Deploy the mongodb-replicaset helm chart on Rancher

Question

Pulumi · Accepted Answer

To deploy the `mongodb-replicaset` Helm chart on Rancher, we need to follow a set of steps. First, let's ensure the environment is prepared for our deployment:

1. Set up a Kubernetes cluster in Rancher.
2. Make sure you have Helm installed in your Rancher Kubernetes cluster. Helm is a package manager for Kubernetes, we'll use it to install the `mongodb-replicaset` chart.
3. Configure Pulumi to communicate with Rancher.
4. Write a Pulumi program to deploy the Helm chart.

Let's break down these steps.

### Pre-requisites:
- A Rancher Server set up and managed Kubernetes cluster where your Helm chart will be deployed.
- The `rancher2` Pulumi provider properly installed and configured to interact with the Rancher Kubernetes cluster.
- The Helm CLI also needs to be installed in your environment if you need to customize the Helm chart or use Helm to confirm the status of your deployments directly.

### Step-by-Step Code Explanation:

In the Pulumi program below, we'll use the `rancher2` provider to deploy a Helm chart. Important steps include importing the necessary Pulumi packages, configuring the provider to interact with our Rancher instance, and using a Pulumi resource to deploy the Helm chart.

Here's a TypeScript program that you can use to accomplish the deployment:

```typescript
import * as rancher2 from "@pulumi/rancher2";
import * as kubernetes from "@pulumi/kubernetes";
import * as pulumi from "@pulumi/pulumi";

// Initialize a Pulumi stack configuration
const config = new pulumi.Config();

// Retrieve cluster configuration
const clusterId = config.require('clusterId'); // The ID of your managed Kubernetes cluster in Rancher

// Initialize provider to interact with the specific Rancher cluster
const provider = new rancher2.Provider("rancher", {
    apiUrl: "https://rancher.my-domain.com/v3", // Replace with your Rancher API URL
    tokenKey: "token-ABC123DEF456", // Replace with your Rancher API Bearer Token
    clusterId: clusterId,
    // pools name and quantity can be synced from Rancher 2 Cloud Cluster configuration
});

// Deploy the mongodb-replicaset Helm chart using the rancher2 provider
const mongodbReplicaset = new kubernetes.helm.v3.Chart("mongodb-replicaset", {
    // Reference to the Rancher Kubernetes cluster provider
    // This is necessary for Helm to communicate with the Kubernetes API server
    // that Rancher manages.
    provider: provider.k8sProvider,

// We specify the Helm chart details, including repository information,
    // chart name, and version. We can also include any custom values we need
    // to configure our MongoDB replica set.
    chart: "mongodb-replicaset",
    version: "3.9.1", // specify the chart version
    repositoryOpts: {
        repo: "https://charts.bitnami.com/bitnami",
    },
    values: {
        // Provide custom values for your mongodb-replicaset Helm chart,
        // such as replica count, resource specifications, and so on.
        // By default, we'll use the chart's default values.
    }
}, { dependsOn: [provider] });

// Export the MongoDB Replica Set endpoint for easy access
export const mongodbEndpoint = pulumi.output(mongodbReplicaset.getResourceProperty("v1/Service", "mongodb-replicaset", "status"))
    .apply(status => status.loadBalancer.ingress[0].ip);

// Run `pulumi up` to deploy your chart to the cluster.
```

In the above program:

- We first import the necessary Pulumi libraries for interacting with Rancher (`rancher2`) and Kubernetes (`kubernetes`).
- We then create a new `rancher2.Provider`, specifying the API URL and token for your Rancher server, as well as the ID of your Kubernetes cluster.
- After that, we define the `mongodb-replicaset` Helm chart, setting the chart name, version, and any specific configurations.
- Lastly, we export a computed endpoint for the MongoDB service, which allows us to connect to our MongoDB replica set from outside the Kubernetes cluster.

### Important:
- Replace the `apiUrl` with the endpoint of your Rancher server.
- Replace the `tokenKey` with your token from the Rancher Server API (bearer token).
- Replace the `clusterId` with the ID of the Kubernetes cluster managed by Rancher where you want to deploy the Helm chart.

Once you have this Pulumi program, run `pulumi up` to execute it. This will perform the deployment as per your configuration. Make sure you have Pulumi installed and configured with the correct credentials to access your cloud resources.

After successful deployment, you can use the exported `mongodbEndpoint` to interact with your MongoDB replica set.