Terraform variable files

Question

I am trying to use a variables file to deploy resource groups in Azure using Terraform but it works if I only have one variable. If I use two I get an error:

"invalid value "variables.tf" for flag -var-file: multiple map declarations not supported for variables"

The variables file is as below :

variable "resource_group_name" {
  description = "The name of the resource group in which the resources will be created"
  default     = "im-from-the-variables-file"
}

variable "location" {
  description = "The location/region where the virtual network is created. Changing this forces a new resource to be created."
  default     = "west europe"
}

The main file used to deploy is as below:

resource "azurerm_resource_group" "vm" {
  name     = "${var.resource_group_name}"
  location = "${var.location}"
}

What does your tfvars file look like that you are passing with -var-file? — ydaetskcoR
it the first block of code : variable "resource_group_name" { description = "The name of the resource group in which the resources will be created" default = "im-from-the-variables-file" } variable "location" { description = "The location/region where the virtual network is created. Changing this forces a new resource to be created." default = "west europe" } — itye1970

ydaetskcoR ydaetskcoR · Accepted Answer · 2018-06-14T12:13:53

You've confused the variable definition syntax to the variable setting syntax.

Terraform will concatenate all the .tf files in a directory so your variables.tf file (assuming it's in the same directory as your main.tf (or whatever contains your azurerm_resource_group resources etc) is already included.

You need to define every variable before it can be used so things like:

resource "azurerm_resource_group" "vm" {
  name     = "${var.resource_group_name}"
  location = "${var.location}"
}

by themselves would not be valid as the variables resource_group_name and location are not defined.

You define variables with the syntax you've used in your variables.tf file:

variable "location" {
  description = "The location/region where the virtual network is created. Changing this forces a new resource to be created."
  default     = "west europe"
}

To override the defaults (if wanted or if a default isn't provided) then you need to either pass the variable in at run time (using TF_VAR_location environment variables or by using -var location="west us") or you can define vars files that take the form:

location = "west us"
resource_group_name = "im-from-the-variables-file"

Terraform will automatically load any files in the directory called terraform.tfvars or *.auto.tfvars and you can also define extra vars files at any point by using -var-file=myvars.tfvars as you have attempted to do (but with a .tf file containing HCL instead of key-pairs.

Terraform variable files

2 Answers