Merge pull request #87 from silinternational/develop

Release 8.6.0 - Configurable VPC CIDR blocks

aws/vpc/README.md

@@ -20,12 +20,15 @@ be useful.
 
  - `enable_dns_hostnames` - default `false`
  - `create_nat_gateway` - default `true`
+ - `private_subnet_cidr_blocks`
+ - `public_subnet_cidr_blocks`
+ - `vpc_cidr_block`
 
 ## Outputs
 
  - `vpc_default_sg_id` - The VPC default security group ID
  - `public_subnet_ids` - A list of the public subnet IDs
- - `public_subnet_cidr_blocks` - A list of public subnet CIDR blocks, ex: `["10.0.10.0/24","10.0.12.0/24"]`
+ - `public_subnet_cidr_blocks` - A list of public subnet CIDR blocks, ex: `["10.0.10.0/24","10.0.20.0/24"]`
  - `private_subnet_ids` - A list of the private subnet IDs
  - `private_subnet_cidr_blocks` - A list of private subnet CIDR blocks, ex: `["10.0.11.0/24","10.0.22.0/24"]`
  - `db_subnet_group_name` - The name of the DB subnet group

aws/vpc/main.tf

@@ -2,7 +2,7 @@
  * Create VPC using app name and env to name it
  */
 resource "aws_vpc" "vpc" {
-  cidr_block           = "10.0.0.0/16"
+  cidr_block           = var.vpc_cidr_block
   enable_dns_hostnames = var.enable_dns_hostnames
 
   tags = {
@@ -27,7 +27,7 @@ resource "aws_subnet" "public_subnet" {
   count             = length(var.aws_zones)
   vpc_id            = aws_vpc.vpc.id
   availability_zone = element(var.aws_zones, count.index)
-  cidr_block        = "10.0.${(count.index + 1) * 10}.0/24"
+  cidr_block        = element(var.public_subnet_cidr_blocks, count.index)
 
   tags = {
     Name     = "public-${element(var.aws_zones, count.index)}"
@@ -40,7 +40,7 @@ resource "aws_subnet" "private_subnet" {
   count             = length(var.aws_zones)
   vpc_id            = aws_vpc.vpc.id
   availability_zone = element(var.aws_zones, count.index)
-  cidr_block        = "10.0.${(count.index + 1) * 11}.0/24"
+  cidr_block        = element(var.private_subnet_cidr_blocks, count.index)
 
   tags = {
     Name     = "private-${element(var.aws_zones, count.index)}"

aws/vpc/vars.tf

@@ -31,3 +31,21 @@ variable "create_nat_gateway" {
   type        = bool
   default     = true
 }
+
+variable "private_subnet_cidr_blocks" {
+  description = "The CIDR blocks for the private subnets (one per AZ, in order). There must be at least as many private CIDRs as AZs, and they must not overlap the public CIDRs."
+  type        = list(string)
+  default     = ["10.0.11.0/24", "10.0.22.0/24", "10.0.33.0/24", "10.0.44.0/24"]
+}
+
+variable "public_subnet_cidr_blocks" {
+  description = "The CIDR blocks for the public subnets (one per AZ, in order). There must be at least as many public CIDRs as AZs, and they must not overlap the private CIDRs."
+  type        = list(string)
+  default     = ["10.0.10.0/24", "10.0.20.0/24", "10.0.30.0/24", "10.0.40.0/24"]
+}
+
+variable "vpc_cidr_block" {
+  description = "The block of IP addresses (as a CIDR) the VPC should use"
+  type        = string
+  default     = "10.0.0.0/16"
+}