Deploy the postgres-instance helm chart on Opensshift

Question

Pulumi · Accepted Answer

To deploy a Helm chart on an OpenShift cluster using Pulumi, you'll typically do the following:

Set up the Pulumi project and import necessary packages.
Provide cluster connection details for OpenShift.
Use the Chart resource from the Pulumi Kubernetes provider to deploy your Helm chart to the OpenShift cluster.

Below, I'll walk you through a Pulumi program written in TypeScript that deploys the postgres-instance Helm chart onto an OpenShift cluster. For simplicity, this guide assumes you have already configured your OpenShift cluster and have the necessary credentials to access it.

First, we'll need to import the @pulumi/kubernetes package which allows us to work with Kubernetes resources, including OpenShift, since OpenShift is a Kubernetes distribution.

We will use the Chart resource which represents a Helm chart. We will specify the chart name, version, and any configuration values that we might need to pass to the chart. For the postgres-instance, I'll use a placeholder for configuration values, as the actual values you'll need to provide will depend on your specific requirements and the details of the chart you are using.

Now, let's write the Pulumi program:

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

// Create a new Kubernetes Helm Chart for the Postgres instance
const postgresChart = new k8s.helm.v3.Chart('postgres-instance', {
  // The repository where the Helm chart is located
  repo: 'https://example.com/helm-charts', // Replace with actual Helm chart repository
  // The name of the chart to install
  chart: 'postgres-instance',
  // Specify the version of the Helm chart to install
  version: '1.0.0', // Replace with the actual chart version
  // Provide values to customize the chart
  values: {
    // Keys and values here will depend on the specific chart you are using
    // For PostgreSQL, you might need to set:
    // - database name
    // - credentials: username, password
    // - storage requirements
    // - network policies
    // Please refer to the chart's values.yaml file for all available options
  },
  // The namespace to deploy the chart into
  namespace: 'postgres-namespace', // Replace with the desired namespace
  // Transformations can be applied to resources upon creation. This is not needed for a simple deployment,
  // but can be useful to modify resources on-the-fly, such as appending labels or annotations.
  transformations: [
    (resource: any) => {
      // Sample modification - adding an additional label to all resources
      if (!resource.metadata.labels) {
        resource.metadata.labels = {};
      }
      resource.metadata.labels["deployedBy"] = "pulumi";
    }
  ],
  // Additional options can be provided here for Helm fetch operations like，
  // setting up SSL verification, using a specific keyring, and so on.
  fetchOpts: {
    // Example if a custom CA is required for repository access
    // caFile: '/path/to/cafile',
    // Example if Helm needs to authenticate against the repository
    // username: '<username>',
    // password: '<password>',
  },
}, {
  // Depending on the Helm Chart, we may have to acknowledge that we're
  // dealing with resources which have CRDs by setting the `skipAwait` to true.
  // This is because Pulumi normally waits for all resources to be fully ready
  // before marking the deployment as complete. CRDs don't necessarily have
  // a 'ready' status, so skipAwait can be helpful.
  skipAwait: true,
});

// To access the deployed Helm chart, we might want to export some key URLs or
// connection details. For example:
export const postgresConnectionUrl = postgresChart.getResourceProperty(
  'v1/Service', 'postgres-instance', 'status').apply(status => status.loadBalancer.ingress[0].ip);

In the above code:

@pulumi/kubernetes package is used to interact with Kubernetes resources.
Chart resource from the @pulumi/kubernetes/helm/v3 is used to represent the Helm chart you wish to deploy.
The repo property should point to the repository of your Helm chart.
chart property is the name of the chart you want to deploy.
version property specifies a specific version of the chart to use.
values are configuration parameters specific to the chart. These can be based on the values.yaml file from the Helm chart.
namespace specifies the target Namespace for where the chart should be deployed within OpenShift.
transformations allow you to programmatically modify the Helm chart resources before they are created.
fetchOpts accommodates additional options for fetching the Helm chart, such as repository credentials.
skipAwait is an option to allow Pulumi to consider resources ready without waiting for all statuses since some Custom Resource Definitions do not have a status field that Pulumi can wait on.

Please ensure you update placeholders with the actual values relevant to your environment, especially the chart repository URL, chart version, and configuration values.

To deploy this Pulumi program, you need to have Pulumi installed and configured for your OpenShift cluster, and then you simply run pulumi up to create the resources. Make sure to review the proposed changes before confirming the deployment. After deployment, you can use the exported postgresConnectionUrl to connect to your Postgres instance.

Please note that you'll need to replace the placeholders with the actual values that fit your needs, such as the actual Helm chart repository URL, the namespace you want to deploy to, and so on. Additionally, as you're deploying a PostgreSQL database, make sure to handle sensitive information like passwords carefully, potentially by using Pulumi's secret management capabilities.