greater granularity on migrate-state approvals for CI / headless runs

[novas0x2a]

Terraform Version

Terraform v1.1.9
on linux_amd64

but I've diff'd internal/command/meta_backend_migrate.go between 1.1.9 and main and there haven't been any relevant changes to the flow since then.

Use Cases

I'm trying to orchestrate a state migration via CI using init -migrate-state. The issue is:

• In the simple case (empty destination state) I want to permit the migration in a headless fashion (like -force was passed, no input required)
• In the complex case (non-empty destination state) I want the migration to fail; humans will need to resolve this before trying again.

Attempted Solutions

As far as I know there's no solution entirely within terraform. My current plan is to manually copy the state from the source to the destination, checking for and forbidding an overwrite, before calling terraform (in a normal fashion; TF won't know in this scenario that a migration happened).

Proposal

The most complex version of this might be to have some sort of generic functionality to agree to specific input prompts without agreeing to others; for example, if the prompt ID was split into backend-migrate-to-backend-empty and backend-migrate-to-backend-nonempty, and also if I could agree to specific prompts like -input=backend-migrate-to-backend-empty=true -input=false that would solve the problem in a really complete fashion.

The simplest version of this might be something like -migrate-state=if-empty or something like that.

References

I didn't find anything addressing this case.

[crw]

Thanks for this request!