How to improve doclicense? Integrate with https://reuse.software/?

[ypid]

First of all: I am not a lawyer

The Problem

Currently, doclicense is designed to put a footer into the document like this:

(Specifying one license only).

But are you sure that?

1. All included text or artifact (image/figure/table/source code listing) are under this license? Or can they be released under this license?
2. What the original licensing and copyright situation of all the source files that end up or influence the final document is?

Proposal

https://reuse.software/ was created to address this but with focus on software projects. I made the source code of doclicense itself compliant with this spec in #71. This got me thinking and I propose the following:

• Include a hint in the docs that document source files should be compliant with the REUSE Specification. Add section to doclicense what license to use and REUSE spec #73
• Check the license of all files included in LaTeX compilation that are covered by the REUSE Specification and if they are different to the "main license of the document" (as set with the package options), emit warnings during compilation.
• Provide a macro to attribute artifacts differently, based on REUSE Specification.

The question is if we could go further than that. Would it be useful for the package to check all included files for their license, if it is the same license, pick that (making the package options optional). I am not sure about that.

Further discussion is welcome. I have no timeline if or when I implement this.