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

Question

Pulumi · Accepted Answer

To deploy the `dbmate` helm chart on an Azure Kubernetes Service (AKS) cluster, we'll follow several steps using Pulumi and TypeScript. First, we'll need to create the AKS cluster itself, and then we'll deploy the `dbmate` helm chart to this cluster. We'll use the Azure Native provider (`azure-native`) for creating the AKS cluster and the Kubernetes provider (`kubernetes`) to deploy the helm chart.

Here are the steps we will perform in the Pulumi program:

1. Define the AKS cluster using Pulumi's `azure-native` provider, which allows us to create and manage Azure resources. We define the necessary properties for the AKS such as location, number of nodes, node size, etc.

2. Once the AKS cluster is created, we need to configure the `kubeconfig` so that Pulumi's Kubernetes provider can interact with the AKS cluster.

3. Deploy the `dbmate` helm chart to the AKS cluster using Pulumi's `kubernetes` provider. A Helm chart is a collection of pre-configured Kubernetes resources that can be deployed as a unit. The `dbmate` chart should be available in a Helm repository, and we'll reference it directly in our chart resource definition.

Let's proceed with writing the Pulumi TypeScript program:

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

// Step 1: Define the AKS cluster
const resourceGroupName = new azureNative.resources.ResourceGroup("myResourceGroup", {
    resourceGroupName: "myResourceGroup",
    location: "East US", // You can change the location to your preference
});

const k8sCluster = new azureNative.containerservice.ManagedCluster("myAKSCluster", {
    resourceGroupName: resourceGroupName.name,
    // Define the properties for the AKS cluster here
    // For example, you could specify the number of node pools, VM size, etc.
    // For the sake of this example, we are using default values for those
    agentPoolProfiles: [{
        count: 2,
        vmSize: "Standard_DS2_v2",
        mode: "System",
        name: "agentpool", // This is the default node pool
    }],
    dnsPrefix: "myakscluster-dns",
    location: resourceGroupName.location,
    kubernetesVersion: "1.20.9",
});

// Export the kubeconfig to access the AKS cluster
export const kubeconfig = pulumi.all([k8sCluster.name, resourceGroupName.name]).apply(([name, rgName]) => {
    return azureNative.containerservice.listManagedClusterUserCredentials({
        resourceGroupName: rgName,
        resourceName: name,
    }).then(creds => Buffer.from(creds.kubeconfigs[0].value, 'base64').toString());
});

// Step 2: Configure the kubernetes provider to use the kubeconfig from the AKS
const k8sProvider = new kubernetes.Provider("k8sProvider", {
    kubeconfig: kubeconfig,
});

// Step 3: Deploy the dbmate helm chart
const dbmateChart = new kubernetes.helm.v3.Chart("dbmateChart", {
    chart: "dbmate",
    version: "1.0.0", // Replace with the version of dbmate that you want to deploy
    fetchOpts:{
        repo: "https://helm.dbmate.io", // Replace with the correct repo URL for dbmate
    },
    // Define the values for the Helm chart here
    // Depending on the helm chart, you might need to specify parameters like database URLs, etc.
    values: {
        // Example value - you would need to provide your database configuration
        // databaseURL: "your-database-connection-string",
    },
}, { provider: k8sProvider });

// Export the status URL, if the helm chart provides an endpoint
export const dbmateStatusUrl = pulumi.interpolate `http://${dbmateChart.status.loadBalancer.ingress[0].hostname}/status`;
```

This program defines three major steps with Pulumi TypeScript:

1. Resource Group and AKS Cluster Creation: We establish a resource group using `azureNative.resources.ResourceGroup` and then an AKS cluster within that group with `azureNative.containerservice.ManagedCluster`. Remember to replace placeholder values with the actual values appropriate for your use case.

2. Kubeconfig Retrieval: We export the `kubeconfig` needed to interact with the AKS cluster. This config is obtained by the `azureNative.containerservice.listManagedClusterUserCredentials` function, which fetches the credentials we need.

3. Helm Chart Deployment on AKS: Finally, we deploy the `dbmate` helm chart. Be sure to replace the placeholder values with the relevant URLs and parameters for your deployment. The `kubernetes.helm.v3.Chart` class is used to apply the helm chart to the AKS cluster, with the `k8sProvider` enabling communication with the AKS.

Remember that before you run this Pulumi program, you'll need to install Pulumi CLI, set up an account, and configure Azure credentials accordingly. Once you're all set, you can execute the program with the usual Pulumi commands:

```bash
pulumi up
```

This command will prompt you to review the changes and proceed with the deployment.

Lastly, the `dbmateStatusUrl` is an optional export, depending on whether or not the `dbmate` helm chart provides an endpoint. If it does, this will give you the URL to access your `dbmate` deployment. If the chart does not provide external endpoints, you may not need this line. Adjust according to your specific helm chart's specifications and outputs.