Deploy the prometheus-openstack-exporter helm chart on Kubernetes

Question

Pulumi · Accepted Answer

To deploy the `prometheus-openstack-exporter` Helm chart on a Kubernetes cluster using Pulumi, you'll first need to set up your Pulumi programming environment and ensure you have a configured Kubernetes cluster where you can deploy resources. If you're new to Pulumi, it's a modern infrastructure as code platform that allows you to define your infrastructure using real programming languages.

The following steps outline the process:

1. **Set up Pulumi**: Install Pulumi CLI and set up your Pulumi account. Initialize a new Pulumi project if you haven't done so yet. The Pulumi documentation is a great starting point to get you set up.

2. **Configure Kubernetes**: You need a Kubernetes cluster to work with. This can be a local one like Minikube or Docker Desktop, or a managed one in the cloud such as Amazon EKS, Google GKE, or Azure AKS. You should have `kubeconfig` configured to interact with your cluster.

3. **Define the Helm Chart deployment**: Pulumi allows you to deploy Helm charts directly using the `Chart` resource from the `kubernetes` package. You'll need to know the name of the Helm chart and the repository where it's hosted. For `prometheus-openstack-exporter`, you typically need to add the repository that contains the chart and then deploy it.

For the purpose of the demonstration we'll assume that the `prometheus-openstack-exporter` is hosted at a Helm repository at `https://helm.example.com/`. You'd normally find the correct URL for the chart you're deploying in its documentation.

Below is a Pulumi program written in TypeScript that demonstrates how to deploy a Helm chart on Kubernetes:

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

const prometheusOpenstackExporterChart = new kubernetes.helm.v3.Chart("prometheus-openstack-exporter", {
    // Set the repository where the Helm chart is located.
    repo: "example",
    // Specify the name of the chart.
    chart: "prometheus-openstack-exporter",
    // Define any values to override in the chart configuration.
    values: {
        // ...Configuration values here, e.g., connection details for OpenStack
    },
    // Define the namespace to deploy the chart into, if different from the default namespace.
    namespace: "monitoring",
    // Fetch the Helm chart from the remote repository.
    fetchOpts: {
        repo: "https://helm.example.com/",
    },
});

// Export the base URL of the exporter's service, if applicable.
export const exporterServiceUrl = prometheusOpenstackExporterChart.getResourceProperty("v1/Service", "prometheus-openstack-exporter-service", "status").apply(status => status.loadBalancer.ingress[0].hostname || status.loadBalancer.ingress[0].ip);
```

Explanation of the Pulumi program:

- We import the `@pulumi/kubernetes` package which contains all the necessary components for interacting with Kubernetes clusters.
- We declare a new Helm chart resource using the `kubernetes.helm.v3.Chart` class. The name of the resource is set to `"prometheus-openstack-exporter"`.
   - `repo`: Specifies the name of the repository within the Helm chart repo that you have configured.
   - `chart`: This is the name of the chart you want to deploy.
   - `values`: These are the configurations for the chart, which you might need to modify according to your Prometheus or OpenStack setup.
   - `namespace`: This denotes the Kubernetes namespace where the chart should be deployed. Here, it's set to `"monitoring"`. If this namespace doesn't exist, you'll need to create it beforehand; otherwise, Helm will attempt to create the namespace for you.
   - `fetchOpts`: This is where you provide additional options to fetch the Helm chart, such as the URL of the Helm repository.

- The `exporterServiceUrl` is exported to provide a way to access the `prometheus-openstack-exporter` service from outside the cluster. This assumes that your service has been set up with an external LoadBalancer and that it provides an IP or hostname. You may need to adjust this based on your specific Kubernetes service configuration.

Remember to replace `"https://helm.example.com/"` and chart configurations with the actual repository URL and the values that match your environment.

After you've set up the Pulumi program, you can run it with the following commands:
```bash
pulumi up # This command creates or updates resources
```

The `pulumi up` command will prompt you to confirm the deployment after showing you a preview of the changes that will be made to your infrastructure based on your Pulumi program. If everything looks correct, confirm the deployment, and Pulumi will proceed with deploying the Helm chart to your Kubernetes cluster.