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

Question

Pulumi · Accepted Answer

Deploying a Helm chart on AKS involves several high-level steps, which will be codified into a Pulumi program written in TypeScript. Below, I will outline the process and demonstrate how to write such a program. The explanation will include creating an Azure Kubernetes Service cluster, installing the necessary configurations for Helm, and finally deploying the `prometheus-webhook-dingtalk` Helm chart.

### Resources Used:

1. **AKS Cluster**: We will create an AKS cluster using the `azure-native.hybridcontainerservice.ProvisionedCluster` resource. This resource allows us to provision a fully managed Kubernetes cluster on Azure.

2. **Helm Chart**: For deploying Helm charts, we use the `kubernetes.helm.sh/v3.Chart` resource. It's a high-level component provided by Pulumi's Kubernetes provider that encapsulates the Helm CLI's capabilities to deploy charts.

### Steps:

1. **Setting up the AKS Cluster**: You will need to define an AKS cluster with specific properties, such as the location, number of nodes, and VM sizes for the nodes.

2. **Configuration for Helm**: After the AKS cluster is up, you would configure kubectl to interact with your newly created cluster and set up Helm to deploy charts to it.

3. **Deploying Helm Chart**: Finally, you will deploy the `prometheus-webhook-dingtalk` using the Helm chart, specifying the chart name, repository, and any custom values required for your configuration.

### Explanation of the Program:

The given program first declares the use of required Pulumi packages and sets up configuration values such as the location where the cluster will be provisioned. The main part of the program is divided into two parts: provisioning the AKS cluster and then deploying the Helm chart on the provisioned cluster.

Let's take a look at the Pulumi TypeScript program:

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

// Step 1: Creating the AKS cluster
// Define the Azure region where the cluster should be created
const location = azureNative.core.Location.WestUS2;

// Create a resource group for the AKS cluster
const resourceGroup = new azureNative.resources.ResourceGroup("myResourceGroup", { location });

// Create an AKS service principal for the cluster
const adApp = new azuread.Application("my-aks-sp");
const adSp = new azuread.ServicePrincipal("my-aks-sp", { applicationId: adApp.applicationId });
const adSpPassword = new azuread.ServicePrincipalPassword("my-aks-sp-password", {
    servicePrincipalId: adSp.id,
    endDate: "2099-01-01T00:00:00Z",
});

// Create the AKS cluster
const cluster = new azureNative.containerservice.ManagedCluster("myCluster", {
    resourceGroupName: resourceGroup.name,
    agentPoolProfiles: [{
        count: 2,
        maxPods: 110,
        mode: "System",
        name: "agentpool",
        osType: "Linux",
        vmSize: "Standard_DS2_v2",
        type: "VirtualMachineScaleSets",
    }],
    dnsPrefix: "myaksdns",
    enableRbac: true,
    kubernetesVersion: "1.18.14",
    linuxProfile: {
        adminUsername: "adminuser",
        ssh: {
            publicKeys: [{ keyData: "ssh-rsa AAA..." }],
        },
    },
    servicePrincipalProfile: {
        clientId: adApp.applicationId,
        secret: adSpPassword.value,
    },
    location,
});

// Export the kubeconfig
export const kubeconfig = pulumi.
    all([cluster.name, resourceGroup.name]).
    apply(([clusterName, rgName]) => {
        return azure.containerservice.getKubeConfig({
            name: clusterName,
            resourceGroupName: rgName,
        });
    });

// Step 2: Deploy the prometheus-webhook-dingtalk Helm chart
// Add the stable Helm chart repo
const helmRepo = new k8s.helm.v3.Repository("stableRepo", {
    url: "https://charts.helm.sh/stable",
});

// Deploy the Helm chart
const dingtalkChart = new k8s.helm.v3.Chart("prometheus-webhook-dingtalk", {
    repo: "stable",
    chart: "prometheus-webhook-dingtalk",
    version: "1.0.0", // Use the appropriate chart version
    // This fetches the generated kubeconfig to be used for Helm operations
    // After the AKS is provisioned, this kubeconfig is used to interact with it
    fetchOpts: {
        kubeconfig: kubeconfig.apply(JSON.stringify),
    },
    // If there are any specific configuration options you need, they would be placed here
    values: {},
}, { provider: new k8s.Provider("k8sProvider", { kubeconfig }) });

// Export the endpoint to access prometheus-webhook-dingtalk
export const dingtalkEndpoint = dingtalkChart.getResourceProperty("v1/Service", "prometheus-webhook-dingtalk", "status").apply(status => status.loadBalancer.ingress[0].ip);
```

In this program:

- We start by importing the necessary Pulumi packages for Azure, Kubernetes, and configuration management.
- We set up an AKS cluster using a resource group and service principal. Note that the SSH key data is a placeholder (`"ssh-rsa AAA..."`) and should be replaced with your actual public SSH key.
- Once the cluster is set up, we export the `kubeconfig` which allows us to run `kubectl` commands against our cluster and perform actions like deploying applications.
- We then define a Helm chart from a repository and deploy it to our cluster using the `Chart` resource. We specify the repository URL, the chart name, and the chart version. The `values` object can be populated with configuration specific to the `prometheus-webhook-dingtalk` chart.
- Finally, we export the service endpoint so you can access the `prometheus-webhook-dingtalk` service once it's deployed.

This program is a complete and functional example of how to deploy a Helm chart to an AKS cluster using Pulumi. Be sure to replace placeholders and configuration values with those that match your specific requirements.