Deploy the http-headers helm chart on Azure Kubernetes Service (AKS)

Question

Pulumi · Accepted Answer

To deploy an `http-headers` Helm chart on Azure Kubernetes Service (AKS), we will first need to provision an AKS cluster, and then deploy the Helm chart to this cluster.

### Provisioning an AKS Cluster

To begin, we will provision an AKS cluster using the `azure-native` provider in Pulumi. This is done by creating an instance of `ManagedCluster` using the `azure-native.containerservice` module. The cluster will have a specified number of nodes (agent pool) and a version of Kubernetes assigned.

### Deploying the Helm Chart

Once we have our AKS cluster in place, we will use the `kubernetes.helm.v3.Chart` resource from the `kubernetes` package to deploy the `http-headers` Helm chart onto our AKS cluster. The `Chart` resource abstracts Helm chart deployments and allows you to deploy any Helm chart from a local path, a public or private chart repository, or a direct URL to the chart.

Below you will find a TypeScript program that creates an AKS cluster and deploys a Helm chart to it. Please ensure you have your Azure credentials configured for Pulumi; if not, use the Azure CLI to sign in with `az login` before running the Pulumi program.

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

// Define name and resource group for the AKS cluster
const name = "myakscluster";
const resourceGroupName = "myResourceGroup";

// Create an Azure resource group
const resourceGroup = new azure_native.resources.ResourceGroup(resourceGroupName);

// Provision an AKS cluster
const aksCluster = new azure_native.containerservice.ManagedCluster(name, {
    // Use the resource group name from the previously created resource group
    resourceGroupName: resourceGroup.name,
    agentPoolProfiles: [{
        count: 3,
        maxPods: 110,
        mode: "System",
        name: "agentpool",
        osType: "Linux",
        type: "VirtualMachineScaleSets",
        vmSize: "Standard_DS2_v2",
    }],
    dnsPrefix: `${name}-kube`,
    enableRBAC: true,
    kubernetesVersion: "1.21.9",
    location: resourceGroup.location,
});

// Export the AKS KubeConfig
export const kubeConfig = aksCluster.kubeConfig;

// Create a k8s provider using the above AKS KubeConfig
const k8sProvider = new k8s.Provider(name, {
    kubeconfig: kubeConfig,
});

// Deploy the http-headers Helm chart to the AKS cluster
const httpHeadersChart = new k8s.helm.v3.Chart("http-headers", {
    chart: "http-headers", // Should be replaced with the actual chart name or path
    version: "0.1.0", // Replace with the desired chart version
    // Additional Helm chart values can be specified if needed,
    // such as configuration parameters.
}, { provider: k8sProvider });

// Export the deployed service endpoint
export const httpHeadersService = httpHeadersChart.getResource("v1/Service", "http-headers", "http-headers-service");
```

### Explanation

1. We first create a new Azure resource group with `azure_native.resources.ResourceGroup` to organize all our AKS-related resources.
   
2. The `ManagedCluster` resource represents the AKS cluster. We define the `agentPoolProfiles` that specify the size and number of nodes in the cluster. The `enableRBAC` property enables Role-Based Access Control on the AKS cluster, a best practice for securing Kubernetes clusters.

3. We export `kubeConfig` which is the KubeConfig of the created AKS cluster allowing you to interact with your cluster using `kubectl` or other Kubernetes management tools.

4. We instantiate the Kubernetes provider for Pulumi to indicate that we want to interact with the AKS cluster we have created. We pass the `kubeConfig` exported from the AKS cluster as an argument, which contains the necessary information to communicate with the Kubernetes API server.

5. With the Kubernetes provider configured, we can now deploy the `http-headers` Helm chart. We specify the name of the chart and the version we want to deploy. Comment placeholders suggest where additional configuration can be passed if your Helm chart requires it.

6. We export the endpoint of the service deployed by the Helm chart. This only works if the Helm chart contains a Kubernetes service named `http-headers-service`. If the service has a different name, adjust the `getResource` call accordingly.

Once this Pulumi program is executed, it will provision a new AKS cluster and deploy the specified Helm chart to it. Ensure that you specify the correct Helm chart name and version, and that your chart is accessible by Pulumi.