How can I iterate through a map variable in terraform

Question

Im trying to iterate through a variable type map and i'm not sure how to

This is what i have so far

In my main.tf:

resource "aws_route_53_record" "proxy_dns" {
  count = "${length(var.account_name)}"
  zone_id = "${infrastructure.zone_id}"
  name = "proxy-${element(split(",", var.account_name), count.index)}-dns
  type = CNAME
  ttl = 60
  records = ["{records.dns_name}"]
}

And in my variables.tf

variable "account_name" {
  type = "map"
  default = {
    "account1" = "accountA"
    "account2" = "accountB"
  }
}

I want to be able to create multiple resources with the different account names

Answer 1

If you are using Terraform 0.12.6 or later then you can use for_each instead of count to produce one instance for each element in your map:

resource "aws_route53_record" "proxy_dns" {
  for_each = var.account_name

  zone_id = infrastructure.zone_id
  name    = "proxy-${each.value}-dns"
  # ... etc ...
}

The primary advantage of for_each over count is that Terraform will identify the instances by the key in the map, so you'll get instances like aws_route53_record.proxy_dns["account1"] instead of aws_route53_record.proxy_dns[0], and so you can add and remove elements from your map in future with Terraform knowing which specific instance belongs to each element.

each.key and each.value in the resource type arguments replace count.index when for_each is used. They evaluate to the key and value of the current map element, respectively.