configure_me cooperation

[Kixunil]

Your crate looks great, I look forward into trying it out! I'm going to package some services and I was thinking about integrating my crate configure_me with your crate.

First, I'd like to integrate man pages - they are already automatically generated from the configuration specification file.

Second, I was thinking about adding debconf support to configure_me, so it can automatically generate templates and postinst script (possibly another binary, though)

Thirdly I'd love to support bash completions at some point - another thing worth integrating.

I'm not sure how to do all this, but I was thinking that cargo-deb could set some environment variables e.g. MAN_OUTDIR, DEBCONF_TEMPLATE_OUT (needs append I think), and BASH_COMPLETION_OUTDIR for bash completions.

What do you think?

[kornelski]

Placement of generated files is an unsolved problem for Cargo: rust-lang/cargo#5457

I don't want to invent a method for finding these files without coordination with the rest of the ecosystem, so I've made a post seeking feedback about this:

https://users.rust-lang.org/t/pre-rfc-generating-assets-products-during-cargo-build/32824

[Kixunil]

That's very reasonable, thanks for writing that post! I replied there about more general stuff. I have an idea that we could already play with some solution for now and clearly document it as an unstable experiment. (Putting it behind a feature flag sounds like a good idea.) That way it'd be easier to figure out what works. Similarly to how famous try!() macro got converted to ? operator.

I'm willing to make a PR, but I'd like to know which approach seems like the best for now, so that I start straight away with that. I'm leaning to env var approach, but you seem to prefer cargo directive. If you can point me at a good documentation on reading cargo directives from cargo tools and a reason for chosing that approach, I can do it.

I know about at least two projects that might want to use this, so we already have some real-life code to test it on.

[kornelski]

From the user forum discussion this approach seems most promising:

https://matklad.github.io/2018/01/03/make-your-own-make.html

given that it can be made to work with plain Cargo without 3rd party tools.

So I think we could establish some convention:

1. If there's tools/Cargo.toml try running cargo run -p tools --bin postbuild

2. Expect output in target/assets/<crate-name>/ (workspaces share target dir between crates)

I could put that in a lightweight crate to ensure handling is consistent between tools.