Deploy the application-component helm chart on Rancher

Question

Pulumi · Accepted Answer

Deploying a Helm chart on a Rancher-managed Kubernetes cluster involves several steps. Rancher is a complete container management platform that makes it easy to manage Kubernetes clusters across different infrastructure. To deploy a Helm chart, you typically need to have access to a Rancher-managed Kubernetes cluster, and the Helm chart details like its name, version, repository, and any custom values you want to apply.

Below I'll demonstrate a Pulumi TypeScript program that accomplishes this. First, I will use the `rancher2` Pulumi package to interact with the Rancher API. We will define a `CatalogV2` resource that adds the Helm chart repository to Rancher. Then, we will create an `AppV2` resource that deploys the Helm chart from the catalog we added to a given namespace.

The `AppV2` isn't directly available in the Pulumi Registry snippet provided, but it is a part of the Rancher2 Pulumi provider which allows you to manage applications in the Rancher platform. This abstraction is used to represent a Helm chart deployment within Rancher. You typically need to supply details such as the project ID, cluster ID, chart name, version, and any values you wish to override.

Here is the TypeScript program that shows how to do this:

```typescript
import * as rancher2 from "@pulumi/rancher2";

// Replace these variables with actual values or retrieve them from Pulumi config
const chartName = "application-component"; // the Helm chart name
const chartVersion = "1.2.3"; // the version of the chart to deploy
const chartRepoUrl = "https://charts.example.com/"; // the URL of the Helm chart repository
const clusterId = "my-cluster-id"; // the ID of the Rancher-managed cluster where we want to deploy
const projectId = "my-project-id"; // the ID of the Rancher project

// Create a new Helm chart repository (Catalog V2) in Rancher
const appCatalog = new rancher2.CatalogV2("applicationComponentCatalog", {
  clusterId: clusterId,
  gitRepo: "https://git.rancher.io/charts", // replace with your repository URL, if different
  gitBranch: "main",  // use the branch of the repo where your charts are located
  name: "app-catalog", // name for the catalog resource
  // Additional catalog configuration goes here if necessary
});

// Deploy the specified Helm chart
const app = new rancher2.AppV2("applicationComponent", {
  clusterId: clusterId,
  projectId: projectId,
  chartName: chartName,
  // Referencing the catalog created earlier
  repoName: appCatalog.name,
  namespace: "default",  // specify the namespace to deploy the Helm chart into
  chartVersion: chartVersion,
  // You can set custom values by specifying here
  // values: "<custom-values>",
  // Additional app configuration goes here if necessary
});

// Export the URL where the application will be accessible, if applicable
export const appUrl = app.status.url;
```

### Explanation:

1. **Catalog Resource**:
   - The `CatalogV2` resource is responsible for adding a Helm chart repository to Rancher.
   - This is similar to adding a repository in Helm using the `helm repo add` command.
   - We provide necessary details like `clusterId`, `gitRepo`, `gitBranch`, and a `name` for the catalog.

2. **Deploying the Chart**:
   - The `AppV2` resource represents the deployment of the Helm chart itself. 
   - It requires information about the cluster ID (`clusterId`), project ID (`projectId`), chart name (`chartName`), repository name (`repoName`), namespace, and chart version (`chartVersion`).
   - You can also pass in a string of custom values you would like to override in your Helm chart deployment through the `values` parameter.
   - As the `AppV2` resource isn't explicitly listed in the Pulumi Registry snippet, I've deduced from the context of the Rancher2 provider's capabilities. You may need to consult the [Rancher2 provider documentation](https://www.pulumi.com/registry/packages/rancher2/) for detailed information on its usage.

3. **Exports**:
   - An export statement `export const appUrl = app.status.url;` is used to output the URL at which the deployed application will be accessible. Note that this depends on whether the Helm chart service exposes any external endpoints.

Please ensure that you have the necessary permissions and configurations set up in Rancher and Pulumi to successfully run this program. This includes being authenticated with the Rancher server and having a Pulumi account and setup to manage state and perform deployments.