Deploy the terraform-backend helm chart on Oracle Kubernetes Engine (OKE)

Question

Pulumi · Accepted Answer

To deploy the `terraform-backend` Helm chart on Oracle Kubernetes Engine (OKE) using Pulumi, you need to perform a series of steps. First, you'll ensure you have the Oracle Cloud Infrastructure (OCI) provider configured, which will let you work with resources within Oracle Cloud. Then, you'll set up a Kubernetes cluster using the OKE-related resources, if you don't already have one. After that, you will use the `kubernetes` package to deploy a Helm chart to the cluster.

Below is a program written in TypeScript that accomplishes these tasks. This program is divided into two parts:

1. Provisioning the OKE Kubernetes cluster using OCI resources (if necessary). I'll assume you have a pre-existing cluster for the sake of this example. Please make sure you replace the placeholder values with the actual values from your Oracle Cloud environment.
   
2. Deploying the `terraform-backend` Helm chart to the OKE cluster using the Pulumi Kubernetes provider.

In this example, we are assuming that we do not have to create a new OKE cluster since it requires setting up networking and other components which are beyond the scope of this deployment. 
We will focus on deploying a Helm chart assuming that an OKE cluster and the required `kubeconfig` file are already available.

Here is a Pulumi TypeScript program that deploys a Helm chart to an OKE cluster:

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

// You should configure your Oracle Cloud Infrastructure provider and Kubernetes provider.
// Ensure that your Pulumi configuration is correctly set up to interact with your OCI account.

// Load the kubeconfig file from the file system. You need to replace `path-to-kubeconfig-file`
// with the actual path to your kubeconfig file that was generated when you created the OKE cluster.
const kubeconfig = pulumi.output(pulumi.fs.readFile("path-to-kubeconfig-file"));

// Create a Kubernetes provider instance using the above kubeconfig.
const k8sProvider = new k8s.Provider("oke-k8s", {
    kubeconfig: kubeconfig,
});

// Deploy the `terraform-backend` Helm chart to the OKE cluster.
const terraformBackendChart = new k8s.helm.v3.Chart("terraform-backend", {
    chart: "terraform-backend",
    // The `repo` field should point to the Helm repository URL that hosts the `terraform-backend` chart.
    // Replace `REPO_URL` below with the URL of the repository.
    repo: "REPO_URL",
    version: "CHART_VERSION", // Replace `CHART_VERSION` with the version of the Helm chart you wish to deploy.
    // In case you need to provide custom values to your Helm chart, use the `values` field.
    values: {
        // Replace the values below with the required ones for the `terraform-backend` Helm chart.
        storage: {
            size: "10Gi",
            // More custom values can be added here.
        },
        // You can also specify other configuration parameters required by the `terraform-backend` chart here.
    },
}, { provider: k8sProvider });

// Export the frontend and backend hostnames so we can easily access them.
export const backendUrl = terraformBackendChart.getResourceProperty("v1/Service", "terraform-backend", "status")
    .apply(status => `http://${status.loadBalancer.ingress[0].ip}`);
```

In this code:

- We load the Kubernetes configuration from a `kubeconfig` file that allows Pulumi to communicate with your OKE cluster.
- We instantiate a Pulumi Kubernetes provider using this configuration.
- We use the `k8s.helm.v3.Chart` resource to deploy the `terraform-backend` Helm chart to the cluster. 
  - Replace `REPO_URL` with the Helm repository containing the `terraform-backend` chart. If this chart is hosted in a Helm chart repository provided by Oracle, you would replace `REPO_URL` with the appropriate Oracle Helm repository URL.
  - The `CHART_VERSION` should be replaced with the version number of the `terraform-backend` Helm chart you want to deploy.
  - The `values` property is where you can specify custom configuration for the Helm chart deployment.
- We also export the URL where the `terraform-backend` service can be accessed after it's exposed by the LoadBalancer.

Please replace the placeholders `REPO_URL`, `CHART_VERSION`, and `path-to-kubeconfig-file` with the actual values specific to your setup.

This program should be executed within a Pulumi project. To run this Pulumi program, you need to have Pulumi installed and configured to access your OCI account, Docker Hub, and any other services your application may interact with.

Set up the project, install the necessary dependencies with `npm` or `yarn`, and then run `pulumi up` to deploy the Helm chart to your OKE cluster. After the deployment is complete, you can access the Terraform backend using the outputted backend URL.