Find right AMI for instance architecture

The AMI for dev desktops is now selected based on the architecture of
the instance.

Author: jdno

terraform/dev-desktops/aws-region/_terraform.tf

@@ -10,6 +10,7 @@ terraform {
 variable "instances" {
   type = map(object({
     instance_type = string
+    instance_arch = string
     storage       = number
   }))
 }

terraform/dev-desktops/aws-region/instances.tf

@@ -3,7 +3,7 @@
 resource "aws_instance" "instance" {
   for_each = var.instances
 
-  ami                     = data.aws_ami.instance.id
+  ami                     = data.aws_ami.instance[each.value.instance_arch].id
   instance_type           = each.value.instance_type
   key_name                = aws_key_pair.instance.key_name
   ebs_optimized           = true
@@ -32,12 +32,14 @@ resource "aws_instance" "instance" {
 }
 
 data "aws_ami" "instance" {
+  for_each = toset(values(var.instances)[*].instance_arch)
+
   most_recent = true
   owners      = ["099720109477"] # Canonical
 
   filter {
     name   = "name"
-    values = ["ubuntu/images/hvm-ssd/ubuntu-jammy-22.04-arm64-server-*"]
+    values = ["ubuntu/images/hvm-ssd/ubuntu-jammy-22.04-${each.key}-server-*"]
   }
 
   filter {

terraform/dev-desktops/regions.tf

@@ -7,10 +7,12 @@ module "aws_eu_central_1" {
   instances = {
     "dev-desktop-staging" = {
       instance_type = "t3a.micro"
+      instance_arch = "amd64"
       storage       = 25
     }
     "dev-desktop-eu-1" = {
       instance_type = "c6g.8xlarge"
+      instance_arch = "arm64"
       storage       = 1000
     }
   }
@@ -25,6 +27,7 @@ module "aws_us_east_1" {
   instances = {
     "dev-desktop-us-1" = {
       instance_type = "c7g.8xlarge"
+      instance_arch = "arm64"
       storage       = 1000
     }
   }