k8s.Provider("k8s-provider", { kubeconfig: cluster.kubeConfigs[0].rawConfig }) });

// Export the Helm chart resources
export const chart = zipkinChart.resources;
```

### Explanation
- `cluster`: Represents our Kubernetes cluster managed by the Digital Ocean provider. We specify the region, version, and node pool details.
- `kubeconfig`: We are exporting the kubeconfig of the created cluster. This is the configuration required by Kubernetes clients to connect to the cluster.
- `zipkinChart`: We define a Helm chart resource pointing to the 'zipkin-gcp' chart. We need to specify the version and repository where the Helm chart is located. Replace placeholder strings with actual values.
- `provider`: We create a Kubernetes provider instance using the kubeconfig from our Digital Ocean cluster. This allows Pulumi to communicate with our cluster and manage resources.
- `chart.resources`: We export the resources created as part of the Helm chart deployment for later reference or inspection.

### Deploying the Program
To deploy the program, follow these steps:
1. Save the above code to a file named `index.ts`.
2. Run `pulumi up` to preview and deploy the changes.

Pulumi will handle the necessary steps to set up the Kubernetes cluster and deploy the Zipkin chart.