Support relative paths in `:local/root`

[volisoft]

Seems like relative paths in :local/root are not supported. Here's an example project. Here's the error indicating that local library at ../../components/liba cannot be found:

       last 10 log lines:
       > no configure script, doing nothing
       > Running phase: preBuildPhase
       > Running phase: buildPhase
       > Picked up JAVA_TOOL_OPTIONS: -Duser.home=/nix/store/33qbkrdp0hij5x5iq0xljqw6i36zgld4-clj-cache
       > check com.demo.liba.interface for :gen-class
       > Execution error (ExceptionInfo) at clojure.tools.deps.extensions.local/ensure-file (local.clj:41).
       > Local lib com.demo/liba not found: /components/liba

Such relative paths are supported by Clojure deps and are common in polylith projects.

Originally posted by @volisoft in https://github.com/jlesquembre/clj-nix/issues/7#issuecomment-2282244478

[jlesquembre]

thanks for the example project, looks like a bug, I'll take a look

[jlesquembre]

I was playing with polylith, and the way to build an uberjar is a bit different, it doesn't work with the default clj-nix builder, but that has nothing to do with :local/root (which are supported by clj-nix) As an example, you can see how to build a polylith project with clj-nix here:

https://github.com/jlesquembre/usermanager-example

Run:

nix build .
result/bin/main

Take a look at the flake.nix file: https://github.com/jlesquembre/usermanager-example/commit/e4a71afbd3a86092d9b9ee8500d61fc20b9b4715

Notice that flake.nix needs to be at the root of the project, and that we need a custom build.clj file.

Maybe we could try to add support for polylith, to avoid the need for a custom build.clj file.

[volisoft]

Thank you for taking a look. Is it possible to keep flake.nix in the projects directory?

In my actual repository there's already a flake.nix in the project's root, which sets up development tools. Also, potentially, there can be multiple separate projects under projects directory, each with it's own assets and build process.

[jlesquembre]

Is it possible to keep flake.nix in the projects directory?

It is, but instead of doing that, I'd create multiple packages within the flake, something like this:

packages = {
        webapp = clj-nix.lib.mkCljApp ...;
        cliapp = clj-nix.lib.mkCljApp ...;
};

if your repository is open source, could you share a link to it?

[volisoft]

That looks interesting. Will each project require a separate deps.lock file? If so, should the lock files be placed in the appropriate project's directory?

I'm afraid the repository I'm working with is private, so I cannot share it. However, it's a typical Polylith mono-repository. I can add another sub-project to the demo project if you need something for testing.

[jlesquembre]

You only need one deps.lock file. clj-nix looks for all deps.edn files in the repository. You can include/exclude certain files and aliases. For details, see: https://jlesquembre.github.io/clj-nix/lock-file/

[volisoft]

That works. Thank you for your help!

[jlesquembre]

@volisoft I'd like to play around with Polylith, and maybe add support for it in clj-nix. However, given the flexibility of Polylith, it might be more practical to provide a custom build.clj.

[volisoft]

I believe build.clj is a suitable solution. Since others may encounter this situation as well, adding a hint in the documentation pointing to this solution could be very helpful.