How to automatically add a domain to a LoadBalancer Service on Kubernetes using Terraform?

GOAL: I’m using terraform to quickly and easily setup a Kubernetes cluster. I have a LoadBalancer service that should expose my blog-backend service with a custom domain (I have already added DNS NS entries in my Cloudflare that redirects base domain to DigitalOcean’s servers).

resource "kubernetes_service" "blog-backend-lb" {
  metadata {
    name = "blog-backend-lb"
    labels = {
      app = "blog-backend"
    }
    annotations = {
      "service.beta.kubernetes.io/do-loadbalancer-name" = "blog.mydomain.com"
      "service.beta.kubernetes.io/do-loadbalancer-hostname" = "blog.mydomain.com"
    }
  }
  spec {
    type = "LoadBalancer"

    selector = {
      app = "blog-backend"
    }

    port {
      port = 8080
      target_port = 8080
    }
  }
}

PROBLEM: The service is being create properly and I can see Kubernetes picked up a domain.

041

However, I cannot access it unless I manually create a domain entry in the DigitalOcean dashboard: Networking -> Domains -> Add Domain -> Create Record for my subdomain redirecting to a LoadBalancer.

This is a bit cumbersome, because I want to clean everything up using terraform without touching anything by hand.

QUESTION: How can I automate it using a Terraform?

I thought about using a domain resource, but I don’t know where to get the ip address from.

resource "digitalocean_domain" "blog-backend-domain" {
  name = "blog.mydomain.com"
  ip_address = "<WHERE TO GET THE IP FROM?>"
}