fix: Worker security group handling when worker_create_security_group=false (#1461)

Author: sunghospark-calm

cluster.tf

@@ -80,7 +80,7 @@ resource "aws_security_group_rule" "cluster_egress_internet" {
 }
 
 resource "aws_security_group_rule" "cluster_https_worker_ingress" {
-  count                    = var.cluster_create_security_group && var.create_eks ? 1 : 0
+  count                    = var.cluster_create_security_group && var.create_eks && var.worker_create_security_group ? 1 : 0
   description              = "Allow pods to communicate with the EKS cluster API."
   protocol                 = "tcp"
   security_group_id        = local.cluster_security_group_id

modules/node_groups/launch_template.tf

@@ -52,15 +52,15 @@ resource "aws_launch_template" "workers" {
   network_interfaces {
     associate_public_ip_address = lookup(each.value, "public_ip", null)
     delete_on_termination       = lookup(each.value, "eni_delete", null)
-    security_groups = flatten([
+    security_groups = compact(flatten([
       var.worker_security_group_id,
       var.worker_additional_security_group_ids,
       lookup(
         each.value,
         "additional_security_group_ids",
         null,
       ),
-    ])
+    ]))
   }
 
   # if you want to use a custom AMI