internal-json logger improvements: "action":"stop" `id` handling

[qknight]

Is your feature request related to a problem?

Using nix build to build from cargo makes logging a challenge, as nix does:

• mixes log outputs of different builds
• when having one error, prints errors twice
• can't attribute error messages to the respective 'id'
• there is no id: 0 for the main nix build call

Using nix (Nix) 2.28.3 at time of writing.

{
  pkgs ? import <nixpkgs> { },
}:
{

  b = pkgs.stdenv.mkDerivation {
    name = "asdf b";
    src = ./in;
    phases = [ "installPhase" ];
    installPhase = ''
          mkdir -p $out
          echo "asdf1" > $out/asdf
      exit 1
    '';
  };
  a = pkgs.stdenv.mkDerivation {
    name = "asdf a";
    src = ./in;
    phases = [ "installPhase" ];
    installPhase = ''
          mkdir -p $out
          echo "asdf1" > $out/asdf
      exit 1
    '';
  };
}

nix build --file default.nix --keep-going --log-format internal-json

causes

@nix {"action":"stop","id":126284923404294}
@nix {"action":"stop","id":126284923404293}
@nix {"action":"stop","id":126284923404291}
@nix {"action":"stop","id":126284923404290}
@nix {"action":"stop","id":126284923404289}
@nix {"action":"msg","column":null,"file":null,"level":0,"line":null,"msg":"\u001b[31;1merror:\u001b[0m \u001b[0mbuilder for '\u001b[35;1m/nix/store/0y0jz1i6sia87lh1z70g0b8w8737imb9-asdf-b.drv\u001b[0m' failed with exit code 1;\n       last 1 log lines:\n       > Running phase: installPhase\n       For full logs, run:\n         \u001b[1mnix log /nix/store/0y0jz1i6sia87lh1z70g0b8w8737imb9-asdf-b.drv\u001b[0m","raw_msg":"\u001b[0mbuilder for '\u001b[35;1m/nix/store/0y0jz1i6sia87lh1z70g0b8w8737imb9-asdf-b.drv\u001b[0m' failed with exit code 1;\nlast 1 log lines:\n> Running phase: installPhase\nFor full logs, run:\n  \u001b[1mnix log /nix/store/0y0jz1i6sia87lh1z70g0b8w8737imb9-asdf-b.drv\u001b[0m"}
@nix {"action":"msg","column":null,"file":null,"level":0,"line":null,"msg":"\u001b[31;1merror:\u001b[0m \u001b[0mbuilder for '\u001b[35;1m/nix/store/da806ys08lnfspf1czkgspi71awxri60-asdf-a.drv\u001b[0m' failed with exit code 1;\n       last 1 log lines:\n       > Running phase: installPhase\n       For full logs, run:\n         \u001b[1mnix log /nix/store/da806ys08lnfspf1czkgspi71awxri60-asdf-a.drv\u001b[0m","raw_msg":"\u001b[0mbuilder for '\u001b[35;1m/nix/store/da806ys08lnfspf1czkgspi71awxri60-asdf-a.drv\u001b[0m' failed with exit code 1;\nlast 1 log lines:\n> Running phase: installPhase\nFor full logs, run:\n  \u001b[1mnix log /nix/store/da806ys08lnfspf1czkgspi71awxri60-asdf-a.drv\u001b[0m"}
@nix {"action":"msg","column":null,"file":null,"level":0,"line":null,"msg":"\u001b[31;1merror:\u001b[0m build of \u001b[35;1m'/nix/store/0y0jz1i6sia87lh1z70g0b8w8737imb9-asdf-b.drv^out', '/nix/store/da806ys08lnfspf1czkgspi71awxri60-asdf-a.drv^out'\u001b[0m failed","raw_msg":"build of \u001b[35;1m'/nix/store/0y0jz1i6sia87lh1z70g0b8w8737imb9-asdf-b.drv^out', '/nix/store/da806ys08lnfspf1czkgspi71awxri60-asdf-a.drv^out'\u001b[0m failed"}

Proposed solution

Assuming these two lines were form the same drv build:

@nix {"action":"stop","id":126284923404291}
@nix {"action":"msg","column":null,"file":null,"level":0,"line":null,"msg":"\u001b[31;1merror:\u001b[0m \u001b[0mbuilder for '\u001b[35;1m/nix/store/0y0jz1i6sia87lh1z70g0b8w8737imb9-asdf-b.drv\u001b[0m' failed with exit code 1;\n       last 1 log lines:\n       > Running phase: installPhase\n       For full logs, run:\n         \u001b[1mnix log /nix/store/0y0jz1i6sia87lh1z70g0b8w8737imb9-asdf-b.drv\u001b[0m","raw_msg":"\u001b[0mbuilder for '\u001b[35;1m/nix/store/0y0jz1i6sia87lh1z70g0b8w8737imb9-asdf-b.drv\u001b[0m' failed with exit code 1;\nlast 1 log lines:\n> Running phase: installPhase\nFor full logs, run:\n  \u001b[1mnix log /nix/store/0y0jz1i6sia87lh1z70g0b8w8737imb9-asdf-b.drv\u001b[0m"}

• both lines should be merged into one
• a "code": 0 should be added if no error, some other code for errors: maybe a derivation can delegate an error code used in the build and return that?

Similar to individual drvs, the nix build call itself should have id: 0 and handle messages and exists similar.

On id:0 success:

@nix {"action":"stop","id":0, "code":0}

On id:0 errors:

@nix {"action":"stop","id":0, "code":1, "failed":["/nix/store/0y0jz1i6sia87lh1z70g0b8w8737imb9-asdf-b.drv","/nix/store/da806ys08lnfspf1czkgspi71awxri60-asdf-a.drv"], "msg":"... some error message for the shell to print"}

Additional context

cargo build only shows warnings and errors on builds. With this extension I can easily filter successful targets and not display them at all. Users are only interested in builds which failed in order to fix them ;-)

Checklist

• checked latest Nix manual (source)
• checked open feature issues and pull requests for possible duplicates

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