Define IPs which have access to the kubernetes-API and SSH as variables

I liked the idea to have these IPs dynamically detected at runtime,
though some research showed that my current provider only renews these
every 180 days, nowadays. So, no need for such a hyper-dynamic solution.
Instead I use a variable now, which brings some other benefits, like
adding arbitrary IPs as well. This might become handy in cases of CI/CD.

main.tf

@@ -24,14 +24,6 @@ resource "hcloud_primary_ip" "k8s_ipv6" {
   auto_delete   = !var.k8s_test_installation
 }
 
-data "external" "my_ip" {
-  program = [
-    "sh",
-    "-c",
-    "(dig TXT +short -4 o-o.myaddr.l.google.com @ns1.google.com && dig TXT +short -6 o-o.myaddr.l.google.com @ns1.google.com) | jq '{(.): .}' | jq -s add"
-  ]
-}
-
 module "k8s" {
   source = "./modules/hetzner/kubernetes"
 
@@ -48,8 +40,8 @@ module "k8s" {
     location = var.k8s_location
     count    = var.k8s_agent_count
   }]
-  kubernetes_exposed_ips = var.expose_kubernetes_and_ssh_ports ? values(data.external.my_ip.result) : []
-  ssh_exposed_ips        = var.expose_kubernetes_and_ssh_ports ? values(data.external.my_ip.result) : []
+  kubernetes_exposed_ips = var.kubernetes_allowed_ips
+  ssh_exposed_ips        = var.ssh_allowed_ips
   ssh_port               = 1022
   public_tcp_services = {
     git-ssh = ["22"]

variables.tf

@@ -1,6 +1,11 @@
-variable "expose_kubernetes_and_ssh_ports" {
-  type    = bool
-  default = false
+variable "kubernetes_allowed_ips" {
+  type        = set(string)
+  description = "A set of IPs (IPv4 and IPv6) which have access to the kubernetes API."
+}
+
+variable "ssh_allowed_ips" {
+  type        = set(string)
+  description = "A set of IPs (IPv4 and IPv6) which can access the cluster via SSH."
 }
 
 variable "hetzner_dns_apitoken" {

versions.tf

@@ -26,10 +26,6 @@ terraform {
       source  = "hashicorp/random"
       version = "3.7.1"
     }
-    external = {
-      source  = "hashicorp/external"
-      version = "2.3.4"
-    }
   }
 }
 
@@ -42,4 +38,3 @@ provider "hcloud" {
 }
 
 provider "random" {}
-provider "external" {}