Deploy the istio-release-operator helm chart on Kubernetes

Question

Pulumi · Accepted Answer

To deploy the `istio-release-operator` Helm chart on Kubernetes using Pulumi, we will use the `kubernetes.helm.v3.Chart` resource from the Pulumi Kubernetes provider. This resource allows you to declare a Helm chart to be installed into your Kubernetes cluster.

First, make sure you have:
1. Pulumi CLI installed and set up. You can find instructions on installing Pulumi [here](https://www.pulumi.com/docs/get-started/install/).
2. Kubernetes cluster running and `kubectl` is correctly configured to connect to your cluster.
3. Have access to the Helm chart repository where `istio-release-operator` is located.

Here's how you can deploy the `istio-release-operator` Helm chart:

1. **Import Necessary Packages**: We start by importing the `@pulumi/kubernetes` package which provides the necessary methods to interact with Kubernetes and deploy Helm charts.

2. **Create a Helm Chart Resource**: The `kubernetes.helm.v3.Chart` class is instantiated to create the Helm chart resource. This class takes the chart name, and additional options such as the repository where the chart is hosted, the version of the chart to deploy, and any custom values you want to specify for your Istio operator configuration.

3. **Provide Configuration Values**: Helm charts may require or allow configuration options to be specified. You can provide these as an object with keys and values matching the chart’s values.yaml file. If you have a custom `values.yaml` file, you can also read it and provide its contents.

Here is the TypeScript code that accomplishes this:

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

// Define the name of the chart and the repository details.
const chartName = "istio-operator";
const chartRepo = "https://istio-release.storage.googleapis.com/charts";
const chartVersion = "x.y.z"; // Replace with a specific chart version.

// Optional: Specify the custom values you want to use for this deployment.
// Replace the values below with the ones appropriate for your deployment.
const customValues = {
  // Lots of possible customizations, depending on your requirements.
  // Reference the istio-operator's values.yaml for available options.
  // Example:
  // pilot: {
  //   autoscaleEnabled: true,
  //   traceSampling: 1.0,
  // }
};

// Deploying the chart to the Kubernetes cluster.
const istioReleaseOperatorChart = new kubernetes.helm.v3.Chart(chartName, {
  chart: chartName,
  version: chartVersion,
  fetchOpts: {
    repo: chartRepo,
  },
  values: customValues,
});

// Export any required resource details, such as an endpoint.
export const istioOperatorEndpoint = "check-istio-operator-endpoint"; // Replace with a real endpoint or value if necessary.
```

The `fetchOpts` block inside the `Chart` class constructor is where you specify the Helm repository containing the `istio-release-operator` chart. You also specify the chart version you wish to deploy with `chartVersion`. If you don't specify a version, Pulumi will by default choose the latest one available.

The `values` field is an object that specifies configuration overrides that align with the options provided by the chart's `values.yaml`. For each field in the Helm chart's `values.yaml`, you can provide a corresponding key-value pair in the `customValues` object.

Once you run this Pulumi program with `pulumi up`, it will reach out to the specified Helm repository, pull the chart, and apply it to your Kubernetes cluster taking into account all the custom values you have defined.

When deploying Helm charts that are critical pieces of cluster infrastructure like the Istio operator, you should ensure you're pinning to a specific version of the chart, as represented by `chartVersion`, to maintain consistency and predictability.

After the `pulumi up` command completes, it will show you any resources that were created or modified during the deployment. The export at the bottom is a placeholder where you could export certain output parameters of the deployment, such as the endpoint for the Istio operator if applicable.

Keep in mind that deploying Istio into a cluster can involve more configuration options based on your specific needs. It’s important to tailor the `customValues` to match the recommendations for your particular use case. Always refer to the official Istio documentation when deciding on these values.