Deploy the benthos helm chart on Azure Kubernetes Service (AKS)

Question

Pulumi · Accepted Answer

To deploy the Benthos helm chart on Azure Kubernetes Service (AKS), we'll walk through the following steps:

1. **Set up an AKS cluster**: We need a Kubernetes cluster to deploy our Helm chart to. We'll create one using Pulumi’s `azure-native` package.
2. **Install Helm and Tiller**: Helm is a package manager for Kubernetes, and Tiller is the server-side component Helm connects to. AKS clusters come with Helm pre-installed, but depending on the Helm version, Tiller might not be necessary.
3. **Deploy Benthos**: Once Helm is set up, we can deploy Benthos by specifying the Helm chart.

Let's write a Pulumi program in TypeScript to accomplish this. Below is the complete Pulumi program that creates an AKS cluster and deploys the Benthos Helm chart to it:

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

// Create an Azure Resource Group
const resourceGroup = new azureNative.resources.ResourceGroup("myResourceGroup");

// Create an AKS cluster
const cluster = new azureNative.containerservice.ManagedCluster("myAksCluster", {
    resourceGroupName: resourceGroup.name,
    agentPoolProfiles: [{
        count: 1,
        vmSize: "Standard_B2s",
        name: "agentpool" // Default agent pool name
    }],
    dnsPrefix: "myakscluster", // Ensure this is globally unique
    identity: {
        type: "SystemAssigned", // Use a system assigned identity for the AKS cluster
    },
    location: resourceGroup.location,
});

// Expose the kubeconfig for the AKS cluster
const creds = pulumi.all([cluster.name, resourceGroup.name]).apply(([aksName, rgName]) =>
    azureNative.containerservice.listManagedClusterUserCredentials({
        resourceGroupName: rgName,
        resourceName: aksName,
    }));

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

// Create a Pulumi Kubernetes Provider referencing our AKS cluster
const k8sProvider = new k8s.Provider("myK8sProvider", {
    kubeconfig: kubeconfig,
});

// Install the Benthos Helm chart (assuming Benthos is available in a Helm repo)
const benthosChart = new k8s.helm.v3.Chart("benthos", {
    chart: "benthos",
    version: "0.1.0", // Specify the version of the Benthos chart to deploy
    fetchOpts: {
        repo: "https://charts.your-repo.com" // Replace with the URL of the chart's repository
    },
}, { provider: k8sProvider });

// Export the AKS cluster's kubeconfig
export const kubeConfig = kubeconfig;
```

Here's a step-by-step explanation:

- **Resource Group**: We create a resource group to organize all the resources we'll be provisioning within Azure. This is standard practice for managing Azure resources.

- **AKS Cluster**: We create an AKS cluster using the `ManagedCluster` resource within the `azure-native.containerservice` module. Here, you specify the size and count of VMs in the default node pool with `vmSize` and `count`, respectively. The `dnsPrefix` is used for the Kubernetes API server URL, and it needs to be globally unique.

- **Kubernetes Config**: After the cluster is created, we obtain the `kubeconfig`, which is necessary for our Kubernetes provider to communicate with the AKS cluster.

- **Kubernetes Provider**: We instantiate a Kubernetes provider with the obtained `kubeconfig`. This provider is responsible for the deployment of Kubernetes resources.

- **Helm Chart**: We deploy the Benthos helm chart using the Pulumi Kubernetes provider. The `Chart` resource in the `k8s.helm.v3` module deploys the Benthos Helm chart to our AKS cluster. You must specify the chart's version and its repository URL.

- **Output**: We export the `kubeconfig` so that we can interact with the AKS cluster using other tools such as `kubectl`.

Note that you need to replace `https://charts.your-repo.com` with the actual repository URL where the Benthos Helm chart is located, and the `version` with the one you intend to deploy.

To run this Pulumi program:

1. Save the code to a file with a `.ts` extension, for example, `deploy-benthos.ts`.
2. Run `pulumi up` in the same directory as your `.ts` file. Pulumi will perform the deployment according to the instructions in the program.

Remember to have `npm` package `@pulumi/pulumi`, `@pulumi/azure-native`, and `@pulumi/kubernetes` installed in your project directory, and you should have already configured Pulumi with your Azure credentials.