Fix error about applying windows to instances (#12)

Author: max-rocket-internet

main.tf

@@ -63,8 +63,8 @@ resource "aws_rds_cluster_instance" "instance" {
   publicly_accessible             = var.publicly_accessible
   db_subnet_group_name            = aws_db_subnet_group.main[0].name
   db_parameter_group_name         = var.db_parameter_group_name
-  preferred_backup_window         = var.preferred_backup_window
-  preferred_maintenance_window    = var.preferred_maintenance_window
+  preferred_backup_window         = var.preferred_backup_window_instance
+  preferred_maintenance_window    = var.preferred_maintenance_window_instance
   apply_immediately               = var.apply_immediately
   monitoring_role_arn             = join("", aws_iam_role.rds_enhanced_monitoring.*.arn)
   monitoring_interval             = var.monitoring_interval

variables.tf

@@ -85,15 +85,25 @@ variable "backup_retention_period" {
 }
 
 variable "preferred_backup_window" {
-  description = "When to perform DB backups"
+  description = "When to perform DB backups for the cluster"
   default     = "02:00-03:00"
 }
 
 variable "preferred_maintenance_window" {
-  description = "When to perform DB maintenance"
+  description = "When to perform DB maintenance for the cluster"
   default     = "sun:05:00-sun:06:00"
 }
 
+variable "preferred_backup_window_instance" {
+  description = "When to perform DB backups for instances"
+  default     = ""
+}
+
+variable "preferred_maintenance_window_instance" {
+  description = "When to perform DB maintenance for instances"
+  default     = ""
+}
+
 variable "port" {
   description = "The port on which to accept connections"
   default     = ""