Deploy the twitter-app helm chart on Azure Kubernetes Service (AKS)

Question

Pulumi · Accepted Answer

Deploying a Helm chart on Azure Kubernetes Service (AKS) involves several steps. First, you'll need to create an AKS cluster where your Helm chart will be deployed. Once the cluster is ready, you can configure Pulumi to use Kubernetes and Helm providers to deploy your `twitter-app` chart to the newly created AKS cluster.

Below is a TypeScript program using Pulumi to automate this process. The program will perform the following actions:

1. Create an AKS cluster using the `azure-native` provider.
2. Once the cluster is created, obtain the Kubeconfig to interact with the cluster.
3. Configure the Kubernetes provider with the obtained Kubeconfig.
4. Deploy the `twitter-app` Helm chart to the AKS cluster using the `kubernetes` provider.

Here's how this can be done in Pulumi:

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

const config = new pulumi.Config();

// Create an AKS cluster.
const resourceGroupName = config.require("resourceGroupName");
const location = config.require("location");
const clusterName = "twitterAppCluster";

const resourceGroup = new azureNative.resources.ResourceGroup("resourceGroup", {
    resourceGroupName: resourceGroupName,
    location: location,
});

const cluster = new azureNative.containerservice.ManagedCluster("cluster", {
    resourceGroupName: resourceGroup.name,
    resourceName: clusterName,
    location: resourceGroup.location,
    agentPoolProfiles: [{
        count: 2,
        maxPods: 110,
        mode: "System",
        name: "agentpool",
        osType: "Linux",
        vmSize: "Standard_DS2_v2",
    }],
    dnsPrefix: clusterName,
    enableRBAC: true,
    kubernetesVersion: "1.19.11",
});

const creds = pulumi.all([cluster.name, resourceGroup.name]).apply(([clusterName, rgName]) =>
    azureNative.containerservice.listManagedClusterUserCredentials({
        resourceGroupName: rgName,
        resourceName: clusterName,
    }));

const kubeconfig = creds.apply(creds => Buffer.from(creds.kubeconfigs[0].value, 'base64').toString());

// Create a Kubernetes provider instance using the kubeconfig from AKS.
const k8sProvider = new k8s.Provider("k8sProvider", {
    kubeconfig: kubeconfig,
});

// Deploy the Helm chart using the Kubernetes provider.
const twitterAppHelmChart = new k8s.helm.v3.Chart("twitterApp", {
    chart: "twitter-app",
    // Replace 'repo' with the URL of the chart repository
    fetchOpts: { repo: "https://charts.example.com/" },
    // If 'twitter-app' requires any values, they can be supplied here.
    values: { /* ... */ },
}, { provider: k8sProvider });

// Export the kubeconfig to access the AKS cluster.
export const kubeConfigOutput = pulumi.secret(kubeconfig);
// Optionally export other outputs like the public IP of the load balancer, if 'twitter-app' exposes any services
// export const twitterAppPublicIP = ...;
```

In this program, we set up an AKS cluster with a system node pool. The `listManagedClusterUserCredentials` function is used to fetch the necessary credentials to interact with the AKS cluster, and we decode the kubeconfig which is a base64 encoded value.

The `k8s.Provider` is instantiated with the obtained kubeconfig which will allow Pulumi to deploy Kubernetes resources to our AKS cluster. The `k8s.helm.v3.Chart` resource represents the Helm chart we want to deploy, in this case, the `twitter-app`.

If your Helm chart requires additional configuration values, they should be specified in the `values` object.

Remember to replace the placeholder values for `resourceGroupName`, `location`, and the chart repository in the `fetchOpts` object with the actual values you intend to use.

Additional outputs, such as the public IP of any service exposed by the Helm chart, can be exported if needed.

**Note:** Before running this program, ensure you have configured Pulumi with the necessary Azure credentials, and that the Helm chart `twitter-app` exists in the repository you specified. Also, you might need to adjust the `kubernetesVersion` and `vmSize` according to your requirements.