Deploy the cidr-allocator helm chart on Azure Kubernetes Service (AKS)

Question

Pulumi · Accepted Answer

To deploy a Helm chart to an AKS cluster using Pulumi, you need to accomplish a few high-level steps:

1. **Provision an AKS cluster**: Before you can deploy your Helm chart, you need a running Kubernetes cluster. You would use Pulumi's `azure-native` package to provision an AKS cluster.

2. **Install the Helm chart to the AKS cluster**: Once the cluster is up and running, you can deploy the `cidr-allocator` Helm chart to it. Pulumi's `kubernetes` package provides resources for working with Helm charts.

Below, I'll provide a Pulumi program written in TypeScript that goes through these steps. The program will require you to have both `@pulumi/azure-native` and `@pulumi/kubernetes` npm packages installed. You can install them using your package manager of choice before running the program.

This program also assumes that you have already configured Pulumi with your Azure credentials, which allows Pulumi to create resources in your Azure subscription.

### Detailed Pulumi Program Explanation

```typescript
import * as pulumi from "@pulumi/pulumi";
import * as azure from "@pulumi/azure-native";
import * as k8s from "@pulumi/kubernetes";

// Step 1: Provision an AKS cluster
const resourceGroupName = new azure.resources.ResourceGroup("rg", {
    resourceGroupName: "myResourceGroup",
    location: "East US", // You can choose a different region here.
});

const managedCluster = new azure.containerservice.ManagedCluster("aks-cluster", {
    resourceGroupName: resourceGroupName.name,
    location: resourceGroupName.location,
    defaultNodePool: {
        name: "default",
        nodeCount: 2, // You can choose a different node count here.
        vmSize: "Standard_DS2_v2", // Or you can select a different VM size.
    },
    dnsPrefix: "aks-cidrallocator", // Your DNS prefix for the AKS cluster.
    identity: {
        type: "SystemAssigned",
    },
});

// Step 2: Deploy the cidr-allocator Helm chart
const k8sProvider = new k8s.Provider("k8s-provider", {
    kubeconfig: managedCluster.kubeConfigRaw,
});

new k8s.helm.v3.Chart("cidr-allocator-chart", {
    repo: "myHelmRepo", // Specify the name of your Helm chart repository.
    chart: "cidr-allocator", // The name of the chart in the repository.
    version: "1.0.0", // Specify the chart version if desired.
    namespace: "default", // The namespace to deploy the chart into.
    // values: {}, // If there are any custom values you wish to supply, specify them here.
}, { provider: k8sProvider });

// Exports are how you obtain information about the resources created by Pulumi.
// Below, we export the AKS cluster name and the kubeconfig, which can be used to interface with the cluster using kubectl or other tools.
export const clusterName = managedCluster.name;
export const kubeConfig = pulumi.secret(managedCluster.kubeConfigRaw);
```

This program first creates a new resource group in Azure to hold the AKS resources, and then it provisions an AKS cluster within that resource group. In this example, a default node pool is created with two VMs of size "Standard_DS2_v2", but these options can be adjusted according to your requirements.

After the AKS cluster is provisioned, a new Pulumi Kubernetes provider is instantiated using the kubeconfig of the AKS cluster. This provider is used to instruct the Helm chart resource to deploy to the newly created AKS cluster.

I have assumed a generic Helm chart named "cidr-allocator" which you will need to replace with the actual Helm chart name and repository information. You would also provide any `values` to customize the Helm deployment to your needs.

Finally, the `exports` at the end of the program provide you with outputs after the deployment is complete. Here, the AKS cluster name and the kubeconfig are exported. The kubeconfig, being sensitive information, is wrapped in `pulumi.secret()` to tell Pulumi to encrypt it when stored.

To apply this configuration, navigate to the directory containing `index.ts` (the file containing the code above), then execute the following commands:

```bash
# Install the required npm packages
npm install @pulumi/pulumi @pulumi/azure-native @pulumi/kubernetes

# Login to your Pulumi account (if not already logged in)
pulumi login

# Select the appropriate stack (or create a new one)
pulumi stack select dev # Or your stack name

# Preview the changes that would be made
pulumi up --yes
```

These commands will trigger Pulumi to provision the AKS cluster and deploy the `cidr-allocator` Helm chart onto it.