dont create dangling symlink build/Release/libzim.so

[milahu]

this line

node-libzim/bundle-libzim.js

Line 31 in 264affa

exec("ln -sf build/Release/libzim.so.9 build/Release/libzim.so"); // convenience only, not required

creates a dangling symlink build/Release/libzim.so
if the file build/Release/libzim.so.9 does not exist

this happens when building with system libzim

node-libzim/binding.gyp

Line 5 in 264affa

"libzim_local": "false", # change this to use system-installed libzim

[kelson42]

Considering the line just before is

exec(`cp download/lib/${libDir}/libzim.so.9 build/Release/libzim.so.9`);`

I hardly see how this could be a dangling link!?

I'm more disturbed by the comment "// convenience only, not required". Either this is useful and kept, or it is not and removed.

[milahu]

exec(`cp download/lib/${libDir}/libzim.so.9 build/Release/libzim.so.9`);`

apparently, the copy silently fails
because the source file does not exist
because the build is using the system libzim.so

[milahu]

kelson42 closed this as not planned

still an issue

trivially fixed by adding this to bundle-libzim.js

const bindingGypText = fs.readFileSync("binding.gyp", { encoding: "utf8" });
if (bindingGypText.match(/"libzim_local":\s*"true"/)) {
  console.log("the build is using system libzim -> not bundling libzim");
  process.exit();
}

[milahu]

this happens when building with system libzim

i should have shared my use case
project-nomad.nix

  # fix: @openzim/libzim tries to download libzim
  # npm error path /build/source/admin/node_modules/@openzim/libzim
  # npm error command failed
  # npm error command sh -c npm run download && node-gyp rebuild -v && npm run bundle
  #
  # dont run the "install" script of @openzim/libzim
  # https://github.com/openzim/node-libzim/blob/main/package.json
  # "install": "npm run download && node-gyp rebuild -v && npm run bundle",
  # npm-config-hook.sh runs: npm rebuild $npmRebuildFlags
  npmRebuildFlags = [ "--ignore-scripts" ];

  # fix: Error: Could not locate the bindings file zim_binding.node
  # https://github.com/openzim/node-libzim
  postConfigure = ''
    pushd node_modules/@openzim/libzim

    # use libzim via pkg-config
    substituteInPlace binding.gyp \
      --replace-fail \
        '"libzim_local": "false"' \
        '"libzim_local": "true"'

    npm run build

    # fix: dont create dangling symlink
    # https://github.com/openzim/node-libzim/issues/186
    rm -v build/Release/libzim.so || true

    popd
  '';

git clone --depth=1 https://github.com/milahu/nur-packages
cd nur-packages
nix-build . -A project-nomad

$ ldd result/lib/node_modules/project-nomad-admin/node_modules/@openzim/libzim/build/Release/zim_binding.node|grep libzim
        libzim.so.9 => /nix/store/snbf955zln63ply1g3ca2cahw9nw72lp-libzim-9.5.0/lib/libzim.so.9 (0x0000773e8880c000)

test: write.js

// fix:
// Error [ERR_MODULE_NOT_FOUND]: Cannot find package '@openzim/libzim' imported from /home/user/src/milahu/nur-packages/write.js
// import { Creator, StringItem } from "@openzim/libzim";
const { Creator, StringItem } = require("@openzim/libzim");

$ NODE_PATH=$(readlink result)/lib/node_modules/project-nomad-admin/node_modules node write.js
Starting
Resolve redirect
set index
Done Writing

so... this just works for me