NodeJS module loader

node_module_loader.js

function NativeModule(id) {
  this.filename = id + '.js';
  this.id = id;
  this.exports = {};
  this.loaded = false;
}

NativeModule._source = process.binding('natives');
NativeModule._cache = {};

NativeModule.require = function(id) {
  if (id == 'native_module') {
    return NativeModule;
  }
  
  var cached = NativeModule.getCached(id);
  if (cached) {
    return cached.exports;
  }

  if (!NativeModule.exists(id)) {
    throw new Error('No such native module ' + id);
  }

  process.moduleLoadList.push('NativeModule ' + id);

  var nativeModule = new NativeModule(id);

  nativeModule.cache();
  nativeModule.compile();

  return nativeModule.exports;
};

NativeModule.getCached = function(id) {
  return NativeModule._cache[id];
};

NativeModule.exists = function(id) {
  return NativeModule._source.hasOwnProperty(id);
};

NativeModule.getSource = function(id) {
  return NativeModule._source[id];
};

NativeModule.wrap = function(script) {
  return NativeModule.wrapper[0] + script + NativeModule.wrapper[1];
};

NativeModule.wrapper = [
  '(function (exports, require, module, __filename, __dirname) { ',
  '\n});'
];

NativeModule.prototype.compile = function() {
  var source = NativeModule.getSource(this.id);
  source = NativeModule.wrap(source);
  
  var fn = runInThisContext(source, {filename: this.filename});
  fn(this.exports, NativeModule.require, this, this.filename);

  this.loaded = true;
};

NativeModule.prototype.cache = function() {
  NativeModule._cache[this.id] = this;
};