Terragrunt Imports Roadmap

[bakavets]

Hi there! Hope you are doing well!

Could you share any information about imports?

Ref: Implement imports RFC

Is there any ETA for that feature?

Thanks for your reply in advance!

[josh-padnick]

Hello! FYI, the best person to answer this is @yhakbar, however he's OOO until next week. We'll post back then!

[yhakbar]

Hey @bakavets ,

I wasn't here when the initial imports RFC was proposed, but I've read through it.

To be honest, I'm not sure we should invest time in developing this feature, or that it's necessary. The fact that Terragrunt configurations can't be merged through chained configuration includes right now results in configurations that are easier to read.

e.g.

In the scenario where you have the following imports:
A <-- B <-- C
A' <-- B <-- C

Where C depends on B, and B depends on both A and A', you have four different configurations you have to read to know what's going on in C, and two of them aren't even referenced in the C file. This feels to me like the kind of abstraction that makes Terragrunt harder to use, and it doesn't provide any functional advantage, as far as I can tell. If someone was to instead structure their configurations like this:

B <-- C
A <-- C
A' <-- C

You still have to read four configurations, but you can now read C alone and know everywhere that configurations could be relevant to C. This is especially important in CI systems, as you might want to trigger changes for C when anything it includes changes. This is pretty straightforward right now, but would be a lot more complex in a world with chained imports.

In addition, it's also easy to reason about how precedence is determined. You can read the file top to bottom, and see where configurations will get overwritten (unless you decide to put includes after inputs for some reason). In a world with chained imports, you have two dimensions to track: both the depth of the import, and the position of the import configuration block in HCL in a given file.

Also, I definitely don't think these should be called imports, as that conflicts with OpenTofu import blocks, and that will likely confuse people.

Personally, I'm for closing out the RFC as will not do, and achieving DRY-er configurations via Stacks.

I'll share my thoughts on the linked issue as well, and see if the community agrees.