Deploy the external-scaler-azure-cosmos-db helm chart on Rancher

Question

Pulumi · Accepted Answer

To deploy a Helm chart to a Kubernetes cluster managed by Rancher, you need to perform a series of steps. First, you need to have a Kubernetes cluster registered with Rancher. Once you have the cluster, you'll need to install the Rancher CLI or use the Rancher UI to deploy the Helm chart.

For this scenario, we're assuming that the Kubernetes cluster is already set up and accessible via kubectl and that you have adequate permissions to deploy Helm charts in the cluster.

We'll be using Pulumi with TypeScript to describe and manage the deployment of the external-scaler-azure-cosmos-db Helm chart on Rancher. The program below automates these tasks:

Create a Rancher Project as a logical grouping within the Rancher environment.
Define a Rancher App, which corresponds to a Helm deployment.

Here's how you might write a Pulumi program to do this:

import * as rancher2 from "@pulumi/rancher2";
import * as k8s from "@pulumi/kubernetes";

// Create a new Rancher project.
const project = new rancher2.Project("my-project", {
    // You will need to provide the cluster ID where this project belongs
    clusterId: "<CLUSTER_ID>",
    // Properties like 'description' are optional
    description: "My project for external scaler",
});

// Create a Kubernetes provider for the newly created project.
const k8sProvider = new k8s.Provider("k8s-provider", {
    kubeconfig: project.kubeconfig,
});

// Use the k8s provider to create a new Helm chart deployment.
const helmChart = new k8s.helm.v3.Chart("external-scaler-azure-cosmos-db", {
    // Most Helm charts require you to specify a 'chart' and 'version'.
    chart: "external-scaler-azure-cosmos-db",
    version: "<CHART_VERSION>", // Specify the version of the Helm chart here
    // Set the values for the Helm chart's parameters.
    values: {
        // These values would be specific to the 'external-scaler-azure-cosmos-db' chart.
        // For example (values below are hypothetical):
        // cosmosDB: {
        //     accountName: "your-cosmos-db-accountName",
        //     databaseName: "your-cosmos-db-databaseName",
        //     collectionName: "your-cosmos-db-collectionName",
        // },
    },
}, { provider: k8sProvider }); // Ensure you're using the project specific K8s provider

In this program:

We're importing the Rancher2 and Kubernetes providers from Pulumi's libraries.
A new Rancher Project resource is being created to represent the logical grouping within Rancher where our application will be deployed.
We specify the cluster ID for the Kubernetes cluster managed by Rancher.
Using the project resource, we initialize a Kubernetes provider that is configured to deploy resources into our Rancher-managed cluster.
Then, we instantiate a Helm chart resource for external-scaler-azure-cosmos-db. The chart and version parameters are specific to the Helm chart you're deploying. You would need to fill these in with the appropriate values.
We pass the Rancher Kubernetes provider to ensure that Pulumi deploys the Helm chart to the correct cluster.
The values object allows you to provide custom values to the Helm chart, configuring it for your environment. These values will be specific to the external-scaler-azure-cosmos-db chart, and you'll want to refer to the chart's documentation for the expected fields.

Before running this Pulumi code, you will need to replace placeholder values (indicated by <...>) with real values from your environment—specifically, the cluster ID and chart version you intend to use.

To apply this deployment, you would run pulumi up in the directory where this code resides. If you're new to Pulumi, you must first install the Pulumi CLI and set up your Pulumi project with pulumi new.

Remember to refer to the official documentation of the external-scaler-azure-cosmos-db Helm chart for all configurations needed to deploy it successfully in your environment.