feat(rds): add database_insights_mode (#195)

* feat(rds): add database_insights_mode

* fix: invalid null value

The value for `database_insights_mode` can only be one of: "standard" or "advanced"

* docs: updated database_insights_mode description

The description still identified null as a valid value when it is not.

---------

Co-authored-by: RoseSecurity <[email protected]>

Author: cdobbyn

main.tf

@@ -84,6 +84,7 @@ resource "aws_db_instance" "default" {
   performance_insights_enabled          = var.performance_insights_enabled
   performance_insights_kms_key_id       = var.performance_insights_enabled ? var.performance_insights_kms_key_id : null
   performance_insights_retention_period = var.performance_insights_enabled ? var.performance_insights_retention_period : null
+  database_insights_mode                = var.database_insights_mode
 
   monitoring_interval = var.monitoring_interval
   monitoring_role_arn = var.monitoring_role_arn

variables.tf

@@ -315,6 +315,17 @@ variable "performance_insights_retention_period" {
   description = "The amount of time in days to retain Performance Insights data. Either 7 (7 days) or 731 (2 years)."
 }
 
+variable "database_insights_mode" {
+  type        = string
+  default     = "standard"
+  nullable    = false
+  description = "The mode for CloudWatch Database Insights. Valid values: 'standard' or 'advanced'."
+  validation {
+    condition     = contains(["standard", "advanced"], var.database_insights_mode)
+    error_message = "database_insights_mode must be one of: 'standard' (free) or 'advanced'."
+  }
+}
+
 variable "enabled_cloudwatch_logs_exports" {
   type        = list(string)
   default     = []

versions.tf

@@ -4,7 +4,7 @@ terraform {
   required_providers {
     aws = {
       source  = "hashicorp/aws"
-      version = ">= 5.0"
+      version = ">= 5.92.0"
     }
   }
 }