Deploy the rke2-flannel helm chart on Digital Ocean Kubernetes Service

Question

Pulumi · Accepted Answer

To deploy the RKE2-Flannel Helm chart on the Digital Ocean Kubernetes Service, you can use Pulumi to programmatically define, deploy, and manage this infrastructure. Pulumi allows you to define your infrastructure as code in familiar programming languages like TypeScript.

Here's how you can do it:

1. First, you need to create a Kubernetes cluster in Digital Ocean using Pulumi's DigitalOcean provider.
2. Then, you install the RKE2-Flannel Helm chart into this cluster using the Pulumi Kubernetes provider's Helm chart resource.

Below is a TypeScript program that demonstrates how you can achieve this with Pulumi:

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

// Create a DigitalOcean Kubernetes cluster
const cluster = new digitalocean.KubernetesCluster("do-cluster", {
    region: "nyc3",
    version: "latest",
    nodePool: {
        name: "default",
        size: "s-2vcpu-2gb",
        nodeCount: 2,
    },
});

// Export the DigitalOcean Kubernetes config
export const kubeConfig = cluster.kubeConfigs[0].rawConfig;

// Use the kubeconfig to create a provider instance
const k8sProvider = new k8s.Provider("k8s-provider", {
    kubeconfig: kubeConfig,
});

// Deploy the RKE2-Flannel Helm chart
const chart = new k8s.helm.v3.Chart("rke2-flannel", {
    chart: "rke2-flannel",
    version: "0.1.0", // specify the exact chart version to use
    fetchOpts: {
        repo: "https://helm.rke2.io/", // the repository where the chart is located
    },
}, { provider: k8sProvider });

// Export the Kubernetes cluster name and status
export const clusterName = cluster.name;
export const clusterStatus = cluster.status;
```

Here's what's happening in the code above:

- We import necessary packages from the Pulumi library.
- We create a new DigitalOcean Kubernetes cluster using `new digitalocean.KubernetesCluster`.
  - `region`: Specifies the region where the Kubernetes cluster will be located.
  - `version`: The version of Kubernetes to deploy; setting "latest" will use the latest version available in that region on DigitalOcean.
  - `nodePool`: Defines the size and the count of nodes for the cluster.
  
- We then export the configuration file required to connect to the Kubernetes cluster.
- Using the exported kubeconfig, we create a new instance of the Pulumi Kubernetes provider. This provider will be used to connect to the created Kubernetes cluster for deploying workloads.
- Next, we define the Helm chart `rke2-flannel` using `new k8s.helm.v3.Chart`.
  - `chart`: The name of the Helm chart within the repo.
  - `version`: The version number of the Helm chart to deploy. It is good practice to pin this to a specific version for consistent deployments.
  - `fetchOpts`: An object containing the repo URL where the Helm chart is hosted.
  
- The chart is then deployed to the Kubernetes cluster by associating it with the previously created k8s provider.
- Finally, we export the cluster name and status as outputs. These can be viewed after deployment using the Pulumi CLI.

To run this program, you need to have Pulumi CLI installed and configured for use with your DigitalOcean account, and then execute the `pulumi up` command to initiate the creation and deployment process. This will create the Kubernetes cluster in DigitalOcean and deploy the RKE2-Flannel Helm chart to it.