Deploy the fluentd-kubernetes-daemonset helm chart on Digital Ocean Kubernetes Service

Question

Pulumi · Accepted Answer

Deploying a Helm chart to a Kubernetes cluster involves several steps: setting up the cluster itself, and then using a package manager (like Helm) to deploy applications or services to that cluster. In this case, we will be setting up a Digital Ocean Kubernetes (DOKS) cluster and deploying the Fluentd daemonset using Helm.

Here's how the deployment process generally works:

1. **Provisioning the DOKS Cluster**: This involves creating a Kubernetes cluster on Digital Ocean's cloud platform. We will use Pulumi's Digital Ocean (`digitalocean`) provider to create this cluster.
   
2. **Installing the Helm Chart**: Once the cluster is running, we will install the Fluentd daemonset using a Helm chart. For this, we'll use Pulumi's `kubernetes` provider, which allows us to utilize Helm charts directly through Pulumi without needing the Helm CLI tool.

Let's now go through the Pulumi TypeScript program for these steps:

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

// Step 1: Provision the Digital Ocean Kubernetes Service (DOKS)

// Create a new Digital Ocean Kubernetes cluster
const cluster = new digitalocean.KubernetesCluster("my-doks-cluster", {
    region: digitalocean.Regions.NYC1,  // Be sure to choose a region that supports DOKS
    version: "latest",  // This will use the latest Kubernetes version supported by DOKS
    nodePool: {
        size: digitalocean.DropletSlugs.Docs2Vcpu4Gb,  // Droplet size for worker nodes
        name: "default",
        nodeCount: 2,  // Number of worker nodes
    },
});

// Step 2: Install Fluentd with a Helm chart onto the DOKS cluster

// Use the created DOKS cluster kubeconfig for the Pulumi Kubernetes provider
const k8sProvider = new kubernetes.Provider("k8s-provider", {
    kubeconfig: cluster.kubeConfigs[0].rawConfig,
});

// Install the Fluentd Helm chart
const fluentd = new kubernetes.helm.v3.Chart("fluentd", {
    chart: "fluentd",
    version: "0.2.0",  // Specify the chart version; adjust this as needed
    fetchOpts: {
        repo: "https://charts.fluentbit.io/",  // The repository containing the Fluentd chart
    },
}, { provider: k8sProvider });

// Expose the cluster endpoint and kubeconfig for easy access
export const kubeconfig = cluster.kubeConfigs[0].rawConfig;
export const clusterEndpoint = cluster.endpoint;
```

Here, we defined a new Kubernetes cluster in Digital Ocean and named it `my-doks-cluster`. We specified a region, the Kubernetes version, and details for the node pool, including droplet size and node count.

After the cluster is provisioned, we create a Pulumi Kubernetes provider with the kubeconfig returned from the Digital Ocean cluster, which allows Pulumi to communicate with our cluster.

With the Kubernetes provider configured, we deploy Fluentd using the Helm chart by referencing it and passing any applicable configurations, like the chart version and the repository URL.

The `kubeconfig` and `clusterEndpoint` are being exported; they can be used to interact with your Kubernetes cluster via `kubectl` or other Kubernetes tools.

To execute this Pulumi code:
1. Save the code in a file with the `.ts` extension (for TypeScript), such as `index.ts`.
2. Ensure you have Pulumi installed and configured for use with your Digital Ocean account.
3. Run `pulumi up` in the directory where your file is located. This will provision the resources on Digital Ocean.

Please replace `"latest"` and `"0.2.0"` with the specific versions of Kubernetes and Fluentd helm chart that you want to use. This is important because the "latest" keyword can refer to different versions at different times, and it's a best practice to lock into a specific version for repeatable deployments.

Remember to manage the Digital Ocean resources you created responsibly, removing them with `pulumi destroy` when they're no longer needed to avoid unnecessary charges.