Hi @wata727 ,
Thanks for your thoughtfully posed questions, I’ll do my best to answer here!
Should OSS with partial copy of source code change license to BSL?
HashiCorp BSL does not impose copyleft requirements for your OSS project, so you do not need to change your project’s overall license to BSL. However, the clarifications in FAQ 14 do still apply. In particular, if your copy/fork of Terraform internal packages are based on HashiCorp BSL licensed source code, then these derivative copies will need to also be BSL licensed with the same terms.
Should OSS that uses BSL-licensed source code as a library change license to BSL?
No. It will be bound by both licenses as it is mixed with BSL source code and the existing license of your project.
Does the TFLint Ruleset powered by OPA violate BSL?
After an initial review of the plugin on GitHub, it is not in violation of BSL as it does not appear to host or embed. If the scope of the plugin changes and you have additional questions, please reach out to us.
If you would like help with your use case more directly, please email licensing@hashicorp.com!