Ignore changes to names for CF imported resources (#244)

When migrating from Cloudformation to Terraform there are resources that
are named differently and can't be renamed. The DB for example.

This change tells terraform to ignore changes to the names in the case
where CF resources with different naming patterns are imported into
Terraform state. This will prevent terraform from trying to recreate it.

Author: mdeeks

modules/database/main.tf

@@ -58,7 +58,8 @@ resource "aws_db_instance" "main" {
       identifier,
       kms_key_id,
       storage_encrypted,
-      db_subnet_group_name
+      db_subnet_group_name,
+      db_name
     ]
   }
 }
@@ -98,6 +99,7 @@ resource "aws_db_parameter_group" "main" {
 
   lifecycle {
     create_before_destroy = true
+    ignore_changes        = [name_prefix, description]
   }
 
   tags = local.common_tags
@@ -111,6 +113,7 @@ resource "aws_db_subnet_group" "main" {
 
   lifecycle {
     create_before_destroy = true
+    ignore_changes        = [name_prefix]
   }
 
   tags = local.common_tags
@@ -134,6 +137,10 @@ resource "aws_iam_role" "db_monitoring" {
 
   permissions_boundary = var.permissions_boundary_arn
 
+  lifecycle {
+    ignore_changes = [name]
+  }
+
   tags = local.common_tags
 }
 
@@ -165,6 +172,10 @@ resource "aws_secretsmanager_secret" "database_secret" {
   description = "Username/password for the main Braintrust RDS database"
   kms_key_id  = var.kms_key_arn
 
+  lifecycle {
+    ignore_changes = [name, name_prefix]
+  }
+
   tags = local.common_tags
 }
 

modules/services-common/secrets.tf

@@ -4,6 +4,10 @@ resource "aws_secretsmanager_secret" "function_tools_secret" {
   description = "Function environment variables encryption key"
   kms_key_id  = var.kms_key_arn
   tags        = local.common_tags
+
+  lifecycle {
+    ignore_changes = [name, name_prefix]
+  }
 }
 
 data "aws_secretsmanager_random_password" "function_tools_secret" {