binary.js

var fs = require("fs");
var path = require("path");
var package = require("./package.json");

module.exports = function () {
    var os = process.env.BINWRAP_PLATFORM || process.platform;
    var arch = process.env.BINWRAP_ARCH || process.arch;

    var requested = `${os}-${arch}`;
    var current = `${process.platform}-${process.arch}`;
    var subPackageName = `@lydell/elm-json-${requested}`;

    if (requested !== current) {
        console.error(
            `WARNING: Using binaries for the requested platform (${requested}) instead of for the actual platform (${current}).`
        );
    } else if (requested === "linux-arm64") {
        // This binary is 32-bit but also works on 64-bit ARM.
        subPackageName = "@lydell/elm-json-linux-arm";
    }

    if (!(subPackageName in package.optionalDependencies)) {
        exitFailure(
            `The elm-json npm package does not support your platform (${requested}).`
        );
    }

    var fileName = os === "win32" ? "elm-json.exe" : "elm-json";

    try {
        var subBinaryPath = require.resolve(`${subPackageName}/${fileName}`);
    } catch (error) {
        if (error && error.code === "MODULE_NOT_FOUND") {
            exitFailure(missingSubPackageHelp(subPackageName));
        } else {
            exitFailure(
                `I had trouble requiring the binary package for your platform (${subPackageName}):\n\n${error}`
            );
        }
    }

    // Yarn 2 and later ("Berry") always invokes `node` (regardless of configuration)
    // so we cannot do any optimizations there.
    var isYarnBerry = /\byarn\/(?!1\.)/.test(
        process.env.npm_config_user_agent || ""
    );

    // On Windows, npm always invokes `node` so we cannot do any optimizations there either.
    if (os === "win32" || isYarnBerry) {
        return subBinaryPath;
    }

    var binaryPath = path.resolve(__dirname, package.bin["elm-json"]);
    var tmpPath = binaryPath + ".tmp";

    try {
        // Atomically replace the file with a hard link to the binary as an optimization.
        fs.linkSync(subBinaryPath, tmpPath);
        fs.renameSync(tmpPath, binaryPath);
    } catch (error) {
        exitFailure(
            `I had some trouble writing file to disk. It is saying:\n\n${error}`
        );
    }

    return binaryPath;
};

function exitFailure(message) {
    console.error(
        `
-- ERROR -----------------------------------------------------------------------

${message}

NOTE: You can avoid npm entirely by downloading directly from:
https://github.com/zwilias/elm-json/releases/tag/v${package.version}
All this package does is distribute a file from there.

--------------------------------------------------------------------------------
    `.trim()
    );
    process.exit(1);
}

function missingSubPackageHelp(subPackageName) {
    return `
I support your platform, but I could not find the binary package (${subPackageName}) for it!

This can happen if you use the "--omit=optional" (or "--no-optional") npm flag.
The "optionalDependencies" package.json feature is used by elm-json to install the correct
binary executable for your current platform. Remove that flag to use elm-json.

This can also happen if the "node_modules" folder was copied between two operating systems
that need different binaries - including "virtual" operating systems like Docker and WSL.
If so, try installing with npm rather than copying "node_modules".
    `.trim();
}