Node package-lock v2

[wmertens]

Putting this in a separate PR from #195 to split up discussions.

[wmertens]

I think the test error may be because I'm adding source info for the main package? The reason for that is to be able to pass metadata like hasInstallScripts, and I can only do that via source, right?

My next optimization will be to split the build into

• a pure module unpack with bin symlinks which doesn't call any scripts (thoughts on getting around #214 ?)
• then a built module if hasInstallScripts is true, temporarily adding pure-source cycle members to the build
• then cyclic packages that combine the previous by copying

This way, if the node version changes, it only rebuilds packages with install scripts.

[DavHau]

I noticed that a failed jsonschema validation did not lead to an error in the example tests. This is fixed in 9331fb1376068e24f0ab5080aec85f43a369ebdb.

You can see the schema that the dream-lock is validated against in src/specifications/dream-lock-schema.json.

Instead of adding information to the sources, you can use the subsystmAttrs field to add extra data. This will end up in _subsystem in the final dream-lock and is passed as subsystemAttrs to the builders.

This way, if the node version changes, it only rebuilds packages with install scripts.

Sounds like a nice optimization. But I'd suggest that we first integrate the simplest possible version of the new build logic. Probably as a separate builder. Then test this against many packages. Once we have confidence in it, we can make it the default. That might be valuable even without further optimizations.

[nixos-discourse]

This pull request has been mentioned on NixOS Discourse. There might be relevant details there:

https://discourse.nixos.org/t/yarn-plugnplay-and-direnv-packaging/19759/26

[xanderio]

Support for package-lock v2 and v3 in dream2nix would remove a major hurdle for me in adopting dream2nix. Is there anything that I can help with to get this merged?

[teto]

I was wondering why dream2nix wouldnt work with my project (lockfile version 3) until I stumbled on this. I am trying this out but nix can't find the git revision. I've been trying to run nix flake update (2.16) but it couldn't find mach-nix, the following fixed this:

-      url = "mach-nix";                                                                       
+      url = "github:DavHau/mach-nix"; 

then I tried to use my fork https://github.com/teto/dream2nix/tree/node-pkg-v2 on my project, which failed with

         at /nix/store/mc6avkywi5473yylvyh64fcl62kdhlgx-source/e2e-candidate/flake.nix:49:6:

           48|   in
           49|     (dream2nix.lib.makeFlakeOutputs {
             |      ^
           50|       pname = "toto";

       error: function 'makeFlakeOutputs' called with unexpected argument 'projects'

@wmertens would you mind rebasing this please ?

[wmertens]

@teto I'm kinda burnt out on this, maybe I'll revisit this but right now I have too many other projects. I did notice that nixpkgs now has buildNpmPackage, not sure if that's helpful?