refact: clean custom flags feature

README.md

@@ -17,7 +17,15 @@ module "k3s" {
   cluster_service_cidr = "10.1.0.0/16"
   additional_tls_san = ["k3s.my.domain.com"]
 
-  custom_server_args = ["-v 10"]
+  additional_flags = {
+    master = []
+    minion = [
+      "--node-label node-role.kubernetes.io/minion='true'",
+    ]
+    common = [
+      "--no-flannel"
+    ]
+  }
   
   master_node = {
       # This IP will be used as k3s master node IP.... if you want to use a public

examples/hcloud-k3s/main.tf

@@ -12,13 +12,15 @@ module "k3s" {
   cluster_service_cidr = "10.1.0.0/16"
   drain_timeout        = "30s"
 
-  custom_server_args = [
-    "--kube-cloud-controller-manager-arg hcloud"
-  ]
-  custom_agent_args = [
-    "-v 10",
-    "--no-flannel"
-  ]
+  additional_flags = {
+    master = []
+    minion = [
+      "--node-label node-role.kubernetes.io/minion='true'",
+    ]
+    common = [
+      "--no-flannel"
+    ]
+  }
 
   master_node = {
     ip = hcloud_server_network.master_network.ip

master.tf

@@ -20,8 +20,8 @@ locals {
       "--service-cidr ${var.cluster_service_cidr}",
       local.tls_san_opts,
     ],
-    var.custom_server_args,
-    var.custom_agent_args
+    var.additional_flags.master,
+    var.additional_flags.common,
   )
   master_install_args = join(" ", local.master_install_arg_list)
 

minions.tf

@@ -1,6 +1,9 @@
 locals {
-  minion_install_arg_list = var.custom_agent_args
-  minion_install_args     = join(" ", local.minion_install_arg_list)
+  minion_install_arg_list = concat(
+    var.additional_flags.minion,
+    var.additional_flags.common,
+  )
+  minion_install_args = join(" ", local.minion_install_arg_list)
 
   minion_install_env_list = [
     "INSTALL_K3S_VERSION=${local.k3s_version}",

variables.tf

@@ -28,16 +28,18 @@ variable "additional_tls_san" {
   default     = []
 }
 
-variable "custom_server_args" {
-  description = "Additional K3S server commands. (see https://rancher.com/docs/k3s/latest/en/installation/install-options/#k3s-server)"
-  type        = list(string)
-  default     = []
-}
-
-variable "custom_agent_args" {
-  description = "Additional K3S agent commands. (see https://rancher.com/docs/k3s/latest/en/installation/install-options/#k3s-agent)"
-  type        = list(string)
-  default     = []
+variable "additional_flags" {
+  description = "Add additional flags during the k3s installation (see https://rancher.com/docs/k3s/latest/en/installation/install-options/)."
+  type = object({
+    master = list(string)
+    minion = list(string)
+    common = list(string)
+  })
+  default = {
+    master = []
+    minion = []
+    common = []
+  }
 }
 
 variable "master_node" {