Virtual Geek

Below are the few examples of Terraform on to converting single string to array of list or set. This code I was wanted in my one of my Azure automation task. In this example I have defined a variable justice_leage with same default value..

For conversion, In the first scenario I can use split() function to create list. In the second option is to put variable inside toset([]). Lastly you can use simple square bracket [ ]. There are other some of examples for map as well shown to convert keys or values to convert to list in the below code.

variable "justice_leage" {
  type = string
  default = "justice_league"
}

output "superman" {
  value = split(",", var.justice_leage)
}

output "wonder_woman" {
  value = toset([var.justice_leage])
}

output "dc_to_object_or_string" {
  value = jsonencode(var.justice_leage)
}

#######################

variable "avenger" {
  type = map(string)
  default = {
    "Bruce_Banner" = "Hulk"
    "Wanda_Maximoff" = "Scarlet_Witch"
  }
}

output "avengers_to_list" {
  value = values(var.avenger)
}

output "avengers_to_set" {
  value = toset(values(var.avenger))
}

output "avengers_map_to_object_or_string" {
  value = jsonencode(var.avenger)
}

Download Terraform_convert_string_to_map_list.tf here or it is also available on github.com.

Below is the output of the result output after applying terraform configuration.

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terraform apply --auto-approve  

Changes to Outputs:
  + avengers_map_to_object_or_string = jsonencode(
        {
          + Bruce_Banner   = "Hulk"
          + Wanda_Maximoff = "Scarlet_Witch"
        }
    )
  + avengers_to_list                 = [
      + "Hulk",
      + "Scarlet_Witch",
    ]
  + avengers_to_set                  = [
      + "Hulk",
      + "Scarlet_Witch",
    ]
  + dc_to_object_or_string           = "\"justice_league\""
  + superman                         = [
      + "justice_league",
    ]
  + wonder_woman                     = [
      + "justice_league",
    ]

You can apply this plan to save these new output values to the Terraform state, without changing any real infrastructure.

Apply complete! Resources: 0 added, 0 changed, 0 destroyed.

Outputs:

avengers_map_to_object_or_string = "{\"Bruce_Banner\":\"Hulk\",\"Wanda_Maximoff\":\"Scarlet_Witch\"}"
avengers_to_list = tolist([
  "Hulk",
  "Scarlet_Witch",
])
avengers_to_set = toset([
  "Hulk",
  "Scarlet_Witch",
])
dc_to_object_or_string = "\"justice_league\""
superman = tolist([
  "justice_league",
])
wonder_woman = toset([
  "justice_league",
])

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