Deploy the discord-bot helm chart on Google Kubernetes Engine (GKE)

Question

Pulumi · Accepted Answer

To deploy a Helm chart to Google Kubernetes Engine (GKE), we need to follow a few steps:

1. **Set up a GKE cluster**: A Kubernetes cluster acts as the host for our applications. We're going to create a GKE cluster instance.
2. **Install Helm**: Helm is a package manager for Kubernetes, and we need it to manage the deployment of our Discord bot Helm chart.
3. **Deploy the Helm chart**: Using Helm, we deploy the chart to our Kubernetes cluster.

For this task, we'll be using three main Pulumi resources from the Pulumi GCP and Kubernetes packages:
- `gcp.container.Cluster`: This resource will create our GKE cluster.
- `kubernetes.helm.v3.Chart`: This resource will manage the Helm chart deployment.
- `kubernetes.Provider`: This resource is used to interact with the created GKE cluster.

The following TypeScript program assumes that you already have Pulumi installed, and have authenticated with both Pulumi and Google Cloud SDK. The program also assumes that the required Helm chart for the Discord bot is available and properly configured.

Let's go ahead with the detailed code:

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

// Create a GKE cluster
const cluster = new gcp.container.Cluster("discord-bot-cluster", {
    initialNodeCount: 1,
    minMasterVersion: "latest",
    nodeConfig: {
        machineType: "n1-standard-1",
        oauthScopes: [
            "https://www.googleapis.com/auth/compute",
            "https://www.googleapis.com/auth/devstorage.read_only",
            "https://www.googleapis.com/auth/logging.write",
            "https://www.googleapis.com/auth/monitoring"
        ],
    },
});

// Export the Cluster name
export const clusterName = cluster.name;

// Export the Kubeconfig to access the GKE cluster.
export const kubeconfig = pulumi.
    all([cluster.name, cluster.endpoint, cluster.masterAuth]).
    apply(([name, endpoint, masterAuth]) => {
        const context = `${gcp.config.project}_${gcp.config.zone}_${name}`;
        return `apiVersion: v1
clusters:
- cluster:
    certificate-authority-data: ${masterAuth.clusterCaCertificate}
    server: https://${endpoint}
  name: ${context}
contexts:
- context:
    cluster: ${context}
    user: ${context}
  name: ${context}
current-context: ${context}
kind: Config
preferences: {}
users:
- name: ${context}
  user:
    auth-provider:
      config:
        cmd-args: config config-helper --format=json
        cmd-path: gcloud
        expiry-key: '{.credential.token_expiry}'
        token-key: '{.credential.access_token}'
      name: gcp
`;
    });

// Kubernetes provider that uses the generated kubeconfig
const k8sProvider = new k8s.Provider("gkeK8s", {
    kubeconfig: kubeconfig,
});

// Deploy the Discord bot Helm chart
const discordBotChart = new k8s.helm.v3.Chart("discord-bot", {
    chart: "discord-bot",
    version: "1.0.0",
    fetchOpts:{
        repo: "http://example.com/charts", // Replace with the actual Helm chart repository URL
    },
}, { provider: k8sProvider });

// Export the Discord bot service endpoint
export const discordBotService = discordBotChart.getResource("v1/Service", "discord-bot");

```

Let's break down what's happening in this program:

- We create a GKE cluster with a single node to start with. The `minMasterVersion: "latest"` means we want our cluster to be created with the latest stable version of Kubernetes master.
- We configure `nodeConfig` with an appropriate machine type and the scopes that we need for our GKE nodes.
- We then construct the `kubeconfig` required to interact with our GKE cluster programmatically.
- A Kubernetes provider (`k8s.Provider`) is set up with the generated `kubeconfig`. This provider will enable us to interact with the GKE cluster using Pulumi.
- Using `k8s.helm.v3.Chart`, we deploy the Discord bot Helm chart. The `repo` field in `fetchOpts` should point to the URL of the Helm repository that hosts our Discord bot chart.
- We're exporting the HTTP endpoint of the Discord bot service so we can interact with the deployed Discord bot.

Remember to replace `"http://example.com/charts"` with the actual repository URL for the Discord bot Helm chart.

This code is a full Pulumi program that can be executed with the standard Pulumi CLI commands (`pulumi up` to deploy, `pulumi destroy` to tear down). Once you run `pulumi up`, it will deploy the specified Helm chart on a GKE cluster, and you will be given a service endpoint to access your Discord bot.