Deploy the tt-workflow helm chart on Rancher

Question

Pulumi · Accepted Answer

Deploying a Helm chart on Rancher using Pulumi involves several steps, including setting up Pulumi with the proper provider, creating an instance of Rancher, and deploying the Helm chart.

### Prerequisites
Before we begin, ensure that you have the following prerequisites:
1. An existing Rancher server or environment you can control.
2. Necessary permissions to create and manage resources in your Rancher environment.
3. Pulumi CLI installed on your machine.
4. Configured Pulumi to connect to your cloud provider.
5. Helm chart details of `tt-workflow`, i.e., the repository URL and chart version.

### Explanation
Firstly, we need the `rancher2` Pulumi provider, which allows us to interact with a Rancher instance to manage its resources. Note that actual deployment of the Rancher server itself is not typically handled by Pulumi; rather, we use Pulumi to manage resources within an already running Rancher environment.

In this program, we'll use `rancher2.AppV2` to deploy a Helm chart. This resource type represents a Helm chart deployment in Rancher, identical to `helm install` or `helm upgrade` commands.

I'll guide you through a Pulumi TypeScript program that will deploy the `tt-workflow` Helm chart on a Rancher cluster.

### The Pulumi Program
```typescript
import * as pulumi from '@pulumi/pulumi';
import * as rancher2 from '@pulumi/rancher2';

// Initialize a Pulumi program
const main = async () => {
  // Create a new Rancher2 App which deploys a Helm chart
  const ttWorkflowApp = new rancher2.AppV2('tt-workflow-chart', {
    // Specify the namespace where the app should be deployed
    namespace: 'your-namespace', // Replace with your namespace
    
    // Reference to the Kubernetes cluster to deploy to
    // You will need to provide the relevant cluster ID here
    clusterId: 'your-cluster-id', // Replace with your actual cluster ID
    
    // Details of the Helm chart to deploy
    repoName: 'your-repo-name', // Replace with the repository name where `tt-workflow` is located
    chartName: 'tt-workflow', // The name of the chart to deploy
    chartVersion: 'your-chart-version', // Replace with the version of the chart you want to deploy
    
    // Values to pass to the Helm chart, equivalent to `values.yaml` or `--set`
    // Provide the relevant values as per the Helm chart requirements
    values: `
      someKey: someValue
      nestedKey:
        nestedValue: value
    `,
  });

// Export the app name
  return {
    appName: ttWorkflowApp.metadata.apply(meta => meta.name),
  };
};

// Run the Pulumi program
main().then(outputs => {
  // When the app is deployed, this will print the name of the app
  console.log(`App Name: ${outputs.appName}`);
});

```
This program will create an instance representing the `tt-workflow` Helm chart deployment in Rancher. Be sure to replace placeholders like `your-namespace`, `your-cluster-id`, `your-repo-name`, `your-chart-version`, and the values under `values` with actual information according to your Rancher setup and `tt-workflow` Helm chart details.

The `values` is a string that should be formatted as YAML, analogous to what you would find in a Helm chart's `values.yaml` file, or what you would pass to the `helm` CLI with the `--set` flag. These values allow you to customize the deployment of the Helm chart.

The `appName` is exported as output from the Pulumi program. This might correspond to a stack output, allowing insight into the resources created by the Pulumi program.

### Next Steps
After writing and saving the program to `index.ts`, run following commands in the directory where you saved it:

1. `pulumi up` to initiate the deployment.
2. Review the plan shown by Pulumi and approve it, confirming that it will deploy the resources as expected.
3. Once applied, Pulumi will show you the output (in this case, the app name).

Remember, managing infrastructure as code with Pulumi is very powerful and allows you to version, share, and reuse your configurations easily.