Deploy the flaskapp helm chart on Digital Ocean Kubernetes Service

Question

Pulumi · Accepted Answer

To deploy a Helm chart on the Digital Ocean Kubernetes Service using Pulumi, we'll start by creating a new Kubernetes cluster on Digital Ocean. Once our cluster is set up, we'll use the Helm chart resource to deploy the Flask application.

Here is how you can achieve this step-by-step in Pulumi with TypeScript:

1. **Set up a new Digital Ocean Kubernetes cluster**: Using the `digitalocean.KubernetesCluster` resource, we'll define the specifications for our new Kubernetes cluster, including the region, version, and node pool configuration.
2. **Deploy the Helm chart**: With the Kubernetes cluster running, we'll use the `kubernetes.helm.v3.Chart` resource to deploy the Helm chart. We'll specify the chart name (in this case, `flaskapp`), and if it's from a public Helm repo, we'll also specify the repo URL.

Here's the program written in TypeScript to perform the above tasks:

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

// Create a Digital Ocean Kubernetes cluster
const cluster = new digitalocean.KubernetesCluster("do-cluster", {
    // Specify the region where the cluster will be created
    region: "nyc3",
    // Specify the version of Kubernetes to use
    version: "latest",
    // Configuration for the node pool
    nodePool: {
        name: "default",
        size: "s-2vcpu-4gb", // This is the size of the droplet (VM) used for the nodes
        nodeCount: 2, // Number of nodes in the node pool
    },
    // Additional options can be provided, such as tags or maintenance policy
});

// Use the just-created cluster's kubeconfig to interact with it
const k8sProvider = new kubernetes.Provider("k8s", {
    kubeconfig: cluster.kubeConfigs[0].rawConfig,
});

// Deploy the FlaskApp helm chart onto the Digital Ocean Kubernetes cluster
const flaskAppHelmChart = new kubernetes.helm.v3.Chart("flaskapp-helm-chart", {
    chart: "flaskapp",
    // If the Helm chart is stored in a public repository, provide the `repo` attribute
    // repo: "https://example.com/helm-charts",
    // Values from the values.yaml file can be provided here
    values: {
        //... Your Flask app specific values
    },
}, { provider: k8sProvider });

// Export the cluster's kubeconfig and the Flask app service endpoint
export const kubeconfig = cluster.kubeConfigs[0].rawConfig;
export const endpoint = flaskAppHelmChart.getResourceProperty("v1/Service", "flaskapp", "status").apply(status => status.loadBalancer.ingress[0].ip);
```

In the provided code:

- We first create an instance of the `KubernetesCluster` which initiates the creation of the cluster on Digital Ocean with the specified configuration.
- We then create a `Provider` for Kubernetes which allows Pulumi to perform actions on the Kubernetes cluster. The `kubeconfig` is used by Pulumi to authenticate against and manage the cluster.
- Finally, we define a `Chart` resource with the `flaskapp` chart. If this chart is part of an existing public or private Helm repository, you'll need to provide the URL (commented as `repo`).

This Pulumi program will set up the Kubernetes cluster, configure it for use, and then deploy the Flask application through the specified Helm chart. After running `pulumi up`, the resources will be provisioned and deployed on Digital Ocean, and you'll get the cluster's kubeconfig and the IP address of the Flask app service as outputs.

To apply this configuration, you would run it with the Pulumi CLI, after initializing a new Pulumi project and setting up your Digital Ocean provider configuration. Please replace the `flaskapp` and any value placeholders with the actual name of your chart and appropriate configurations for your application.