Support instance deletion protection (#56)

also bump google provider version to 3.57.0

modules/cloud-sql/main.tf

@@ -45,6 +45,9 @@ resource "google_sql_database_instance" "master" {
   region           = var.region
   database_version = var.engine
 
+  # Whether or not to allow Terraform to destroy the instance.
+  deletion_protection = var.deletion_protection
+
   settings {
     tier              = var.machine_type
     activation_policy = var.activation_policy
@@ -173,6 +176,9 @@ resource "google_sql_database_instance" "failover_replica" {
   # The name of the instance that will act as the master in the replication setup.
   master_instance_name = google_sql_database_instance.master.name
 
+  # Whether or not to allow Terraform to destroy the instance.
+  deletion_protection = var.deletion_protection
+
   replica_configuration {
     # Specifies that the replica is the failover target.
     failover_target = true
@@ -253,6 +259,9 @@ resource "google_sql_database_instance" "read_replica" {
   # The name of the instance that will act as the master in the replication setup.
   master_instance_name = google_sql_database_instance.master.name
 
+  # Whether or not to allow Terraform to destroy the instance.
+  deletion_protection = var.deletion_protection
+
   replica_configuration {
     # Specifies that the replica is not the failover target.
     failover_target = false

modules/cloud-sql/variables.tf

@@ -232,6 +232,13 @@ variable "resource_timeout" {
   default     = "60m"
 }
 
+# Whether or not to allow Terraform to destroy the instance.
+variable "deletion_protection" {
+  description = "Whether or not to allow Terraform to destroy the instance. Unless this field is set to false in Terraform state, a terraform destroy or terraform apply command that deletes the instance will fail."
+  type        = bool
+  default     = "true"
+}
+
 # ---------------------------------------------------------------------------------------------------------------------
 # MODULE DEPENDENCIES
 # Workaround Terraform limitation where there is no module depends_on.