node-gyp-build: /usr/bin/env: bad interpreter: No such file or directory

[nixinator]

something has either changed in nixpkgs or npm , and things that built are no longer building (such is life).

you can recreate it with the hypercore package here

NixOS/nixpkgs#142196

I'm working on another repo which reports when building with node2nix. :-( . https://discourse.nixos.org/t/nodejs-application-in-nix/16196

> node-gyp-build

sh: /nix/store/pf5dl9n7hsrfzamm16wpzjbf65ic471i-application-0.1.0/lib/node_modules/application/node_modules/.bin/node-gyp-build: /usr/bin/env: bad interpreter: No such file or directory
npm ERR! code ELIFECYCLE
npm ERR! errno 126
npm ERR! [email protected] install: `node-gyp-build`
npm ERR! Exit status 126
npm ERR! 
npm ERR! Failed at the [email protected] install script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

I think the interesting thing here, they are both failing with the same 'bad interpreter' , may be a clue, or may be a red herring.

'in npm space, no one can hear you scream'

[svanderburg]

This was a really tricky package! As the discourse item describes, you should create an override so that node-gyp-build can be found.

However, what I noticed is that as soon as this dependency is provided, it still attempts to invoke node-gyp-build from the project's node_modules/ folder, and it turns out that the shebang of that executable isn't patched, causing that particular shebang error.

I ended up implementing an override.nix expression that looks as follows:

{pkgs ? import <nixpkgs> {
    inherit system;
}, system ? builtins.currentSystem}:

let
  nodePackages = import ./default.nix {
    inherit pkgs system;
  };
in
nodePackages // {
  hypercore = nodePackages.hypercore.override {
    buildInputs = [ pkgs.nodePackages.node-gyp-build ];
    preRebuild = ''
      sed -i -e "s|#!/usr/bin/env node|#! ${pkgs.nodejs}/bin/node|" node_modules/node-gyp-build/bin.js
    '';
  };
}

with the following command I was able to build it:

$ nix-build -A hypercore

I think the most annoying part is the patchShebangs command in stdenv generic builder in Nixpkgs for some strange reason is unable to detect the shebang line. Even if I directly provide the path to the bin.js file to the patchShebangs command, it still gets ignored.

Fortunately, I manual sed instruction seems to do the trick.

[Artturin]

I think the most annoying part is the patchShebangs command in stdenv generic builder in Nixpkgs for some strange reason is unable to detect the shebang line. Even if I directly provide the path to the bin.js file to the patchShebangs command, it still gets ignored.

https://github.com/NixOS/nixpkgs/blob/master/pkgs/build-support/setup-hooks/patch-shebangs.sh

This setup hook causes the fixup phase to rewrite all script
interpreter file names (`#! /path') to paths found in $PATH. E.g.,
/bin/sh will be rewritten to /nix/store/-some-bash/bin/sh.
/usr/bin/env gets special treatment so that ".../bin/env python" is
rewritten to /nix/store//bin/python. Interpreters that are
already in the store are left untouched.
A script file must be marked as executable, otherwise it will not be
considered.

https://github.com/NixOS/nixpkgs/blob/e95ee1fb3697b67268b0076abc6d74b2d8de6f2a/pkgs/build-support/setup-hooks/patch-shebangs.sh#L51
https://github.com/NixOS/nixpkgs/blob/e95ee1fb3697b67268b0076abc6d74b2d8de6f2a/pkgs/stdenv/generic/setup.sh#L231

[nixinator]

Great Find! Explains why it's not patching those files, can this behaviour be changed, especially in nodejs is being naughty and not marking scripts with an executable bit. I wonder what other horrible behaviour it has.

[Artturin]

couple ideas i have:
add a command flag that makes patchShebangs ignore the executable bit and patch regardless
or add a env var that can be set to always patch shebangs

[svanderburg]

It would be nice if Nixpkgs' patchShebangs can be fixed or changed with an optional flag to make this possible. In theory, it's also possible to fix it in node-env.nix, but this sort means that we provide a solution to this problem on the wrong level.

I can also image that other packages in Nixpkgs, i.e. non-NPM packages, could run into the similar problems.

[runeksvendsen]

@svanderburg for some reason your suggested fix doesn't work for me (nor do these instructions). Specifically, the nodePackages expression created by importing ./default.nix does not have any top-level package name attributes (e.g. hypercore). It has only the attributes: args, sources, nodeDependencies, tarball, package, shell. I have tried with both v1.10.0 and v1.9.0 and I get the same results.

The following repo contains the source files (package.json and package-lock.json) from which the rest is generated (default.nix, node-env.nix, node-packages.nix), as well as the override.nix file whose newNodePackages attribute (created by following the guide) doesn't work: https://github.com/runeksvendsen/node2nix-patch-docs