Deploy the mutating-webhook helm chart on Azure Kubernetes Service (AKS)

Question

Pulumi · Accepted Answer

To deploy the mutating-webhook Helm chart on Azure Kubernetes Service (AKS), you will need to perform some key steps:

1. **Set up an AKS cluster**: An AKS cluster is required as the foundational environment for deploying any Kubernetes resources, including Helm charts.
   
2. **Install and configure Helm**: Helm is a package manager for Kubernetes that simplifies deploying and managing applications.

3. **Deploy the mutating-webhook Helm chart**: With Helm installed and your AKS cluster running, you can then proceed to deploy the Helm chart.

Here's a program in TypeScript using Pulumi SDKs that performs these steps:

### Detailed Explanation Before the Program:

Below you will find a Pulumi program written in TypeScript that executes the above steps. The program starts by importing the necessary Pulumi libraries for Azure and Kubernetes. It then proceeds to create an AKS cluster using `azure-native`, specifically the `ManagedCluster` class, which represents an AKS cluster in Azure. Once the cluster is created, we configure Pulumi to use the resulting kubeconfig to deploy resources to this cluster. Lastly, we use the `Chart` resource from the `@pulumi/kubernetes` package to deploy the mutating-webhook Helm chart onto the AKS cluster.

### The Program:

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

// Step 1: Create an AKS cluster
const resourceGroup = new azure_native.resources.ResourceGroup("resourceGroup");

const aksCluster = new azure_native.containerservice.ManagedCluster("aksCluster", {
    resourceGroupName: resourceGroup.name,
    agentPoolProfiles: [{
        count: 1,
        vmSize: "Standard_DS2_v2",
        mode: "System",
        name: "agentpool",
    }],
    dnsPrefix: "pulumi-aks-k8s",
    enableRbac: true,
});

// Step 2: Use the resulting kubeconfig from the cluster creation to set up the Kubernetes provider
const credentials = pulumi.all([resourceGroup.name, aksCluster.name]).apply(([rgName, clusterName]) =>
    azure_native.containerservice.listManagedClusterUserCredentials({
        resourceGroupName: rgName,
        resourceName: clusterName,
    }));

const kubeconfig = credentials.kubeconfigs[0].value.apply((enc) => Buffer.from(enc, "base64").toString());

const k8sProvider = new k8s.Provider("k8sProvider", {
    kubeconfig: kubeconfig,
});

// Step 3: Deploy the mutating-webhook Helm chart using the Kubernetes provider
const mutatingWebhookChart = new k8s.helm.v3.Chart("mutatingWebhookChart", {
    chart: "mutating-webhook",
    version: "1.0.0", // Replace with the exact chart version
    // Add any values here that you want to override the default Helm chart values
    values: {
        // Provide custom values for the Helm chart if necessary
    },
}, { provider: k8sProvider });

// Export the cluster's kubeconfig.
export const kubeConfigOut = kubeconfig;
```

### Detailed Explanation After the Program:

- **Resource Group**: We create a resource group named `resourceGroup`, which will contain our AKS cluster and related resources.

- **AKS Cluster**: The `ManagedCluster` resource named `aksCluster` represents the AKS cluster. We have specified that our cluster will have one node, with a specific VM size. The `dnsPrefix` is needed for the FQDN of the cluster, and `enableRbac` is set to true for role-based access control.

- **Kubernetes Provider**: We create an instance of the Pulumi Kubernetes Provider, `k8sProvider`, which is required to specify which Kubernetes cluster to deploy resources to. We use the credentials from our AKS cluster to populate the `kubeconfig` of this provider.

- **Helm Chart**: To deploy the mutating-webhook Helm chart, we create a `Chart` resource named `mutatingWebhookChart`, specifying the name of the chart and the version. If the Helm chart expects any specific values, these can be provided in the `values` property.

- **Outputs**: The `kubeConfigOut` export exposes the `kubeconfig` string that can be used with `kubectl` or other Kubernetes tools to interact with the AKS cluster outside of Pulumi.

By running this Pulumi program, you would be setting up an Azure Kubernetes Service (AKS) cluster and deploying the mutating-webhook Helm chart onto it. The export at the end of this program provides the `kubeconfig` information necessary for you to interact with your Kubernetes cluster using standard tooling such as `kubectl`.

Please note that the `version` of `mutating-webhook` in the `Chart` resource is set as "1.0.0" as an example. You should replace this with the actual version of the Helm chart you wish to use. Additionally, any necessary Helm values are to be provided in the `values` field within the `Chart` resource. If your scenario requires any further customization or any specific `values` to be set for the `mutating-webhook` Helm chart, you would include them there accordingly.