update to 0.12 syntax

Author: akerl

main.tf

@@ -8,15 +8,16 @@ module "vm" {
   name            = "algo-image_${random_id.vm_suffix.hex}"
   region          = "us-east"
   type            = "g6-standard-1"
-  algo_repo       = "${var.algo_repo}"
+  algo_repo       = var.algo_repo
   source_image_id = "linode/ubuntu18.04"
-  ssh_keys        = ["${var.ssh_keys}"]
-  ssh_users       = ["${var.ssh_users}"]
+  ssh_keys        = [var.ssh_keys]
+  ssh_users       = [var.ssh_users]
 }
 
 resource "linode_image" "image" {
-  linode_id   = "${module.vm.linode_id}"
-  disk_id     = "${module.vm.disk_id}"
+  linode_id   = module.vm.linode_id
+  disk_id     = module.vm.disk_id
   label       = "algo-image"
   description = "Created by Terraform"
 }
+

outputs.tf

@@ -1,4 +1,5 @@
 output "image_id" {
-  value       = "${linode_image.image.id}"
+  value       = linode_image.image.id
   description = "ID of the Algo Image"
 }
+

variables.tf

@@ -1,17 +1,18 @@
 variable "algo_repo" {
-  type        = "string"
+  type        = string
   default     = "https://github.com/akerl/algo"
   description = "Repo to use for Algo code"
 }
 
 variable "ssh_keys" {
-  type        = "list"
+  type        = list(string)
   description = "SSH public keys used to log in as root to the server"
   default     = []
 }
 
 variable "ssh_users" {
-  type        = "list"
+  type        = list(string)
   description = "List of authorized users (Linode usernames, must have keys already assigned via Linode API)"
   default     = []
 }
+