Added some basic variable validation

modules/dns/variables.tf

@@ -97,6 +97,10 @@ variable "type" {
   description = "Type of zone to create, valid values are 'public', 'private', 'forwarding', 'peering', 'service-directory'."
   type        = string
   default     = "private"
+  validation {
+    condition     = contains(["public", "private", "forwarding", "peering", "service-directory"], var.type)
+    error_message = "Zone must be one of 'public', 'private', 'forwarding', 'peering', 'service-directory'."
+  }
 }
 
 variable "zone_create" {
@@ -106,3 +110,4 @@ variable "zone_create" {
 }
 
 
+

modules/gcs/variables.tf

@@ -88,6 +88,10 @@ variable "storage_class" {
   description = "Bucket storage class."
   type        = string
   default     = "MULTI_REGIONAL"
+  validation {
+    condition     = contains(["STANDARD", "MULTI_REGIONAL", "REGIONAL", "NEARLINE", "COLDLINE", "ARCHIVE"], var.storage_class)
+    error_message = "Storage class must be one of STANDARD, MULTI_REGIONAL, REGIONAL, NEARLINE, COLDLINE, ARCHIVE."
+  }
 }
 
 variable "versioning" {

modules/net-vpc/variables.tf

@@ -100,6 +100,11 @@ variable "routing_mode" {
   description = "The network routing mode (default 'GLOBAL')"
   type        = string
   default     = "GLOBAL"
+  validation {
+    condition     = var.routing_mode == "GLOBAL" || var.routing_mode == "REGIONAL"
+    error_message = "Routing type must be GLOBAL or REGIONAL."
+  }
+
 }
 
 variable "shared_vpc_host" {

modules/project/variables.tf

@@ -83,6 +83,10 @@ variable "parent" {
   description = "Parent folder or organization in 'folders/folder_id' or 'organizations/org_id' format."
   type        = string
   default     = null
+  validation {
+    condition     = can(regex("(organizations|folders)/[0-9]+", var.parent))
+    error_message = "Parent must be of the form folders/folder_id or organizations/organization_id."
+  }
 }
 
 variable "policy_boolean" {