bant: init at 0.1.5

[hzeller]

Description of changes

From the README : Utility to support projects using the bazel build system, in particular C++ projects.

• Cleaning up BUILD files by adding missing, and removing superflous, dependencies.
• Extract interesting project information such as the dependency graph, headers provided by which libraries ....

Upstream v0.1.5 Release Notes

Things done

• Built on platform(s)
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• For non-Linux: Is sandboxing enabled in nix.conf? (See Nix manual)
  • sandbox = relaxed
  • sandbox = true
• Tested, as applicable:
  • NixOS test(s) (look inside nixos/tests)
  • and/or package tests
  • or, for functions and "core" functionality, tests in lib/tests or pkgs/test
  • made sure NixOS tests are linked to the relevant packages
• Tested compilation of all packages that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review rev HEAD". Note: all changes have to be committed, also see nixpkgs-review usage
• Tested basic functionality of all binary files (usually in ./result/bin/)
• 24.11 Release Notes (or backporting 23.11 and 24.05 Release notes)
  • (Package updates) Added a release notes entry if the change is major or breaking
  • (Module updates) Added a release notes entry if the change is significant
  • (Module addition) Added a release notes entry if adding a new NixOS module
• Fits CONTRIBUTING.md.

---

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[hzeller]

This is a little tool I wrote that helps exploring bazel projects and also provides some dependency cleaning features.

However it seems to not work well to build as package on nix. I suspect this is because I am using bzlmod ?

Observed

• Even after the fixed derivation of all dependencies has been determined, bazel still seems to want to talk to the bazel repository and errors such as Error accessing registry https://bcr.bazel.build/: Unknown host: bcr.bazel.build show up after switching to sandboxing.
• In general, the fixed derivation hash seems to be different on different platforms. Not only between platforms (CI shows difference between aarch64 and x86_64 Linux), but as well on the same platform: the CI has a different hash for x86_64 than even my own x86_64 machine at home.
• I even removed one of the not really needed dependencies in a patch, as you see in the commit, but also no difference (edit: now removed that again as it was not influencing the issue)

Are bzlmod projects not well-supported currently ?
Sending to @aherrmann for review as you have a good knowledge of both Nix and Bazel.

[hzeller]

Maybe folks from @NixOS/bazel know some way to get this unstuck ?

[hzeller]

New bant release came out in the meantime, changed to version 0.1.5

This can be made work with something @lromor has been working on: if the external bzlmod repository is bulit as fixed derivation, it can be passed to bazel with it not attempting to download the registry again after the build-phase:

lromor@ea780ca

Something like that would probably need to go into build-bazel-package, maybe with an override for the user to change the desired revision of the bazel-central-registry ? Leonardo, I think it would be good to create a pull request for nixpkgs changing the build-bazel-package and have the @NixOS/bazel maintainers review and help refine it.

(I could compile this PR when I patched in @lromor 's change to build-bazel-package)

[lromor]

For now I'll prepare a PR that uses overrideAttrs to add these changes as least invasive solution.

[lromor]

@hzeller , I found a simpler way:

{
  lib,
  stdenv,
  buildBazelPackage,
  fetchFromGitHub,
  bazel_6,
  jdk,
  git,
}:

let
  registry = stdenv.mkDerivation {
    name = "bazel-central-registry";
    dontBuild = true;
    src = fetchFromGitHub {
      owner = "bazelbuild";
      repo = "bazel-central-registry";
      rev = "1c729c2775715fd98f0f948a512eb173213250da";
      hash = "sha256-1iaDDM8/v8KCOUjPgLUtZVta7rMzwlIK//cCoLUrb/s=";
    };
    installPhase = ''
       cp -r $src $out
    '';
  };
in buildBazelPackage rec {
  pname = "bant";
  version = "0.1.5";

  src = fetchFromGitHub {
    owner = "hzeller";
    repo = "bant";
    rev = "v${version}";
    hash = "sha256-3xGAznR/IHQHY1ISqmU8NxI90Pl57cdYeRDeLVh9L08=";
  };

  bazelFlags = ["--registry" "file://${registry}"];

  postPatch = ''
    patchShebangs scripts/create-workspace-status.sh
  '';

  fetchAttrs = {
    sha256 = "sha256-ACJqybpHoMSg2ApGWkIyhdAQjIhb8gxUdo8SuWJvTNE=";
  };

  nativeBuildInputs = [
    jdk
    git
  ];
  bazel = bazel_6;

  bazelBuildFlags = [ "-c opt" ];
  bazelTestTargets = [ "//..." ];
  bazelTargets = [ "//bant:bant" ];

  buildAttrs = {
    installPhase = ''
      install -D --strip bazel-bin/bant/bant "$out/bin/bant"
    '';
  };

  meta = with lib; {
    description = "Bazel/Build Analysis and Navigation Tool";
    homepage = "http://bant.build/";
    license = licenses.asl20;
    maintainers = with maintainers; [ hzeller ];
    platforms = platforms.all;
  };
}

Note that I need a different hash, not sure why.

[hzeller]

Perfect, thanks @lromor ! I think you should create a fresh bant pull request with your bazel compile improvements, then I retract this PR.

[hzeller]

Chatted offline with @lromor : he'll prepare a nixpkgs pull request that includes the bazel registry as part of the derivation.
Closing this one.