Merge pull request #78 from lowescott/module1

Add an example of using Terraform modules

terraform/aws/README.md

@@ -12,6 +12,8 @@ This directory contains a number of subdirectories with example configurations i
 
 * **simple-ec2**: This directory contains a simple Terraform configuration for spinning up an Ubuntu 14.04 EC2 instance in an account's default VPC.
 
+* **simple-module**: This directory contains a very simple example of using a Terraform module for more reusable code blocks.
+
 ## Prerequisites
 
 These instructions assume you've already installed Terraform and that you have access to a valid AWS account. Installing Terraform and/or working with AWS accounts are not covered in any of these materials.

terraform/aws/simple-module/main.tf

@@ -0,0 +1,23 @@
+module "vpc20" {
+    source                  = "./modules/vpc"
+
+    name                    = "test-vpc-1"
+    vpc_cidr_block          = "10.20.0.0/16"
+    vpc_dns_hostnames       = "true"
+    vpc_dns_support         = "true"
+
+    subnet_cidr_block       = "10.20.1.0/24"
+    subnet_map_pub_ip       = "true"    
+}
+
+module "vpc50" {
+    source                  = "./modules/vpc"
+
+    name                    = "test-vpc-2"
+    vpc_cidr_block          = "10.50.0.0/16"
+    vpc_dns_hostnames       = "true"
+    vpc_dns_support         = "true"
+
+    subnet_cidr_block       = "10.50.1.0/24"
+    subnet_map_pub_ip       = "true"    
+}

terraform/aws/simple-module/modules/vpc/main.tf

@@ -0,0 +1,36 @@
+# Create a new VPC
+resource "aws_vpc" "vpc" {
+    cidr_block              = "${var.vpc_cidr_block}"
+    enable_dns_hostnames    = "${var.vpc_dns_hostnames}"
+    enable_dns_support      = "${var.vpc_dns_support}"
+}
+
+# Create a public subnet in the new VPC
+resource "aws_subnet" "subnet" {
+    vpc_id                  = "${aws_vpc.vpc.id}"
+    cidr_block              = "${var.subnet_cidr_block}"
+    map_public_ip_on_launch = "${var.subnet_map_pub_ip}"
+}
+
+# Create a new Internet gateway
+resource "aws_internet_gateway" "gateway" {
+    vpc_id                  = "${aws_vpc.vpc.id}"
+}
+
+# Create a route table for the new VPC
+resource "aws_route_table" "routes" {
+    vpc_id                  = "${aws_vpc.vpc.id}"
+}
+
+# Create a route in new route table
+resource "aws_route" "default_route" {
+    route_table_id          = "${aws_route_table.routes.id}"
+    destination_cidr_block  = "0.0.0.0/0"
+    gateway_id              = "${aws_internet_gateway.gateway.id}"
+}
+
+# Associate route table with subnet in VPC
+resource "aws_route_table_association" "rte_tbl_assoc" {
+    subnet_id               = "${aws_subnet.subnet.id}"
+    route_table_id          = "${aws_route_table.routes.id}"
+}

terraform/aws/simple-module/modules/vpc/output.tf

@@ -0,0 +1,11 @@
+output "new_vpc_id" {
+    value                   = "${aws_vpc.vpc.id}"
+}
+
+output "new_subnet_id" {
+    value                   = "${aws_subnet.subnet.id}"
+}
+
+output "new_subnet_az" {
+    value                   = "${aws_subnet.subnet.availability_zone}"
+}

terraform/aws/simple-module/modules/vpc/variables.tf

@@ -0,0 +1,29 @@
+variable "name" {
+    type                    = "string"
+    description             = "Name prefix to use for networking resources"
+}
+
+variable "vpc_cidr_block" {
+    type                    = "string"
+    description             = "CIDR block to use for new VPC"
+}
+
+variable "vpc_dns_hostnames" {
+    type                    = "string"
+    description             = "True/False to enable DNS hostnames in new VPC"
+}
+
+variable "vpc_dns_support" {
+    type                    = "string"
+    description             = "True/False to enable DNS support in new VPC"
+}
+
+variable "subnet_cidr_block" {
+    type                    = "string"
+    description             = "CIDR block (in VPC CIDR block) to use for new subnet"
+}
+
+variable "subnet_map_pub_ip" {
+    type                    = "string"
+    description             = "True/False to map public IP addresses on launch"
+}

terraform/aws/simple-module/provider.tf

@@ -0,0 +1,3 @@
+provider "aws" {
+    region                  = "${var.user_region}"
+}

terraform/aws/simple-module/variables.tf

@@ -0,0 +1,4 @@
+variable "user_region" {
+    type                    = "string"
+    description             = "AWS region to use for all resources"
+}