Deploy the prometheus-haproxy-exporter helm chart on Digital Ocean Kubernetes Service

Question

Pulumi · Accepted Answer

To deploy the `prometheus-haproxy-exporter` helm chart on Digital Ocean Kubernetes Service (DOKS), you'll be creating a Pulumi program in TypeScript. The program will perform the following steps:

1. Provision a DigitalOcean Kubernetes cluster using the `digitalocean.KubernetesCluster` resource.
2. Use the `kubernetes.helm.v3.Chart` resource from the Kubernetes provider to deploy the `prometheus-haproxy-exporter` helm chart on the cluster that's just been created.

Before you get started with the code, ensure you have installed Pulumi and have set up the necessary configuration for the DigitalOcean provider. This typically involves setting up the DigitalOcean Access Token in your environment variables or Pulumi configuration.

Here's a program that accomplishes the deployment:

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

// Create a new DigitalOcean Kubernetes cluster.
const cluster = new digitalocean.KubernetesCluster("do-cluster", {
    region: "nyc1",
    version: "latest",
    nodePool: {
        name: "default",
        size: "s-2vcpu-2gb",
        nodeCount: 2,
    },
});

// The kubeconfig can be used to connect to the cluster.
export const kubeconfig = cluster.kubeConfigs[0].rawConfig;

// Create a Kubernetes provider instance that uses our cluster kubeconfig.
const k8sProvider = new k8s.Provider("do-k8s-provider", {
    kubeconfig: kubeconfig,
});

// Deploy the `prometheus-haproxy-exporter` helm chart using the Kubernetes provider.
const helmChart = new k8s.helm.v3.Chart("haproxy-exporter", {
    chart: "prometheus-haproxy-exporter",
    version: "1.1.0", // specify the version you want to deploy
    namespace: "monitoring", // assuming you want to deploy this in the 'monitoring' namespace
    fetchOpts: {
        repo: "https://prometheus-community.github.io/helm-charts",
    },
}, { provider: k8sProvider });

// Export the chart name of the deployed Prometheus HAProxy Exporter.
export const haproxyExporterChartName = helmChart.chart;
```

### Explanation

- We import the `digitalocean` and `kubernetes` modules to interact with DigitalOcean and Kubernetes services.
- The `digitalocean.KubernetesCluster` resource creates a new DOKS cluster in the `nyc1` region, picks the latest Kubernetes version available on DigitalOcean, and specifies the node pool configuration (in this case, 2 nodes of size `s-2vcpu-2gb`).

[DigitalOcean KubernetesCluster Docs](https://www.pulumi.com/registry/packages/digitalocean/api-docs/kubernetescluster/)

- `kubeconfig` is exported, which holds the configuration needed to connect to your cluster with `kubectl` or any Kubernetes client. You’d use this to interact with your Kubernetes cluster once it's provisioned.
- A `k8s.Provider` is created with the obtained `kubeconfig`. This provider is used to deploy resources to your cluster.
- The `k8s.helm.v3.Chart` resource is then used to deploy the `prometheus-haproxy-exporter` helm chart to the Kubernetes cluster.

[Kubernetes Helm Chart Docs](https://www.pulumi.com/registry/packages/kubernetes/api-docs/helm/v3/chart/)

- The `repo` specified in `fetchOpts` is where Pulumi will fetch the Helm chart from. It's the official Helm chart repository for Prometheus.
- Optionally, you could customize the `values` property on the `Chart` resource to configure the HAProxy exporter according to your requirements, but it's omitted here for simplicity.
- At the end, we export some stack outputs for easy access to the deployed chart name and the `kubeconfig`.

Once you run this Pulumi program, it will provision a new Kubernetes cluster in Digital Ocean and deploy the `prometheus-haproxy-exporter` using the specified helm chart. You can retrieve the necessary output from the Pulumi stack to manage your deployment.