Terraform variables not applied from command line

Question

I've the file structure below, terraform CLI is not using the runtime variable value in S3 file's content. It's always defaulting to 0 value.

Structure:

terraform
    main.tf
    api/
        variables.tf
        s3.tf

main.tf

module "api" {
  source = "./api"

  providers = {
    aws = "aws.us-east-1"
  }
}

variables.tf

variable "build-number" {
  description = "jenkins build number"
  type        = "string"
  default = "0"
}

s3.tf

resource "aws_s3_bucket_object" "api-build-version" {
  bucket = "api-code"
  key    = "build-version"
  content = "${var.build-number}"
  etag = "${md5("${var.build-number}")}"
}

terraform plan -var "build-number=2" -target aws_s3_bucket_object.api-build-version

My Terraform version is v0.11.8

Helder Sepulveda Helder Sepulveda · Accepted Answer · 2020-06-04T01:51:10

In your structure, your variable is only under the API module

    terraform
        main.tf
        api/
            variables.tf
            s3.tf

You need that same variable at the root, add it to the main.tf or own file and then pass it on like this:

module "api" {
  source = "./api"

  build-number = "${var.build-number}"

  providers = {
    aws = "aws.us-east-1"
  }
}

All the sub-folders are modules in terraform, variables are not global... you do to declare variables on every level, and if they are identical you can do a symlink to one file to reduce copy-paste.

If it was just a flat structure you would not need that,
try this if you want:

variable "build-number" {
  type    = "string"
  default = "0"
}

output "test" {
  value = "${var.build-number}"
}

terraform apply -var "build-number=2"

That outputs the correct variable value

Terraform variables not applied from command line

1 Answers