Add map_public_ip_on_launch variable

[alexjurkiewicz]

what

• Support map_public_ip_on_launch for public subnets

why

• This is most useful when deploying public subnets with nat_enabled = false

[alexjurkiewicz]

Thanks for the advice about README updating. I've extended this variable to work for both public & private subnets. The use-cases for private subnets with public IPs are pretty niche (self-managed network gateways, other?) but they do exist, and it was a special case to not support this anyway.

[Gowiem]

/test all

[Gowiem]

@alexjurkiewicz Ah sorry to do it to you after already asking for changes, but can also ask you to add separate variables for private vs public subnets? I worry that if folks go to enable this, they won't expect it to take effect on their private subnets, which could in turn create a security issue for them.

[alexjurkiewicz]

Since this module can only create public or private subnets (not both at the same time), what sort of scenario are you thinking of where people could enable this accidentally on private subnets?

I'm guessing you're thinking of some scenario with for_each. But it doesn't seem to be that tricky of a thing to deal with:

module "subnets" {
  for_each = toset(["public", "private"])
  source                  = "git::https://github.com/cloudposse/terraform-aws-named-subnets.git?ref=master"
  # other params skipped
  type                    = each.key
  map_public_ip_on_launch = each.key == "public"
}

You would be performing similar logic for other params like igw_id/ngw_id, cidr_block, etc.

[Gowiem]

@alexjurkiewicz Solid point! I haven't used this module personally (I typically use terraform-aws-dynamic-subnets), so I didn't know that it was meant to create one set of subnet type or another.

[Gowiem]

@alexjurkiewicz
Thanks for the contribution! Released as 0.8.0.