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

Question

Pulumi · Accepted Answer

To deploy the GeoNode Helm chart on Azure Kubernetes Service (AKS), we need to achieve several steps which I will guide you through:

1. **Create an Azure Kubernetes Service (AKS) Cluster**: You'll start by provisioning an AKS cluster where your GeoNode application will run.

2. **Install the Helm Chart**: Once the AKS cluster is ready, you will then use Pulumi to deploy the GeoNode application using its Helm chart.

Let's break down these steps in code using Pulumi with TypeScript.

### Step 1: Create an Azure Kubernetes Service (AKS) Cluster

First, you will create an AKS cluster. Ensure you have set up the necessary Azure credentials in your Pulumi environment. Pulumi will respect any Azure configuration set through the Azure CLI. We'll be using `azure-native` resources because they are designed to work seamlessly with the native Azure cloud platform, and they provide us with a high-fidelity representation of Azure resources.

Here is the complete Pulumi program written in TypeScript to provision an AKS cluster and deploy the GeoNode application using its Helm chart:

```typescript
import * as pulumi from "@pulumi/pulumi";
import * as azure_native from "@pulumi/azure-native"; // Import the Azure Native package
import * as k8s from "@pulumi/kubernetes"; // Kubernetes package for Pulumi

// Step 1: Create an Azure Resource Group
const resourceGroup = new azure_native.resources.ResourceGroup("myResourceGroup");

// Step 2: Create an Azure Kubernetes Service (AKS) Cluster
const managedCluster = new azure_native.containerservice.ManagedCluster("myAKSCluster", {
    resourceGroupName: resourceGroup.name,
    // Basic cluster configuration, such as the version and SKU size, can be set here
    kubernetesVersion: "1.20.9", // Choose an appropriate version
    agentPoolProfiles: [{
        count: 1,
        maxPods: 110,
        mode: "System",
        osDiskSizeGB: 30,
        osType: "Linux",
        vmSize: "Standard_DS2_v2",
        name: "agentpool" // The name for the agent pool
    }],
    dnsPrefix: `${pulumi.getStack()}-kube`,
});

// Step 3: Export the kubeconfig
const creds = pulumi.all([managedCluster.name, resourceGroup.name]).apply(([clusterName, rgName]) => {
    return azure_native.containerservice.listManagedClusterUserCredentials({
        resourceGroupName: rgName,
        resourceName: clusterName,
    });
});

// Exports a kubeconfig file for the AKS cluster
const kubeconfig = creds.apply(c => Buffer.from(c.kubeconfigs[0].value, "base64").toString());

// Step 4: Use the Pulumi Kubernetes provider to connect to the AKS cluster
const k8sProvider = new k8s.Provider("k8sProvider", {
    kubeconfig: kubeconfig,
});

// Step 5: Deploy the GeoNode Helm chart into our AKS cluster
const geonodeChart = new k8s.helm.v3.Chart("geonode", {
    chart: "geonode",
    // The repository where the Helm chart is located
    fetchOpts: {
        repo: "https://helm.geonode.org/", // Replace with the correct URL of the Helm repository for GeoNode
    },
    // If the Helm chart requires value override, they can be specified in the 'values' property
    values: {
        // Example value override: set the number of replicas for the GeoNode deployment
        replicaCount: 1,
    },
}, { provider: k8sProvider });

// Export the AKS cluster name and kubeconfig
export const clusterName = managedCluster.name;
export const kubeConfig = pulumi.secret(kubeconfig);

```

### Explanation:

- **Resource Group**: The first step is to create a Resource Group, which is a logical container where the resources relating to the AKS cluster will reside.

- **AKS Cluster**: We instantiate a ManagedCluster resource representing our AKS cluster. We specify basic configuration details, like the Kubernetes version and the size of the virtual machines in the node pool.

- **Kubernetes Credentials**: We then get the credentials needed to interact with our AKS cluster programmatically.

- **Kubeconfig**: We export the kubeconfig which you will use to configure kubectl locally or in automation pipelines.

- **Kubernetes Provider**: We create a Pulumi Kubernetes provider, which uses the exported kubeconfig. This provider will be used to interact with the AKS cluster.

- **Helm Chart**: Finally, we deploy the GeoNode Helm chart into the cluster. We instantiate a Chart resource from the `@pulumi/kubernetes` package, indicating the Helm Chart we wish to deploy (`geonode`) and the repository where it is found.

### How to Run:
- Ensure you have installed Pulumi and configured Azure access.
- Place the code into a file named `index.ts`.
- Run `pulumi up` to preview and deploy the changes.

Remember to check the Helm repository URL of GeoNode and ensure all necessary parameters for the chart are correctly set in the `values` object. If GeoNode requires additional configuration or sensitive data (like passwords), you should handle those using Pulumi's secret management.

After the deployment, pulumi will output the name of the cluster and the kubeconfig, which you can use to interact with your AKS cluster and manage applications.