fix: Add opt-in config to create order independent log filters

modules/cloudwatch-logs/main.tf

@@ -23,10 +23,21 @@ module "kfh" {
 }
 
 resource "aws_cloudwatch_log_subscription_filter" "this" {
-  count           = length(var.cloudwatch_log_groups)
+  count           = !var.use_order_independent_filter_resource_naming ? length(var.cloudwatch_log_groups) : 0
+
   name            = "${var.cloudwatch_log_groups[count.index]}-logs_subscription_filter"
   role_arn        = aws_iam_role.this.arn
   log_group_name  = var.cloudwatch_log_groups[count.index]
   filter_pattern  = var.log_subscription_filter_pattern
   destination_arn = module.kfh.kinesis_firehose_delivery_stream_arn
 }
+
+resource "aws_cloudwatch_log_subscription_filter" "filters" {
+  for_each = var.use_order_independent_filter_resource_naming ? toset(var.cloudwatch_log_groups) : []
+
+  name            = "${each.key}-logs_subscription_filter"
+  role_arn        = aws_iam_role.this.arn
+  log_group_name  = each.key
+  filter_pattern  = var.log_subscription_filter_pattern
+  destination_arn = module.kfh.kinesis_firehose_delivery_stream_arn
+}

modules/cloudwatch-logs/outputs.tf

@@ -1,3 +1,3 @@
 output "cloudwatch_log_subscription_filters" {
-  value = aws_cloudwatch_log_subscription_filter.this[*].name
+  value = var.use_order_independent_filter_resource_naming ? [for filter in aws_cloudwatch_log_subscription_filter.filters : filter.name] : aws_cloudwatch_log_subscription_filter.this[*].name
 }

modules/cloudwatch-logs/variables.tf

@@ -136,3 +136,9 @@ variable "tags" {
   default     = {}
   description = "A map of tags to apply to resources created by this module."
 }
+
+variable "use_order_independent_filter_resource_naming" {
+  type        = bool
+  description = "Use order-independent naming for log group subscription filter resources."
+  default     = false
+}