Support tfmigrate plan / apply automatically (without PR label)

[ponkio-o]

Feature Overview

I would like to execute tfmigrate plan and tfmigrate apply automatically. In other words, I would like to execute these commands without PR label.

My understanding is that need to add the label (e.g. tfmigrate:aws/env/prd) to PR when if execute tfmigrate plan and apply.
https://suzuki-shunsuke.github.io/tfaction/docs/feature/tfmigrate/

Why is the feature needed?

Some reasons:

• Difficult to understand because terraform plan is automatically executed, whereas tfmigrate plan isn't automatically executed.
• Even if use a prefix such as tfmigrate:, it is difficult to find a label among the many available in PR.

Example Code

To achieve this, it is necessary to detect changes in the tfmigrate migration file that is committed each working directory.
https://github.com/minamijoyo/tfmigrate#migration-file

Note

No response

[suzuki-shunsuke]

Thank you for your feedback!
That makes sense.

IIRC, I decided to use labels to prevent tfmigrate from being run unexpectedly when moving working directories or moving migration files.
But now I don't think this is valid.
tfmigrate is idempotent unless you don't change the migration file paths.
You can also remove old migration files if necessary.

To implement the feature, tfaction needs to do following things:

1. Detect .tfmigrate.hcl
2. Read dir from .tfmigrate.hcl
3. Check if any migration files are changed
4. If .tfmigrate.hcl or migration files are changed, run tfmigrate

https://github.com/suzuki-shunsuke/tfaction/tree/main/js/src/list-targets-with-changed-files

To parse .tfmigrate.hcl properly, we need to parse HCL.
I can't find active HCL parser written in JavaScript.
Perhaps we need to execute hcledit or something in JavaScript.
Or regular expression may be enough.

[ponkio-o]

Thank you for your reply!
In addition, tfmigrate supports JSON files, so these must also be considered.

The extension of file must be .hcl(for HCL native syntax) or .json(for HCL JSON syntax).

https://github.com/minamijoyo/tfmigrate#configuration-file

It may be easier to read from TypeScript if it is converted to a JSON file with a CLI such as hcl2json.
https://github.com/tmccombs/hcl2json

[suzuki-shunsuke]

https://github.com/minamijoyo/tfmigrate?tab=readme-ov-file#migration-file

The extension of file must be .hcl(for HCL native syntax) or .json(for HCL JSON syntax).

I see.