convert node modules to tgz

script.js

const { existSync, writeFileSync, mkdirSync } = require('fs');
const { execSync } = require('child_process');

if (!existsSync('package.json')) {
    writeFileSync('package.json', JSON.stringify({ dependencies: {} }, null, 2));
}

function saferequire(name) {
    try {
        return require(name);
    } catch (error) {
        console.log(`installing package ${name}`);
        console.log(execSync(`npm install ${name} --save-dev`).toString());
        return require(name);
    }
}


const download = require('download-file');
const packageLockJson = require('./package-lock.json');

const tarballsDirectory = './tarballs';
const tarballs = [];

enumerateDependencies(packageLockJson.dependencies);

function enumerateDependencies(dependencies) {
    for (const dependencyName in dependencies) {
        const dependency = dependencies[dependencyName];
        if (dependency.resolved) {
            tarballs.push({
                filename: `${dependencyName}-${dependency.version}.tgz`,
                url: dependency.resolved
            });
        }
        if (dependency.dependencies) {
            enumerateDependencies(dependency.dependencies);
        }
    }
}

if (!existSync(tarballsDirectory)) {
    mkdirSync(tarballsDirectory);
}
tarballs.forEach(tarball => {
    download(tarball.url, {
        directory: tarballsDirectory,
        filename: tarball.filename
    });
});

function download(url, dest, cb) {
    const file = fs.createWriteStream(dest);
    const request = https.get(url, response => {
        response.pipe(file);
        file.on('finish', () => {
            file.close(cb);
        });
    });
}

run with node inside a directory that has a package-lock.json file