Adding exchange module for AWS Terraform

AWS/Terraform/modules/exchange/variables.tf

@@ -0,0 +1,38 @@
+variable "security_group_id" {
+  type = list(string)
+}
+
+variable "subnet_id" {
+  type = string
+}
+
+variable "instance_name_prefix" {
+  type = string
+}
+
+variable "region" {
+  type    = string
+  default = ""
+}
+
+variable "custom-tags" {
+  type = map(string)
+  description = "Optional mapping for additional tags to apply to all related AWS resources"
+  default = {}
+}
+
+variable "exchange_ami" {
+  type    = string
+  default = ""
+}
+
+# Use Data Sources to resolve the AMI-ID for the pre-built EXCHANGE host
+data "aws_ami" "exchange_ami" {
+  owners      = ["505638924199"]
+  most_recent = true
+
+  filter {
+    name   = "name"
+    values = ["detectionlab-exchange"]
+  }
+}