Add Redshift subnets (#54)

* add cidr_block outputs to public and private subnets

* add cidr_block outputs to database and elasticache subnets

* add redshift subnet option

* fix tag

* add missing route association for redshift

* add vpc_endpoint_s3_pl_id and vpc_endpoint_dynamodb_pl_id outputs

* add redshift to complete-vcp example

* fix domain_name_servers - keep it a list

* fix outputs for TF 0.11

* fix missing *

* Minor corrections in example and in type of dhcp_options_domain_name_servers

* Minor corrections in example

* Updated README

README.md

@@ -17,6 +17,7 @@ These types of resources are supported:
 * [VPC Endpoint](https://www.terraform.io/docs/providers/aws/r/vpc_endpoint.html) (S3 and DynamoDB)
 * [RDS DB Subnet Group](https://www.terraform.io/docs/providers/aws/r/db_subnet_group.html)
 * [ElastiCache Subnet Group](https://www.terraform.io/docs/providers/aws/r/elasticache_subnet_group.html)
+* [Redshift Subnet Group](https://www.terraform.io/docs/providers/aws/r/redshift_subnet_group.html)
 * [DHCP Options Set](https://www.terraform.io/docs/providers/aws/r/vpc_dhcp_options.html)
 
 Usage

examples/complete-vpc/main.tf

@@ -10,6 +10,7 @@ module "vpc" {
   public_subnets      = ["10.10.11.0/24", "10.10.12.0/24", "10.10.13.0/24"]
   database_subnets    = ["10.10.21.0/24", "10.10.22.0/24", "10.10.23.0/24"]
   elasticache_subnets = ["10.10.31.0/24", "10.10.32.0/24", "10.10.33.0/24"]
+  redshift_subnets    = ["10.10.41.0/24", "10.10.42.0/24", "10.10.43.0/24"]
 
   create_database_subnet_group = false
 

examples/complete-vpc/outputs.tf

@@ -25,6 +25,11 @@ output "elasticache_subnets" {
   value       = ["${module.vpc.elasticache_subnets}"]
 }
 
+output "redshift_subnets" {
+  description = "List of IDs of redshift subnets"
+  value       = ["${module.vpc.redshift_subnets}"]
+}
+
 # NAT gateways
 output "nat_public_ips" {
   description = "List of public Elastic IPs created for AWS NAT Gateway"

main.tf

@@ -75,7 +75,7 @@ resource "aws_route" "public_internet_gateway" {
 # There are so many route-tables as the largest amount of subnets of each type (really?)
 #################
 resource "aws_route_table" "private" {
-  count = "${max(length(var.private_subnets), length(var.elasticache_subnets), length(var.database_subnets))}"
+  count = "${max(length(var.private_subnets), length(var.elasticache_subnets), length(var.database_subnets), length(var.redshift_subnets))}"
 
   vpc_id           = "${aws_vpc.this.id}"
   propagating_vgws = ["${var.private_propagating_vgws}"]
@@ -139,6 +139,29 @@ resource "aws_db_subnet_group" "database" {
   tags = "${merge(var.tags, map("Name", format("%s", var.name)))}"
 }
 
+##################
+# Redshift subnet
+##################
+resource "aws_subnet" "redshift" {
+  count = "${length(var.redshift_subnets)}"
+
+  vpc_id            = "${aws_vpc.this.id}"
+  cidr_block        = "${var.redshift_subnets[count.index]}"
+  availability_zone = "${element(var.azs, count.index)}"
+
+  tags = "${merge(var.tags, var.redshift_subnet_tags, map("Name", format("%s-redshift-%s", var.name, element(var.azs, count.index))))}"
+}
+
+resource "aws_redshift_subnet_group" "redshift" {
+  count = "${length(var.redshift_subnets) > 0 ? 1 : 0}"
+
+  name        = "${var.name}"
+  description = "Redshift subnet group for ${var.name}"
+  subnet_ids  = ["${aws_subnet.redshift.*.id}"]
+
+  tags = "${merge(var.tags, map("Name", format("%s", var.name)))}"
+}
+
 #####################
 # ElastiCache subnet
 #####################
@@ -277,6 +300,13 @@ resource "aws_route_table_association" "database" {
   route_table_id = "${element(aws_route_table.private.*.id, count.index)}"
 }
 
+resource "aws_route_table_association" "redshift" {
+  count = "${length(var.redshift_subnets)}"
+
+  subnet_id      = "${element(aws_subnet.redshift.*.id, count.index)}"
+  route_table_id = "${element(aws_route_table.private.*.id, count.index)}"
+}
+
 resource "aws_route_table_association" "elasticache" {
   count = "${length(var.elasticache_subnets)}"
 

outputs.tf

@@ -60,6 +60,21 @@ output "database_subnet_group" {
   value       = "${element(concat(aws_db_subnet_group.database.*.id, list("")), 0)}"
 }
 
+output "redshift_subnets" {
+  description = "List of IDs of redshift subnets"
+  value       = ["${aws_subnet.redshift.*.id}"]
+}
+
+output "redshift_subnets_cidr_blocks" {
+  description = "List of cidr_blocks of redshift subnets"
+  value       = ["${aws_subnet.redshift.*.cidr_block}"]
+}
+
+output "redshift_subnet_group" {
+  description = "ID of redshift subnet group"
+  value       = "${element(concat(aws_redshift_subnet_group.redshift.*.id, list("")), 0)}"
+}
+
 output "elasticache_subnets" {
   description = "List of IDs of elasticache subnets"
   value       = ["${aws_subnet.elasticache.*.id}"]
@@ -113,6 +128,11 @@ output "vpc_endpoint_s3_id" {
   value       = "${element(concat(aws_vpc_endpoint.s3.*.id, list("")), 0)}"
 }
 
+output "vpc_endpoint_s3_pl_id" {
+  description = "The prefix list for the S3 VPC endpoint."
+  value       = "${element(concat(aws_vpc_endpoint.s3.*.prefix_list_id, list("")), 0)}"
+}
+
 output "vpc_endpoint_dynamodb_id" {
   description = "The ID of VPC endpoint for DynamoDB"
   value       = "${element(concat(aws_vpc_endpoint.dynamodb.*.id, list("")), 0)}"
@@ -123,3 +143,8 @@ output "vgw_id" {
   description = "The ID of the VPN Gateway"
   value       = "${element(concat(aws_vpn_gateway.this.*.id, list("")), 0)}"
 }
+
+output "vpc_endpoint_dynamodb_pl_id" {
+  description = "The prefix list for the DynamoDB VPC endpoint."
+  value       = "${element(concat(aws_vpc_endpoint.dynamodb.*.prefix_list_id, list("")), 0)}"
+}

variables.tf

@@ -29,6 +29,12 @@ variable "database_subnets" {
   default     = []
 }
 
+variable "redshift_subnets" {
+  type        = "list"
+  description = "A list of redshift subnets"
+  default     = []
+}
+
 variable "elasticache_subnets" {
   type        = "list"
   description = "A list of elasticache subnets"
@@ -141,6 +147,11 @@ variable "database_subnet_tags" {
   default     = {}
 }
 
+variable "redshift_subnet_tags" {
+  description = "Additional tags for the redshift subnets"
+  default     = {}
+}
+
 variable "elasticache_subnet_tags" {
   description = "Additional tags for the elasticache subnets"
   default     = {}