Use 'required_providers' for AWS provider minimum version

[MarcMeszaros]

The way the AWS provider minimum version was specified was causing version conflicts in my Terraform project. It is also using the deprecated method of declaring provider versions.

https://www.terraform.io/docs/language/providers/configuration.html#version-an-older-way-to-manage-provider-versions

The other change is the removal of the S3 backend and terraform config block. Since this is a public module consumed by other terraform workspaces, terraform ignores the S3 backend. In my particular case I don't use S3 for state management and use a different backend.

[vainkop]

@MarcMeszaros as you can see my configuration is using Terragrunt with an s3 backend which is the most popular & recommended way of managing the Terraform state so please put it back into tf code.

I suggest you use the following format for the versions.tf & also it's safe to bump up the TF version to 0.14.10:

terraform {
  backend "s3" {}
}

provider "aws" {
  region = var.region
}

terraform {
  required_version = ">= 0.14.10"

  required_providers {
    aws = {
      source  = "hashicorp/aws"
      version = "~> 3.0"
    }
    tls = {
      source  = "hashicorp/tls"
      version = "~> 3.0"
    }
    archive = {
      source  = "hashicorp/archive"
      version = "~> 2.1"
    }
    null = {
      source  = "hashicorp/null"
      version = "~> 3.0"
    }
    local = {
      source  = "hashicorp/local"
      version = "~> 2.1"
    }
  }
}

[MarcMeszaros]

@vainkop Added back the S3 backend for terragrunt users and refactored to have the versions.tf as suggested. I also ran terraform fmt on the module.

I had originally removed the backend because of this warning (terraform v0.15.3) during plan:

We use terraform cloud and we don't use terragrunt. We originally found this module via the terraform module registry. Is there a way to have defaults for terragrunt users without also throwing the warning for non terragrunt users using the module?

[vainkop]

@vainkop Added back the S3 backend for terragrunt users and refactored to have the versions.tf as suggested. I also ran terraform fmt on the module.

@MarcMeszaros I didn't mean to add all those providers into configuration, I just gave an example :) Please remove the ones which are not actually used. Thanks

[vainkop]

We use terraform cloud and we don't use terragrunt. We originally found this module via the terraform module registry. Is there a way to have defaults for terragrunt users without also throwing the warning for non terragrunt users using the module?

A terragrunt.hcl similar to the following is usually used by terragrunt users for configuration of the backend: https://github.com/vainkop/terraform-aws-wireguard/blob/master/example/terragrunt.hcl#L4

A warning is not an error so shouldn't be a problem but it's not ideal I agree.

It's possible to use terragrunt with terraform cloud but the experience is limited:

https://stackoverflow.com/a/60066545/7778447

https://blog.gruntwork.io/how-deploy-production-grade-infrastructure-using-gruntwork-with-terraform-cloud-aca919ca92c2

https://gruntwork.io/guides/foundations/how-to-use-gruntwork-infrastructure-as-code-library#integration_with_tfc_tfe

[MarcMeszaros]

@vainkop my mistake. I thought you literally wanted all the other dependencies in the versions.tf. 😉

I also merged the s3 backend in the same terraform declaration in versions.tf.

I move the provider aws { } to versions.tf since it seems more related to module setup than the actual module implementation in main.tf. Let me know if you actually want the aws provider declaration inside main.tf.