adding tgw-static-routes module (#187)

modules/aws/networking/tgw-static-routes/main.tf

@@ -0,0 +1,25 @@
+
+# Data resource to fetch the existing TGW route table by name or ID
+data "aws_ec2_transit_gateway_route_table" "tgw_rt" {
+  #id = var.tgw_route_table_id
+  filter {
+    name   = "tag:Name"
+    values = [var.tgw_route_table_name]  # Can be fetched or passed from Terragrunt
+  }
+}
+
+# Read routes from the text file (routes.json)
+locals {
+  routes = jsondecode(var.static_routes_file)
+}
+
+# Add static routes to the TGW route table using the data from the text file
+resource "aws_ec2_transit_gateway_route" "tgw_routes" {
+  for_each = { for route in local.routes["routes"] : route.cidr_block => route }
+
+  transit_gateway_route_table_id = data.aws_ec2_transit_gateway_route_table.tgw_rt.id
+  destination_cidr_block         = each.value.cidr_block
+  transit_gateway_attachment_id  = each.value.transit_gateway_attachment_id
+}
+
+

modules/aws/networking/tgw-static-routes/variables.tf

@@ -0,0 +1,14 @@
+variable "tgw_route_table_id" {
+  description = "The Transit Gateway Route Table ID."
+  type        = string
+}
+
+variable "tgw_route_table_name" {
+  description = "The Transit Gateway Route Table Name."
+  type        = string
+}
+
+variable static_routes_file {
+    description = "A list of static routes to supply in a file"
+    type        = string
+}