Deploy the squareone helm chart on Linode Kubernetes Engine

Question

Pulumi · Accepted Answer

When you want to deploy a Helm chart to a Kubernetes cluster using Pulumi, you'll typically need to do the following:

1. Set up the Kubernetes cluster where you will deploy the Helm chart.
2. Configure Pulumi to manage resources in that cluster.
3. Use Pulumi's `Chart` resource from the Kubernetes provider to deploy the Helm chart to your cluster.

For this case, we assume that you have already provisioned a Linode Kubernetes Engine (LKE) cluster and have the `kubeconfig` file available to interact with your Kubernetes cluster.

You'll begin by installing the needed Pulumi packages. For TypeScript, you use `npm` to install packages:

```shell
npm install @pulumi/pulumi @pulumi/kubernetes
```

Then, you can write a Pulumi program to deploy the Helm chart. Below is a TypeScript program that accomplishes this. The `Chart` resource is a component resource that encapsulates deploying the Helm chart from a repository.

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

// You must be authenticated with your Kubernetes cluster
// Pulumi uses the kubeconfig file to communicate with the cluster
const kubeconfig = process.env.KUBECONFIG;

// Create a Kubernetes provider instance using the kubeconfig from Linode
const provider = new k8s.Provider("lke-k8s-provider", {
    kubeconfig: kubeconfig,
});

// Deploy the "squareone" Helm chart into the Kubernetes cluster
const squareoneChart = new k8s.helm.v3.Chart("squareone", {
    chart: "squareone", // Name of the Helm chart
    version: "1.0.0",   // Version of the Helm chart, specify the version you need
    // If the chart is from a custom repository, you can specify it like this
    // repo: "http://charts.example.com/",
    // You can pass configuration values for the Helm chart like this
    // values: {
    //   service: {
    //     type: "LoadBalancer",
    //   },
    // },
}, { provider });

// Export the endpoint of the deployed application/service
export const squareoneEndpoint = squareoneChart.getResourceProperty("v1/Service", "squareone-service", "status").apply(status => status.loadBalancer.ingress[0].ip);

```

To apply this deployment, run `pulumi up` in the terminal, and the Pulumi CLI will provision the resources as described.

Let's break down what's happening:

- `kubeconfig` variable is used to store the path to your `kubeconfig` file, which allows Pulumi to authenticate with your LKE cluster.
- A Kubernetes provider instance is set up to interface with your cluster.
- A `Chart` resource is declared with `new k8s.helm.v3.Chart`. This is where you specify the Helm chart name, version, and custom values, if any. If your Helm chart is in a custom repository, you would include the `repo` property and set it to your chart's repository URL.
- Additionally, a `provider` option is passed to the `Chart` resource to specify which Kubernetes provider to use.
- Finally, an export is included to provide the endpoint of the application once it's deployed, assuming your chart creates a `Service` resource with the type `LoadBalancer`.

Remember, this program assumes that the Helm chart "squareone" exists and is publicly available. If it's a private chart or hosted in a custom Helm repository, additional configuration would be necessary. Also, if the Helm chart requires setting custom values, you would include a `values` field with an object representing those values.