feat: Allow creating VPC routes for already existing or shared TGW (#114)

kamilhristov · bryantbiggs · web-flow · commit 20c4dc4f698b · 2023-12-11T08:44:15.000-05:00
Co-authored-by: Bryant Biggs &lt;bryantbiggs@gmail.com&gt;
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
@@ -1,6 +1,6 @@
 repos:
   - repo: https://github.com/antonbabenko/pre-commit-terraform
-    rev: v1.77.0
+    rev: v1.83.6
     hooks:
       - id: terraform_fmt
       - id: terraform_validate
@@ -23,7 +23,7 @@ repos:
           - '--args=--only=terraform_standard_module_structure'
           - '--args=--only=terraform_workspace_remote'
   - repo: https://github.com/pre-commit/pre-commit-hooks
-    rev: v4.4.0
+    rev: v4.5.0
     hooks:
       - id: check-merge-conflict
       - id: end-of-file-fixer
diff --git a/README.md b/README.md
@@ -104,6 +104,7 @@ No modules.
 |------|-------------|------|---------|:--------:|
 | <a name="input_amazon_side_asn"></a> [amazon\_side\_asn](#input\_amazon\_side\_asn) | The Autonomous System Number (ASN) for the Amazon side of the gateway. By default the TGW is created with the current default Amazon ASN. | `string` | `null` | no |
 | <a name="input_create_tgw"></a> [create\_tgw](#input\_create\_tgw) | Controls if TGW should be created (it affects almost all resources) | `bool` | `true` | no |
+| <a name="input_create_tgw_routes"></a> [create\_tgw\_routes](#input\_create\_tgw\_routes) | Controls if TGW Route Table / Routes should be created | `bool` | `true` | no |
 | <a name="input_description"></a> [description](#input\_description) | Description of the EC2 Transit Gateway | `string` | `null` | no |
 | <a name="input_enable_auto_accept_shared_attachments"></a> [enable\_auto\_accept\_shared\_attachments](#input\_enable\_auto\_accept\_shared\_attachments) | Whether resource attachment requests are automatically accepted | `bool` | `false` | no |
 | <a name="input_enable_default_route_table_association"></a> [enable\_default\_route\_table\_association](#input\_enable\_default\_route\_table\_association) | Whether resource attachments are automatically associated with the default association route table | `bool` | `true` | no |
@@ -125,7 +126,6 @@ No modules.
 | <a name="input_tgw_vpc_attachment_tags"></a> [tgw\_vpc\_attachment\_tags](#input\_tgw\_vpc\_attachment\_tags) | Additional tags for VPC attachments | `map(string)` | `{}` | no |
 | <a name="input_timeouts"></a> [timeouts](#input\_timeouts) | Create, update, and delete timeout configurations for the transit gateway | `map(string)` | `{}` | no |
 | <a name="input_transit_gateway_cidr_blocks"></a> [transit\_gateway\_cidr\_blocks](#input\_transit\_gateway\_cidr\_blocks) | One or more IPv4 or IPv6 CIDR blocks for the transit gateway. Must be a size /24 CIDR block or larger for IPv4, or a size /64 CIDR block or larger for IPv6 | `list(string)` | `[]` | no |
-| <a name="input_create_tgw_routes"></a> [create\_tgw\_routes](#input\_create\_tgw\_routes) | Controls if TGW Route Table / Routes should be created | `bool` | `true` | no |
 | <a name="input_transit_gateway_route_table_id"></a> [transit\_gateway\_route\_table\_id](#input\_transit\_gateway\_route\_table\_id) | Identifier of EC2 Transit Gateway Route Table to use with the Target Gateway when reusing it between multiple TGWs | `string` | `null` | no |
 | <a name="input_vpc_attachments"></a> [vpc\_attachments](#input\_vpc\_attachments) | Maps of maps of VPC details to attach to TGW. Type 'any' to disable type validation by Terraform. | `any` | `{}` | no |
 
diff --git a/examples/complete/README.md b/examples/complete/README.md
@@ -19,7 +19,7 @@ Note that this example may create resources which cost money. Run `terraform des
 
 | Name | Version |
 |------|---------|
-| <a name="requirement_terraform"></a> [terraform](#requirement\_terraform) | >= 0.13.1 |
+| <a name="requirement_terraform"></a> [terraform](#requirement\_terraform) | >= 1.0 |
 | <a name="requirement_aws"></a> [aws](#requirement\_aws) | >= 4.4 |
 
 ## Providers
@@ -31,8 +31,8 @@ No providers.
 | Name | Source | Version |
 |------|--------|---------|
 | <a name="module_tgw"></a> [tgw](#module\_tgw) | ../../ | n/a |
-| <a name="module_vpc1"></a> [vpc1](#module\_vpc1) | terraform-aws-modules/vpc/aws | ~> 3.0 |
-| <a name="module_vpc2"></a> [vpc2](#module\_vpc2) | terraform-aws-modules/vpc/aws | ~> 3.0 |
+| <a name="module_vpc1"></a> [vpc1](#module\_vpc1) | terraform-aws-modules/vpc/aws | ~> 5.0 |
+| <a name="module_vpc2"></a> [vpc2](#module\_vpc2) | terraform-aws-modules/vpc/aws | ~> 5.0 |
 
 ## Resources
 
diff --git a/examples/complete/main.tf b/examples/complete/main.tf
@@ -83,7 +83,7 @@ module "tgw" {
 
 module "vpc1" {
   source  = "terraform-aws-modules/vpc/aws"
-  version = "~> 3.0"
+  version = "~> 5.0"
 
   name = "${local.name}-vpc1"
   cidr = "10.10.0.0/16"
@@ -100,7 +100,7 @@ module "vpc1" {
 
 module "vpc2" {
   source  = "terraform-aws-modules/vpc/aws"
-  version = "~> 3.0"
+  version = "~> 5.0"
 
   name = "${local.name}-vpc2"
   cidr = "10.20.0.0/16"
diff --git a/examples/complete/versions.tf b/examples/complete/versions.tf
@@ -1,5 +1,5 @@
 terraform {
-  required_version = ">= 0.13.1"
+  required_version = ">= 1.0"
 
   required_providers {
     aws = {
diff --git a/examples/multi-account/README.md b/examples/multi-account/README.md
@@ -19,7 +19,7 @@ Note that this example may create resources which cost money. Run `terraform des
 
 | Name | Version |
 |------|---------|
-| <a name="requirement_terraform"></a> [terraform](#requirement\_terraform) | >= 0.13.1 |
+| <a name="requirement_terraform"></a> [terraform](#requirement\_terraform) | >= 1.0 |
 | <a name="requirement_aws"></a> [aws](#requirement\_aws) | >= 4.4 |
 
 ## Providers
@@ -32,8 +32,8 @@ No providers.
 |------|--------|---------|
 | <a name="module_tgw"></a> [tgw](#module\_tgw) | ../../ | n/a |
 | <a name="module_tgw_peer"></a> [tgw\_peer](#module\_tgw\_peer) | ../../ | n/a |
-| <a name="module_vpc1"></a> [vpc1](#module\_vpc1) | terraform-aws-modules/vpc/aws | ~> 3.0 |
-| <a name="module_vpc2"></a> [vpc2](#module\_vpc2) | terraform-aws-modules/vpc/aws | ~> 3.0 |
+| <a name="module_vpc1"></a> [vpc1](#module\_vpc1) | terraform-aws-modules/vpc/aws | ~> 5.0 |
+| <a name="module_vpc2"></a> [vpc2](#module\_vpc2) | terraform-aws-modules/vpc/aws | ~> 5.0 |
 
 ## Resources
 
diff --git a/examples/multi-account/main.tf b/examples/multi-account/main.tf
@@ -104,6 +104,9 @@ module "tgw_peer" {
       transit_gateway_default_route_table_association = false
       transit_gateway_default_route_table_propagation = false
 
+      vpc_route_table_ids  = module.vpc1.private_route_table_ids
+      tgw_destination_cidr = "0.0.0.0/0"
+
       tgw_routes = [
         {
           destination_cidr_block = "30.0.0.0/16"
@@ -128,7 +131,7 @@ module "tgw_peer" {
 
 module "vpc1" {
   source  = "terraform-aws-modules/vpc/aws"
-  version = "~> 3.0"
+  version = "~> 5.0"
 
   name = "${local.name}-vpc1"
   cidr = "10.10.0.0/16"
@@ -146,7 +149,7 @@ module "vpc1" {
 
 module "vpc2" {
   source  = "terraform-aws-modules/vpc/aws"
-  version = "~> 3.0"
+  version = "~> 5.0"
 
   providers = {
     aws = aws.peer
diff --git a/examples/multi-account/versions.tf b/examples/multi-account/versions.tf
@@ -1,5 +1,5 @@
 terraform {
-  required_version = ">= 0.13.1"
+  required_version = ">= 1.0"
 
   required_providers {
     aws = {
diff --git a/main.tf b/main.tf
@@ -15,6 +15,7 @@ locals {
       for rtb_id in try(v.vpc_route_table_ids, []) : {
         rtb_id = rtb_id
         cidr   = v.tgw_destination_cidr
+        tgw_id = var.create_tgw ? aws_ec2_transit_gateway.this[0].id : v.tgw_id
       }
     ]
   ])
@@ -110,11 +111,14 @@ resource "aws_ec2_transit_gateway_route" "this" {
 }
 
 resource "aws_route" "this" {
-  for_each = { for x in local.vpc_route_table_destination_cidr : x.rtb_id => x.cidr }
+  for_each = { for x in local.vpc_route_table_destination_cidr : x.rtb_id => {
+    cidr   = x.cidr,
+    tgw_id = x.tgw_id
+  } }
 
   route_table_id         = each.key
-  destination_cidr_block = each.value
-  transit_gateway_id     = aws_ec2_transit_gateway.this[0].id
+  destination_cidr_block = each.value["cidr"]
+  transit_gateway_id     = each.value["tgw_id"]
 }
 
 resource "aws_ec2_transit_gateway_route_table_association" "this" {

Original file line number	Diff line number	Diff line change
`@@ -15,6 +15,7 @@ locals {`
`15`	`15`	`for rtb_id in try(v.vpc_route_table_ids, []) : {`
`16`	`16`	`rtb_id = rtb_id`
`17`	`17`	`cidr = v.tgw_destination_cidr`
	`18`	`+ tgw_id = var.create_tgw ? aws_ec2_transit_gateway.this[0].id : v.tgw_id`
`18`	`19`	`}`
`19`	`20`	`]`
`20`	`21`	`])`
`@@ -110,11 +111,14 @@ resource "aws_ec2_transit_gateway_route" "this" {`
`110`	`111`	`}`
`111`	`112`
`112`	`113`	`resource "aws_route" "this" {`
`113`		`- for_each = { for x in local.vpc_route_table_destination_cidr : x.rtb_id => x.cidr }`
	`114`	`+ for_each = { for x in local.vpc_route_table_destination_cidr : x.rtb_id => {`
	`115`	`+ cidr = x.cidr,`
	`116`	`+ tgw_id = x.tgw_id`
	`117`	`+ } }`
`114`	`118`
`115`	`119`	`route_table_id = each.key`
`116`		`- destination_cidr_block = each.value`
`117`		`- transit_gateway_id = aws_ec2_transit_gateway.this[0].id`
	`120`	`+ destination_cidr_block = each.value["cidr"]`
	`121`	`+ transit_gateway_id = each.value["tgw_id"]`
`118`	`122`	`}`
`119`	`123`
`120`	`124`	`resource "aws_ec2_transit_gateway_route_table_association" "this" {`