How to conditionally create a resource with Terraform

There might be situations where you would like to create a resource conditionally if it does not exist. For that particular case, you can use count property.

resource "aws_route53_zone" "primary" {  
  count = var.create_dns_zone ? 1 : 0  
  name  = var.domain  
}  
  
data "aws_route53_zone" "primary" {  
  count = var.create_dns_zone ? 0 : 1  
  name  = var.domain  
}  
  
locals {  
  dns_zone_id = var.create_dns_zone ? aws_route53_zone.primary[0].name : data.aws_route53_zone.primary[0].zone_id  
  subdomain   = var.environment_name == "prod" ? "" : "${var.environment_name}."  
}  

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