Using kubernetes kubernetes-client.io with traefik.io

Question

Pulumi · Accepted Answer

To use Kubernetes client (`kubernetes-client.io`) with `traefik.io` as an ingress controller, you'll need to set up Traefik as the Ingress controller in your Kubernetes cluster. Traefik is a modern HTTP reverse proxy and load balancer that makes deploying microservices easy. It handles incoming requests and routes them to the appropriate services within a Kubernetes cluster.

To accomplish this with Pulumi, you must follow these steps:

1. Deploy Traefik as an Ingress controller to your Kubernetes cluster.
2. Define an Ingress resource that specifies how the incoming traffic should be routed to your services.

Below is a Pulumi program written in TypeScript that deploys Traefik as an Ingress controller using the `kubernetes-ingress-nginx` Pulumi package and sets up a basic Ingress to route traffic based on hostnames or paths. Note that the actual service details and traffic routing rules will vary depending on your application's requirements.

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

// Create a namespace for the Ingress controller
const ns = new k8s.core.v1.Namespace("ingress-ns", {
    metadata: { name: "traefik" },
});

// Deploy Traefik using Helm
const traefik = new k8s.helm.v3.Chart("traefik-ingress", {
    chart: "traefik",
    version: "10.3.0", // Use the correct version for your setup
    namespace: ns.metadata.name,
    fetchOpts:{
        repo: "https://helm.traefik.io/traefik",
    },
}, { dependsOn: [ns] });

// Define an Ingress to route traffic to a mock-service based on hostname
const ingress = new k8s.networking.v1.Ingress("example-ingress", {
    metadata: {
        namespace: ns.metadata.name,
        name: "example-ingress",
        annotations: {
            "kubernetes.io/ingress.class": "traefik",
        },
    },
    spec: {
        rules: [{
            host: "myapp.example.com",
            http: {
                paths: [{
                    path: "/",
                    pathType: "Prefix",
                    backend: {
                        service: {
                            name: "mock-service", // Replace with your actual service name
                            port: {
                                number: 80, // Replace with the port your service listens on
                            },
                        },
                    },
                }],
            },
        }],
    },
}, { dependsOn: [traefik] });

// Export the Traefik Ingress endpoint
export const ingressEndpoint = traefik.getResourceProperty("v1/Service", "traefik-ingress-controller", "status");

```

### Explanation:

- First, we create a new namespace called `traefik` for the Ingress resources using the `k8s.core.v1.Namespace` class from the Pulumi Kubernetes SDK.

- We then deploy Traefik as a Helm chart, specifying the chart version and Helm repository URL. The deployment is contained in the previously created namespace (`traefik`), and we set a dependency to ensure that the namespace is created before attempting to deploy the chart.

- Next, we create an Ingress resource using `k8s.networking.v1.Ingress`. This resource defines rules for routing traffic to services within the cluster. In this example, traffic to the `myapp.example.com` domain is routed to a service named `mock-service` on port `80`. The `mock-service` service is a placeholder, you would replace it with the actual service that you want to expose via Traefik.

- Finally, we export the Ingress endpoint status using Pulumi's `getResourceProperty` function to query the Traefik Ingress service once it is deployed to obtain its external endpoint.

### What to do next:

Deploy the Pulumi program in your development environment. If you haven't done so already, install the Pulumi CLI, set up your Kubernetes cluster, and configure the Kubernetes provider for Pulumi. Then, run `pulumi up` to execute your program and set up Traefik as your Ingress controller on the Kubernetes cluster.

Be aware of the following:

- You may need to adjust the deployment specifics, such as chart versions and service details, to match your environment and needs.

- The above example assumes a service called `mock-service` exists in your cluster. You'll need to replace this with your actual service name and port.

- The ingress resource example uses a simple hostname path routing rule. You might need more complex routing if you have additional requirements.

By following the above steps and deploying this Pulumi program, Traefik will handle incoming requests and route them to the correct Kubernetes services based on the ingress rules you set.