Deploy the Wordress helm chart on Kubernetes

Question

Pulumi · Accepted Answer

To deploy the WordPress Helm chart on a Kubernetes cluster using Pulumi, we need to use the `kubernetes` package to define a `Chart` resource. This resource is used to deploy applications packaged as Helm charts in a Kubernetes cluster. The Helm chart for WordPress encapsulates all the Kubernetes resources needed to run WordPress and configure them through a set of predefined values.

Below is a Pulumi program written in TypeScript that deploys the WordPress Helm chart to a Kubernetes cluster. Before running the code, you need to have a Kubernetes cluster running and configured to be the current context in your kubeconfig file, which Pulumi will use to deploy the resources.

This program will:
1. Import the necessary Kubernetes package from Pulumi.
2. Create a new Helm chart resource for WordPress, specifying the chart name, version, and any custom values you want to override the default chart values.

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

// Create a Kubernetes Namespace
const ns = new k8s.core.v1.Namespace("wp-namespace", {
    metadata: { name: "wordpress" },
});

// Deploy the WordPress Helm chart in the created Namespace
const wordpressChart = new k8s.helm.v3.Chart("wp-chart", {
    // Reference to the Namespace created above
    namespace: ns.metadata.name,
    // Name of the Helm chart for WordPress
    chart: "wordpress",
    // Specify the version of the Helm chart
    version: "12.1.12", // Use the appropriate version
    // We can specify a Helm repository source, or it will use the default Helm repo
    // repo: "bitnami",
    // Override default values by specifying custom values
    values: {
        // Example custom values (these are not the only options, consult the chart's values.yaml for more)
        service: {
            type: "ClusterIP", // You can use "LoadBalancer" for cloud environments
        },
        wordpressUsername: "admin",
        wordpressPassword: "admin", // It's advised to use secret references for sensitive information
        mariadb: {
            auth: {
                rootPassword: "root",     // Again, use secret references instead
                password: "wordpressdb", // And use secret references here too
            },
        },
    },
}, { dependsOn: ns });

export const wordpressUrl = wordpressChart.getResourceProperty("v1/Service", "wp-chart-wordpress", "status").apply(status => {
    return status.loadBalancer.ingress[0].hostname;
});
```

In the above program:
- We begin by importing the `@pulumi/kubernetes` library, which contains the necessary classes and functions to interact with Kubernetes objects.
- We create a new Kubernetes namespace called `wordpress` solely for organizational purposes, which helps us manage components related to WordPress distinct from other components in our cluster.
- Next, we declare a new Helm chart resource using `new k8s.helm.v3.Chart` and provide it with necessary parameters like the name of the chart, the chart version, and custom values. These custom values will override default chart parameters such as the WordPress admin username and password, as well as the database credentials.
- The `export` statement at the end returns the URL of the WordPress site once it is deployed. This assumes that your WordPress service is exposed using a `LoadBalancer`. If you are using a different service type or deploying on a non-cloud environment, you would access WordPress differently.
- The `dependsOn` parameter ensures that the namespace is created before the Helm chart is applied.

Please replace the placeholders for `wordpressPassword` and `mariadb.auth.rootPassword` with secure values before deploying this stack. It is also advisable not to hardcode sensitive data in your code directly, and instead, use [Pulumi's secret management](https://www.pulumi.com/docs/intro/concepts/secrets/) to keep these values secure.

To execute this code, you'll need to have Pulumi CLI installed and configured for use with your Kubernetes cluster. Once set up, run the following commands in your terminal in the same directory as your Pulumi program file:

```shell
pulumi up
```

This command will start the deployment. Pulumi will show you a preview of the actions to be performed and ask for confirmation before proceeding. After confirming, Pulumi will execute the deployment and output the URL for your WordPress instance.