Chapter 5: Terraform tips and tricks

• usage:

  resource "blablabla" "blablabla_name" {
  count = 3
  name  = "bla${count.index}"
  }

• result: 3 elements ([0],[1],[2]) → resources array
• with length():

  variable "bla_names" {
    type    = list(string)
    default = ["bla_green","bla_yellow","bla_red"] 
  }
  resource "blablabla" "blablabla_name" {
    count = length(var.bla_names)
    name  = bla_names[count.index]
  }

• output
  • [#]: use cardinal to access a concrete element
  • [*]: all elements from resource list
• each element is assigned to their index in state, deletes o modifications implies «move» all elements after that.
• only usable for resources, no inline blocks

• lists (using toset() function), sets and maps
• for use in resources o inline blocks
• use each.key and each.value
• usage:

  variable "bla_names" {
    type    = list(string)
    default = ["bla_green","bla_yellow","bla_red"] 
  }
  resource "blablabla" "blablabla_name" {
  for_each = toset(var.bla_names)
  name  = each.value
  }

variable "bla_names" {
  type    = map(string)
  default = {"green" = "bla_green","yellow" = "bla_yellow","red" = "bla_red"}
  #default = map("green","bla_green", "yellow","bla_yellow", "red","bla_red")
}
resource "blablabla" "blablabla_name" {
for_each = toset(var.bla_names)
name  = each.value
}

• output:
  • values(<resource_name>)[*].attribute

variable "booleana" {
  type = bool
}
resource "resource" "resource_name" {
  count = var.booleana ? 1 : 0
  ...
}
variable "cadena" {
  type = string
  default = "aaa"
}
resource "resource" "resource_name {
  count = format("%.1s",var.cadena) == "a" ? 1 : 0
}