Deploy the flaskapp helm chart on Rancher

Question

Pulumi · Accepted Answer

To deploy a `flaskapp` Helm chart on a Rancher-managed Kubernetes cluster, we'll follow these steps using Pulumi and the `rancher2` package:

1. Set up Rancher with necessary configurations.
2. Deploy a Kubernetes cluster to be managed by Rancher. For simplicity, we'll assume you have an existing cluster registered with Rancher.
3. Deploy the Helm chart to the Rancher-managed cluster.

In the following Pulumi program, I will focus on steps 2 and 3, assuming you already have a Rancher server set up and accessible. We will use the `rancher2` Pulumi provider to interact with Rancher, and the `kubernetes` provider to deploy the Helm chart. Make sure to have Pulumi and the `rancher2` provider configured with appropriate credentials.

```typescript
import * as rancher2 from "@pulumi/rancher2";
import * as k8s from "@pulumi/kubernetes";

// Step 2: Interact with your existing Rancher-managed Kubernetes cluster.
// Here we're assuming that the cluster already exists and is registered with Rancher.
// You should replace "existing-cluster-id" with the actual ID of your Rancher cluster.
const cluster = new rancher2.Cluster("existing-cluster", {
    clusterId: "existing-cluster-id",
});

// Step 3: Deploy the flaskapp Helm Chart to the Rancher-managed cluster.
// First, we need to set up the Kubernetes provider to interact with the Rancher Kubernetes cluster.
const k8sProvider = new k8s.Provider("k8s-provider", {
    kubeconfig: cluster.kubeConfigRaw,
});

// Now let's define the Helm chart deployment. We assume there's a Helm repository that hosts the flaskapp chart.
const flaskAppChart = new k8s.helm.v3.Chart("flaskapp-chart", {
    chart: "flaskapp",
    version: "1.0.0", // Replace with the actual version of the Flask app helm chart.
    fetchOpts:{
        repo: "http://your-helm-chart-repository/", // Replace with the actual URL of your helm chart repository.
    },
}, { provider: k8sProvider });

// Export the URL for the deployed application. This will likely need to be customized based on your chart.
export const applicationUrl = k8sProvider.endpoint;
```

### Explanation:

- **Rancher Cluster**: We create a reference to an existing Rancher-managed cluster using its ID. The `Cluster` Pulumi resource allows you to manage life cycle of a Kubernetes cluster within Rancher. In this case, we are just using it to obtain kubeconfig information.
  
- **Kubernetes Provider**: We use the obtained `kubeConfigRaw` from the Rancher cluster resource to configure the Kubernetes provider. This allows Pulumi to perform actions against the Rancher-managed cluster.
  
- **Flaskapp Helm Chart**: We define a Pulumi Helm Chart resource that represents the Flask application. With Pulumi's Helm support, you can deploy Helm charts in a similar way to how you would using the helm CLI. We assume that your Flask app is packaged as a Helm chart and is available in a chart repository.

- **Export**: At the end, we provide an export statement that would give us the URL to access the deployed Flask application once it's up and running. This value is dependent on how your Helm chart exposes the application (e.g., via a LoadBalancer service or an Ingress controller). You would customize the export according to your chart's specifics.

To use this Pulumi program, you'll need to replace placeholder values (like `"existing-cluster-id"`, the flaskapp chart version, and the Helm repo URL) with actual values that correspond to your setup.

Ensure that you have the appropriate Pulumi stack selected and that your Kubernetes cluster is properly connected to your Rancher management server before executing `pulumi up` to deploy this program.