Deploy the mapserver helm chart on Opensshift

Question

Pulumi · Accepted Answer

To deploy the MapServer Helm chart to an OpenShift cluster, we will use Pulumi's Kubernetes provider. Specifically, we'll utilize the `Chart` resource from the `kubernetes` package, which allows us to deploy Helm charts. The `Chart` resource encapsulates a whole set of Kubernetes resources (as defined by the Helm chart) as a single Pulumi resource.

For this task, you would typically need:

1. An existing OpenShift cluster where you have administrative access.
2. The `kubeconfig` file that allows you to connect to your OpenShift cluster.
3. Helm chart details for MapServer, such as repository URL and chart name.

Assuming you have your OpenShift cluster ready and `kubeconfig` set up correctly, you can use the following Pulumi program written in TypeScript to deploy the MapServer Helm chart:

### Detailed Explanation

First, we need to create a new Pulumi program and import the necessary modules. We will use the `@pulumi/kubernetes` module to interact with the OpenShift cluster.

The `Chart` resource will require us to specify the `repo` and `chart` properties. `repo` is the Helm repository that hosts the MapServer chart, and `chart` is the name of the MapServer chart within that repository. If there are custom configurations or overrides you would like to specify, you can provide them through the `values` property as an object.

Here is an example of how we can define a `Chart` resource in Pulumi:

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

const mapserverChart = new k8s.helm.v3.Chart('mapserver', {
    // Replace with the actual repository URL and chart name for MapServer
    repo: 'mapserver-repo-url',
    chart: 'mapserver-chart-name',
    // Add any configuration overrides you may need here
    values: {
        // For example, if you need to specify a service type for MapServer
        service: {
            type: 'LoadBalancer'
        }
    },
}, { provider: openshiftProvider });

export const mapserverUrl = mapserverChart.getResource('v1/Service', 'mapserver').status.loadBalancer.ingress[0].hostname;
```

The `openshiftProvider` is an instance of a Pulumi provider that has been configured to communicate with your OpenShift cluster. It needs to be created and passed when the chart is declared if you're working in a Pulumi program where there are multiple providers or if you explicitly need to manage the provider instance. For typical scenarios, specifying the provider might not be necessary, as Pulumi will use the default provider based on your `kubeconfig`.

After instantiating your `Chart` resource, you can export any outputs you need. In this case, we've exported `mapserverUrl`, which attempts to retrieve the hostname where MapServer will be accessible once it's deployed. Keep in mind that accessing specific properties of resources created by Helm charts may differ based on the chart's implementation, so you should reference the specific Helm chart documentation for detail.

In a real-world scenario, you would replace `'mapserver-repo-url'` and `'mapserver-chart-name'` with the actual repository URL and chart name of MapServer.

### Pulumi Program

Below is a complete program that would establish a MapServer Helm chart in an OpenShift cluster:

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

// Create a provider for the existing OpenShift cluster.
const openshiftProvider = new k8s.Provider('openshift', {
    kubeconfig: process.env.KUBECONFIG, // Assumes your KUBECONFIG is set in the environment
});

// Deploy the MapServer helm chart.
const mapserverChart = new k8s.helm.v3.Chart('mapserver', {
    chart: 'mapserver', // The chart name for MapServer within the Helm repository
    version: 'x.y.z', // Specify the Chart version that you want to use
    repo: 'https://repo-url.com/helm-charts', // The Helm repository URL that hosts MapServer chart
    // If you require any custom values to be passed to the Helm chart, specify them here
    values: {
        service: {
            type: 'LoadBalancer',
        },
        // Any other custom values that MapServer Chart accepts
    },
    namespace: 'default', // The OpenShift namespace where you want to deploy MapServer
}, { provider: openshiftProvider });

// Optionally export any outputs.
export const mapserverServiceUrl = mapserverChart.getResourceProperty('v1/Service', 'mapserver-service-name', 'status').apply(status => status.loadBalancer.ingress[0].hostname);

```

Ensure you replace `'mapserver'`, `'x.y.z'`, `'https://repo-url.com/helm-charts'`, and `'mapserver-service-name'` with actual values that correspond to the MapServer Helm chart you wish to deploy. Also, adjust the custom values section according to your specific MapServer configuration needs.

Run `pulumi up` to deploy the MapServer Helm chart to your OpenShift cluster.

Keep in mind that accessing outputs like the hostname of a `Service` resource is subject to the resources created by the Helm chart and might require adjustments specific to the MapServer Helm chart you are using. For the official documentation on the Chart resource, you can visit [Pulumi's Chart documentation](https://www.pulumi.com/registry/packages/kubernetes/api-docs/helm.sh/v3/chart/).