Updated for a dryer test where the optional network layers can be proven out

Author: RussellGilmore

examples/existing-network/main.tf

@@ -0,0 +1,98 @@
+variable "project_name" {
+  type    = string
+  default = "red-instance-existing-net"
+}
+
+variable "region" {
+  type    = string
+  default = "us-east-1"
+}
+
+variable "instance_name" {
+  type    = string
+  default = "red-existing"
+}
+
+provider "aws" {
+  region = var.region
+}
+
+# A minimal network stood up in the example itself, standing in for any
+# externally-provided VPC (red-network, an existing corporate VPC, etc.).
+# This exercises red-instance's create_vpc = false path.
+resource "aws_vpc" "this" {
+  cidr_block           = "10.20.0.0/16"
+  enable_dns_support   = true
+  enable_dns_hostnames = true
+  tags                 = { Name = "${var.project_name}-vpc" }
+}
+
+resource "aws_internet_gateway" "this" {
+  vpc_id = aws_vpc.this.id
+  tags   = { Name = "${var.project_name}-igw" }
+}
+
+resource "aws_subnet" "public" {
+  vpc_id                  = aws_vpc.this.id
+  cidr_block              = "10.20.1.0/24"
+  map_public_ip_on_launch = true
+  availability_zone       = "${var.region}a"
+  tags                    = { Name = "${var.project_name}-public" }
+}
+
+resource "aws_route_table" "public" {
+  vpc_id = aws_vpc.this.id
+  route {
+    cidr_block = "0.0.0.0/0"
+    gateway_id = aws_internet_gateway.this.id
+  }
+  tags = { Name = "${var.project_name}-public-rt" }
+}
+
+resource "aws_route_table_association" "public" {
+  subnet_id      = aws_subnet.public.id
+  route_table_id = aws_route_table.public.id
+}
+
+module "red_instance" {
+  source = "../../"
+
+  project_name  = var.project_name
+  instance_name = var.instance_name
+
+  create_vpc = false
+  vpc_id     = aws_vpc.this.id
+  subnet_id  = aws_subnet.public.id
+
+  ingress_rules = [
+    {
+      description = "HTTPS from anywhere"
+      from_port   = 443
+      to_port     = 443
+      protocol    = "tcp"
+      cidr_blocks = ["0.0.0.0/0"]
+    }
+  ]
+
+  additional_tags = {
+    Environment = "example"
+  }
+}
+
+output "instance_id" {
+  value = module.red_instance.instance_id
+}
+
+output "public_ip" {
+  value = module.red_instance.public_ip
+}
+
+output "vpc_id" {
+  description = "VPC ID — should equal the externally-created VPC, not a module-created one."
+  value       = module.red_instance.vpc_id
+}
+
+output "supplied_vpc_id" {
+  description = "The externally-created VPC ID, for cross-checking against the module output."
+  value       = aws_vpc.this.id
+}