Update vpc region in route 53 zone association

[yuan-stripe]

Changes proposed in this pull request:

• Update vpc region in route 53 zone association

Output from acceptance testing (too afraid to run on our internal infrastructure)

All unit tests passed though:

$ make test
==> Checking that code complies with gofmt requirements...
go test ./... -timeout=30s -parallel=4
?   	github.com/terraform-providers/terraform-provider-aws	[no test files]
ok  	github.com/terraform-providers/terraform-provider-aws/aws	1.807s

This addresses a bug when new VPCs are inserted into the associated VPC list of a route 53 zone.

The Setup

• A Route 53 zone which have 2+ VPCs associated
• Then a new VPC is inserted into the list of associated VPCs

Module "zone"

# Input
variable "name" {
  description = "The name of the internal zone"
}

variable "associated_vpc_ids" {
  description = "The list of VPC IDs to associate with this zone"
  type        = "list"
}

variable "associated_vpc_regions" {
  description = "The list of VPC regions for the aforementioned VPC IDs"
  type        = "list"
}

# Resources
resource "aws_route53_zone" "primary" {
  name       = "${var.name}"
  comment    = "${var.comment}"
  vpc_id     = "${var.associated_vpc_ids[0]}"
  vpc_region = "${var.associated_vpc_regions[0]}"
}

resource "aws_route53_zone_association" "additional" {
  count      = "${length(var.associated_vpc_ids) - 1}"
  zone_id    = "${aws_route53_zone.primary.zone_id}"
  vpc_id     = "${element(var.associated_vpc_ids, count.index + 1)}"
  vpc_region = "${element(var.associated_vpc_regions, count.index + 1)}"
}

Zone "Foo" - Version 1

module "zone-foo" {
  source = "zone"

  name                   = "foo.com."
  associated_vpc_ids     = ["vpc1", "vpc2"]
  associated_vpc_regions = "["us-west-1", "us-east-1"]
}

Zone "Foo" - Version 2

module "zone-foo" {
  source = "zone"

  name                   = "foo.com."
  associated_vpc_ids     = ["vpc1", "vpc-new", "vpc2"]
  associated_vpc_regions = "["us-west-1", "us-west-2", "us-east-1"]
}

The Problem

After version 2 is applied, the terraform state does have vpc-new, but its vpc region is us-east-1, instead of us-west-2, because terraform thinks the second associated VPC has changed from vpc2 to vpc-new, but it does not update vpc region in this update.

[bflad]

Hi @yuan-stripe 👋 Thanks for submitting this and sorry for the delay in review. It turns out this was handled by a larger refactoring of the aws_route53_zone resource to support multiple VPC associations, which will be supported in version 1.42.0 of the AWS provider. As for the aws_route53_zone_association resource, it will be receiving its own refactoring very shortly to use some of the simpler code just introduced and fix some other bugs in the same process.

[ghost]

I'm going to lock this issue because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active issues.

If you feel this issue should be reopened, we encourage creating a new issue linking back to this one for added context. Thanks!