Unable to use Dockerfile variable path in module

[dextermb]

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Terraform (and docker Provider) Version

~/projects/terraform main* ❯ terraform -v
Terraform v1.9.5
on darwin_arm64

Your version of Terraform is out of date! The latest version
is 1.9.7. You can update by downloading from https://www.terraform.io/downloads.html

terraform {
  required_providers {
    docker = {
      source  = "kreuzwerker/docker"
      version = "~> 3.0.1"
    }
  }
}

Terraform Configuration Files

Website Module

resource "docker_image" "alpine" {
  name         = "alpine"
  keep_locally = false

  build {
    dockerfile = var.dockerfile
    context    = var.dockerfile_context
  }
}

Main Terraform

module "website" {
  source = "../modules/website"

  network_id    = docker_network.network.id
  prefix        = var.prefix
  external_port = var.external_port

  dockerfile         = "${path.cwd}/Dockerfile"
  dockerfile_context = "${path.cwd}/../.."

  mount_source = null
}

Debug Output

Gist

Expected Behaviour

I should be able to reference a Dockerfile from any given directory within my module through variables.

Actual Behaviour

For some reason Terraform (or Docker provider) is unable to find the Dockerfile through an absolute path even though I can use cat on the generated output and have it output the contents of the file.

I have attempted to do relative paths but I still run into the same issue.

Steps to Reproduce

1. Create a module which has a docker_image resource and a build.dockerfile value from a variable.
2. Use module in parent script, provide variables
3. See error

Important Factoids

tree output

~/projects/next/home/terraform main* ❯ tree -L 3
.
├── development
│   ├── Dockerfile
│   ├── main.tf
│   └── variables.tf
├── modules
│   ├── database
│   │   ├── main.tf
│   │   ├── outputs.tf
│   │   └── variables.tf
│   └── website
│       ├── main.tf
│       ├── outputs.tf
│       └── variables.tf
└── production
    ├── Dockerfile
    ├── main.tf
    ├── terraform.tfstate
    ├── terraform.tfstate.backup
    └── variables.tf

6 directories, 14 files