[node.js] NPM clean modules

You can take advantage of the 'npm cache' command which downloads the package tarball and unpacks it into the npm cache directory.

The source can then be copied in.

Using ideas gleaned from https://groups.google.com/forum/?fromgroups=#!topic/npm-/mwLuZZkHkfU I came up with the following node script. No warranties, YMMV, etcetera.

var fs = require('fs'),
path = require('path'),
exec = require('child_process').exec,
util = require('util');

var packageFileName = 'package.json';
var modulesDirName = 'node_modules';
var cacheDirectory = process.cwd();
var npmCacheAddMask = 'npm cache add %s@%s; echo %s';
var sourceDirMask = '%s/%s/%s/package';
var targetDirMask = '%s/node_modules/%s';

function deleteFolder(folder) {
    if (fs.existsSync(folder)) {
        var files = fs.readdirSync(folder);
        files.forEach(function(file) {
            file = folder + "/" + file;
            if (fs.lstatSync(file).isDirectory()) {
                deleteFolder(file);
            } else {
                fs.unlinkSync(file);
            }
        });
        fs.rmdirSync(folder);
    }
}

function downloadSource(folder) {
    var packageFile = path.join(folder, packageFileName);
    if (fs.existsSync(packageFile)) {
        var data = fs.readFileSync(packageFile);
        var package = JSON.parse(data);

        function getVersion(data) {
            var version = data.match(/-([^-]+)\.tgz/);
            return version[1];
        }

        var callback = function(error, stdout, stderr) {
            var dependency = stdout.trim();
            var version = getVersion(stderr);
            var sourceDir = util.format(sourceDirMask, cacheDirectory, dependency, version);
            var targetDir = util.format(targetDirMask, folder, dependency);
            var modulesDir = folder + '/' + modulesDirName;

            if (!fs.existsSync(modulesDir)) {
                fs.mkdirSync(modulesDir);
            }

            fs.renameSync(sourceDir, targetDir);
            deleteFolder(cacheDirectory + '/' + dependency);
            downloadSource(targetDir);
        };

        for (dependency in package.dependencies) {
            var version = package.dependencies[dependency];
            exec(util.format(npmCacheAddMask, dependency, version, dependency), callback);
        }
    }
}

if (!fs.existsSync(path.join(process.cwd(), packageFileName))) {
    console.log(util.format("Unable to find file '%s'.", packageFileName));
    process.exit();
}

deleteFolder(path.join(process.cwd(), modulesDirName));
process.env.npm_config_cache = cacheDirectory;
downloadSource(process.cwd());