How Do I Configure a Kubernetes Networking.istio.io Serviceentry With Pulumi?

In this guide, we will configure an Istio ServiceEntry resource in a Kubernetes cluster using Pulumi. The ServiceEntry resource is used to add additional entries to Istio’s internal service registry, allowing Istio to manage traffic to services that are not part of the mesh.

Key Points:

• We will use Pulumi to define and deploy the ServiceEntry resource.
• The ServiceEntry will allow Istio to route traffic to an external service.

Below is the Pulumi program written in TypeScript to achieve this.

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

// Define the ServiceEntry resource
const serviceEntry = new k8s.apiextensions.CustomResource("example-serviceentry", {
    apiVersion: "networking.istio.io/v1alpha3",
    kind: "ServiceEntry",
    metadata: {
        name: "example-serviceentry",
        namespace: "default",
    },
    spec: {
        hosts: ["example.com"],
        ports: [
            {
                number: 80,
                name: "http",
                protocol: "HTTP",
            },
        ],
        resolution: "DNS",
        location: "MESH_EXTERNAL",
    },
});

export const serviceEntryName = serviceEntry.metadata.name;

Explanation:

1. Import Modules: We import the necessary Pulumi and Kubernetes modules.
2. Define ServiceEntry: We create a new ServiceEntry custom resource.
   • apiVersion: Specifies the API version of the ServiceEntry.
   • kind: Specifies the kind of the resource, which is ServiceEntry.
   • metadata: Contains metadata about the resource, including its name and namespace.
   • spec: Defines the specification of the ServiceEntry, including the hosts, ports, resolution method, and location.

Conclusion:

We have successfully configured an Istio ServiceEntry using Pulumi. This configuration allows Istio to route traffic to the specified external service. By using Pulumi, we can manage our Kubernetes resources with code, making our infrastructure more maintainable and version-controlled.