v0.70.0-beta2024120501

[yhakbar]

Deprecation Notice

This release deprecates terragrunt.hcl as the idiomatic root of Terragrunt configurations.

Naming the file placed at the root of Terragrunt configurations terragrunt.hcl is a pattern that does not provide any functional advantage over calling it anything else (e.g. root.hcl), but does serve to provide additional confusion and risk to Terragrunt users, as they can easily use Terragrunt in such a way that it ends up treating the terragrunt.hcl file at the root as a unit instead of shared configuration.

This pattern is very longstanding in typical Terragrunt usage, so changing it can be difficult. To get the ball rolling on this, the behavior will be deprecated, but still supported for the near future (and for a pretty long time thereafter).

How this will be achieved

Terragrunt will now emit warnings whenever it detects that users are following a pattern indicating usage of a root terragrunt.hcl file.

The warning will look like this:

16:04:54.555 WARN   Using `terragrunt.hcl` as the root of Terragrunt configurations is an anti-pattern, and no longer recommended. In a future version of Terragrunt, this will result in an error. You are advised to use a differently named file like `root.hcl` instead. For more information, see https://terragrunt.gruntwork.io/docs/migrate/migrating-from-root-terragrunt-hcl

You can take a look at what those docs will look like here.

Those docs include information on a new Strict Control named root-terragrunt-hcl that will allow users to opt-in for a breaking change preventing usage of a root terragrunt.hcl.

Using this strict control will also update defaults for commands like scaffold and catalog so that they don't assume usage of a root terragrunt.hcl file.

Feedback Requested

You are encouraged to share your feedback on this pre-released change. You can either share your feedback via the associated GitHub Discussion, or you can share your feedback in our Discord.

Full Changelog: v0.69.7...v0.70.0-beta2024120501

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This discussion was created from the release v0.70.0-beta2024120501.

[keiransteele-phocas]

Hi, could find_in_parent_folders() not also be changed to look for "root.hcl" as well to ease the migration?

[yhakbar]

Hey @keiransteele-phocas ,

We were discussing this internally. The issue that I have with this, personally, is that I don't think it actually helps anyone.

We are still going to support having a terragrunt.hcl file as the root of Terragrunt configurations for a long time. We are merely going to be warning users that they should explicitly indicate where they are trying to include configurations from.

I personally don't think seeing this in terragrunt.hcl files is a good experience for new users, but I would love feedback on that:

include "root" {
  path = find_in_parent_folders()
}

I know that when I first saw that (and frequently when I first show it to other users), I was confused as to what find_in_parent_folders was doing. I think it's clearer when indicating the name of the file that's being found:

include "root" {
  path = find_in_parent_folders("root.hcl")
}

At the end of the day, there's nothing special about the "root" Terragrunt configuration. It's just another configuration being included that could be called whatever a user wants.