Deploy the prometheus-monitoring-stack helm chart on Kubernetes

Question

Pulumi · Accepted Answer

In order to deploy the Prometheus monitoring stack Helm chart on Kubernetes using Pulumi, we will use the `kubernetes.helm.v3.Chart` resource from the Pulumi Kubernetes provider. This allows us to specify a Helm chart by name (within a specified repository) and to deploy it to our cluster. The Pulumi program below will deploy the Prometheus monitoring stack to a Kubernetes cluster that has already been configured in the context of your `kubectl`.

Here's a step-by-step breakdown of what we're going to do in the Pulumi TypeScript program:

1. Import necessary packages.
2. Define a new Helm chart resource using `kubernetes.helm.v3.Chart`.
3. Specify the necessary arguments like the chart name, version, and any custom values that you might need for your Prometheus stack.

Make sure you have `kubectl` configured to connect to your Kubernetes cluster and have the Pulumi CLI installed and setup.

Below is the TypeScript program for Pulumi:

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

const prometheusChart = new k8s.helm.v3.Chart('prometheus-monitoring-stack', {
    chart: 'kube-prometheus-stack',
    version: '13.13.1', // Make sure to specify the version you want to use
    fetchOpts: {
        repo: 'https://prometheus-community.github.io/helm-charts',
    },
    // If you have custom values, specify them in 'values':
    values: {
        // Custom values to configure Prometheus chart.
        // For instance, you might want to set the storage class for persistent data:
        alertmanager: {
            persistentVolume: {
                storageClass: 'standard', // Make sure this storageClass is available in your cluster
            },
        },
        prometheus: {
            persistentVolume: {
                storageClass: 'standard', // Make sure this storageClass is available in your cluster
            },
        },
        // Add other custom configurations if needed.
    },
});

// Export the chart name and version of the deployed chart
export const chartName = prometheusChart.metadata.name;
export const chartVersion = prometheusChart.metadata.version;

```

Explanation of the code:
- We initialize a new Helm chart deployment using `new k8s.helm.v3.Chart`. This class is responsible for deploying Helm charts to a Kubernetes cluster.
- The `chart` argument specifies the name of the Helm chart we're installing, which is `kube-prometheus-stack` in this case.
- The `version` is the specific version of the chart that we want to deploy. It is always recommended to pin down a version for reproducibility.
- The `fetchOpts` contains a `repo` URL where the Helm chart is located. `https://prometheus-community.github.io/helm-charts` is the repository for the Prometheus community Helm charts.
- The `values` block allows us to specify any custom values that are specific to our deployment requirements. This can include things like persistent storage options, resource limits, and other configuration options that are specific to the Prometheus Helm chart. These values will override the defaults in the Helm chart.

Once you have this Pulumi program ready, run it with the following commands:

```bash
pulumi up
```

This command will start the Pulumi deployment process, showing you a preview of what will be deployed. After reviewing the changes, you can confirm to proceed with the actual deployment.

Remember that this program assumes that your Kubernetes cluster is already configured and accessible through `kubectl`. If you need to set up a new cluster or configure access, make sure to do that before running the Pulumi program.