Terraform conditional expressions

https://www.terraform.io/docs/language/expressions/conditionals.html

• condition ? true_val : false_val

• count = var.vpc_cidr_block != null ? 1 : 0

  retention_in_days = var.yourenv == "prod" ? 14 : 1

count             = var.validation_method != null ? 1 : 0

count = var.env == "prod" ? 1 : 0

https://www.hashicorp.com/blog/announcing-terraform-0-12

locals {
  public_instances_by_az = {
    for i in aws_instance.example : i.availability_zone => i...
    if i.associate_public_ip_address
  }
}

Related

• depends_on
• if
• Terraform meta argument: count
• Error: Unsupported attribute
• Terraform best practices

See also

• Terraform conditional expressions
• Terraform functions, Terraform collection functions: tolist, toset, length, sum, file, join, depends_on, zipmap, replace, lookup, read files, concat, merge, templatefile, for_each, format, element, slice, try, filebase64, upper, filemd5, coalesce, formatlist, flatten, sensitive, tonumber, jsondecode, yamldecode, pathexpand
• Terraform best practices, helpers/, prevent_destroy