javascript - 找不到模块 "."- webpack

Question

我正在使用 webpack 和 webpack-dev-server 重建 MEAN stack 网站的本地开发版本。我使用以下脚本来运行 webpack-dev-server:

(在 package.json 中):

"dev": "NODE_ENV=development webpack-dev-server --config webpack/webpack.dev.js --content-base src/app/--inline"

webpack.dev.js:

path = require('path');
commonConfig = require('./webpack.js');

output = {
  path: path.resolve(__dirname, 'build'),
  publicPath: 'http://localhost:8080/build/',
  filename: 'heliotrope.js'
};

module.exports = Object.assign(commonConfig, {
  output: output,
  devtool: 'source-map',
  plugins: commonConfig.plugins,
  externals: ['ws']
});

该网站构建并运行良好，但随后我收到此错误，这几乎是有史以来信息最少的事情:

error msg

查看 javascript 构建文件 heliotrope.js，看起来这可能与 websockets 有关，但我不确定，因为该模块实际上并未命名!

/***/ }),
/* 288 */
/***/ (function(module, exports, __webpack_require__) {

"use strict";
/* WEBPACK VAR INJECTION */(function(__webpack_provided_process_dot_env) {

var utils = __webpack_require__(12)
  , urlUtils = __webpack_require__(8)
  , inherits = __webpack_require__(0)
  , EventEmitter = __webpack_require__(6).EventEmitter
  , WebsocketDriver = __webpack_require__(279)
  ;

var debug = function() {};
if (__webpack_provided_process_dot_env.NODE_ENV !== 'production') {
  debug = __webpack_require__(4)('sockjs-client:websocket');
}

function WebSocketTransport(transUrl, ignore, options) {
  if (!WebSocketTransport.enabled()) {
    throw new Error('Transport created when disabled');
  }

  EventEmitter.call(this);
  debug('constructor', transUrl);

  var self = this;
  var url = urlUtils.addPath(transUrl, '/websocket');
  if (url.slice(0, 5) === 'https') {
    url = 'wss' + url.slice(5);
  } else {
    url = 'ws' + url.slice(4);
  }
  this.url = url;

  this.ws = new WebsocketDriver(this.url, [], options);
  this.ws.onmessage = function(e) {
    debug('message event', e.data);
    self.emit('message', e.data);
  };
  // Firefox has an interesting bug. If a websocket connection is
  // created after onunload, it stays alive even when user
  // navigates away from the page. In such situation let's lie -
  // let's not open the ws connection at all. See:
  // https://github.com/sockjs/sockjs-client/issues/28
  // https://bugzilla.mozilla.org/show_bug.cgi?id=696085
  this.unloadRef = utils.unloadAdd(function() {
    debug('unload');
    self.ws.close();
  });
  this.ws.onclose = function(e) {
    debug('close event', e.code, e.reason);
    self.emit('close', e.code, e.reason);
    self._cleanup();
  };
  this.ws.onerror = function(e) {
    debug('error event', e);
    self.emit('close', 1006, 'WebSocket connection broken');
    self._cleanup();
  };
}

inherits(WebSocketTransport, EventEmitter);

WebSocketTransport.prototype.send = function(data) {
  var msg = '[' + data + ']';
  debug('send', msg);
  this.ws.send(msg);
};

WebSocketTransport.prototype.close = function() {
  debug('close');
  var ws = this.ws;
  this._cleanup();
  if (ws) {
    ws.close();
  }
};

WebSocketTransport.prototype._cleanup = function() {
  debug('_cleanup');
  var ws = this.ws;
  if (ws) {
    ws.onmessage = ws.onclose = ws.onerror = null;
  }
  utils.unloadDel(this.unloadRef);
  this.unloadRef = this.ws = null;
  this.removeAllListeners();
};

WebSocketTransport.enabled = function() {
  debug('enabled');
  return !!WebsocketDriver;
};
WebSocketTransport.transportName = 'websocket';

// In theory, ws should require 1 round trip. But in chrome, this is
// not very stable over SSL. Most likely a ws connection requires a
// separate SSL connection, in which case 2 round trips are an
// absolute minumum.
WebSocketTransport.roundTrips = 2;

module.exports = WebSocketTransport;

/* WEBPACK VAR INJECTION */}.call(exports, !(function webpackMissingModule() { var e = new Error("Cannot find module \".\""); e.code = 'MODULE_NOT_FOUND'; throw e; }())))

任何帮助将不胜感激，我很困难:)

Answer 1

问题出在我的主 webpack.config 文件中，我在其中使用 ProvidePlugin 提供 NODE_ENV 变量:

new webpack.ProvidePlugin({
  'process.env': {
    'NODE_ENV': process.env.NODE_ENV
  }
})

相反，我现在像这样使用 DefinePlugin:

new webpack.DefinePlugin({
  'process.env': {
    'NODE_ENV': JSON.stringify(process.env.NODE_ENV)
  }
})