Deploy the tyk-stack helm chart on Azure Kubernetes Service (AKS)

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Pulumi · Accepted Answer

To deploy the Tyk Stack Helm chart on Azure Kubernetes Service (AKS), you'll need to perform a series of steps. This will involve creating an AKS cluster on Azure, preparing the Kubernetes environment, and then using Pulumi to deploy the Helm chart.

The key resources we'll be using are:

1. `KubernetesCluster`: This resource will be used to create and configure the AKS cluster within your Azure subscription.
2. `helm.v3.Chart`: This component is a part of Pulumi's `@pulumi/kubernetes` package which allows you to deploy Helm charts into a Kubernetes cluster.

Here's a step-by-step Pulumi program written in TypeScript that will create an AKS cluster and deploy the Tyk Stack Helm chart:

```typescript
import * as pulumi from "@pulumi/pulumi";
import * as azure from "@pulumi/azure";
import * as k8s from "@pulumi/kubernetes";
import * as random from "@pulumi/random";

// Create an Azure Resource Group
const resourceGroup = new azure.core.ResourceGroup("tykResourceGroup");

// Create an AKS cluster
const aksCluster = new azure.containerservice.KubernetesCluster("tykK8sCluster", {
    resourceGroupName: resourceGroup.name,
    dnsPrefix: `${pulumi.getStack()}-k8s`,
    defaultNodePool: {
        name: "default",
        nodeCount: 2,
        vmSize: "Standard_DS2_v2",
    },
    identity: {
        type: "SystemAssigned",
    },
});

// Export the AKS cluster kubeconfig
export const kubeconfig = aksCluster.kubeConfigRaw;

// Create a provider for the AKS cluster
const k8sProvider = new k8s.Provider("k8sProvider", {
    kubeconfig: kubeconfig,
});

// Create a namespace for Tyk
const tykNamespace = new k8s.core.v1.Namespace("tyk-namespace", {
    metadata: { name: "tyk" },
}, { provider: k8sProvider });

// Now we deploy the Tyk Stack Helm chart within the AKS cluster
const tykHelmChart = new k8s.helm.v3.Chart("tyk-stack", {
    chart: "tyk-pro", // Replace with "tyk-headless" if you wish to use Tyk's headless gateway
    version: "0.9.0", // This should be the version you wish to deploy; check Helm repository for the latest
    namespace: tykNamespace.metadata.name,
    fetchOpts: {
        repo: "https://helm.tyk.io/public/helm/charts/", // Tyk's Helm repository
    },
    values: {
        // Set the required values for Tyk Pro. These might include sensitive information such as
        // passwords, secrets, license keys, and so forth. Store these securely.
    },
}, { provider: k8sProvider });

// Export the Tyk Gateway service endpoint
export const tykGatewayEndpoint = tykHelmChart.getResourceProperty("v1/Service", "tyk-gateway", "status").apply(s => `http://${s.loadBalancer.ingress[0].ip}`);
```

Let me explain the code above:

- **Resource Group Creation**: We start by creating an Azure resource group to logically group the AKS resources.
- **AKS Cluster Creation**: The `KubernetesCluster` resource from the `@pulumi/azure` package is used to create an AKS cluster. The DNS prefix, node pool configuration, and identity type are set for the cluster.
- **KubeConfig Export**: We export the raw Kubernetes config which is necessary to communicate with the AKS cluster.
- **Kubernetes Provider Setup**: We instantiate a Pulumi Kubernetes provider configured with the AKS cluster's kubeconfig. This allows Pulumi to deploy resources to the AKS cluster.
- **Tyk Namespace Creation**: Before deploying the Helm chart, we create a separate Kubernetes namespace named `tyk`.
- **Tyk Helm Chart Deployment**: Using the `helm.v3.Chart` resource, we deploy the Tyk Stack Helm chart into the designated namespace. We specify the chart name, version, repository, and any necessary values. Note that the values should include authentication and configuration settings according to the Tyk chart's requirements.
- **Service Endpoint Export**: Lastly, we export the endpoint of the Tyk Gateway, which will be the external IP provided by AKS once the load balancer is set up by the Helm chart.

You'll need to replace the placeholder values with actual configurations suitable for your setup, particularly under the `values` property of the `tykHelmChart`. This is where you'd specify Tyk-specific configurations.

To run this program, you will need to have Pulumi CLI installed and set up with appropriate access to your Azure account. Save the code into a file named `index.ts`, and then use the following Pulumi CLI commands:

```bash
pulumi stack init dev  # Initializes a new stack for your project
pulumi up              # Deploys the resources defined in the program
```

Remember to review the preview provided by `pulumi up` before confirming the deployment, to ensure that everything is configured as expected. After the deployment is successfully completed, Pulumi will display the output variables, including the Kubernetes cluster's kubeconfig and the Tyk Gateway endpoint.