Question

我正在尝试让我的Node项目与Webpack和Babel一起使用。当我尝试执行npm run server时，我目前正在遇到此问题。作为文字：

(node:13340) UnhandledPromiseRejectionWarning: TypeError: Cannot read property 'default' of undefined
    at C:\Users\1silv\OneDrive\Documents\Senior Project\Sage\server.js:106608:67
    at process._tickCallback (internal/process/next_tick.js:68:7)
(node:13340) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 1)
(node:13340) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.
(node:13340) UnhandledPromiseRejectionWarning: TypeError: Cannot read property 'default' of undefined
    at C:\Users\1silv\OneDrive\Documents\Senior Project\Sage\server.js:106608:67
    at process._tickCallback (internal/process/next_tick.js:68:7)
(node:13340) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 2)
webpack built 0d416d43c5c5733e2a92 in 5978ms
× ｢wdm｣: Hash: 0d416d43c5c5733e2a92
Version: webpack 4.0.0
Time: 5978ms
Built at: 3/21/2019 4:11:26 PM
    Asset      Size  Chunks                    Chunk Names
server.js  25.9 MiB     app  [emitted]  [big]  app
Entrypoint app [big] = server.js
[./node_modules/ejs/lib/ejs.js] 26 KiB {app} [built] [2 warnings]
[./node_modules/google-auth-library/build/src/index.js] 1.67 KiB {app} [built]
[./node_modules/mariadb/promise.js] 938 bytes {app} [built]
[./node_modules/moment/moment.js] 147 KiB {app} [built]
[./node_modules/plaid/lib/plaid.js] 492 bytes {app} [built]
[./node_modules/webpack-dev-middleware/index.js] 2.32 KiB {app} [built]
[./node_modules/webpack/lib/webpack.js] 7.71 KiB {app} [built]
[./server2.js] 26.3 KiB {app} [built]
[./webpack.config.js] 858 bytes {app} [built]
[child_process] external "child_process" 42 bytes {app} [built]
[fs] external "fs" 42 bytes {app} [built]
[http] external "http" 42 bytes {app} [built]
[https] external "https" 42 bytes {app} [built]
[util] external "util" 42 bytes {app} [built]
   [0] multi ./server2.js 28 bytes {app} [built]
    + 1998 hidden modules

这是它引起错误的行：

/***/ "./node_modules/loader-runner/lib/loadLoader.js":
/*!******************************************************!*\
  !*** ./node_modules/loader-runner/lib/loadLoader.js ***!
  \******************************************************/
/*! no static exports found */
/***/ (function(module, exports, __webpack_require__) {

var LoaderLoadingError = __webpack_require__(/*! ./LoaderLoadingError */ "./node_modules/loader-runner/lib/LoaderLoadingError.js");

module.exports = function loadLoader(loader, callback) {
    if(true) {
        __webpack_require__("./node_modules/loader-runner/lib lazy recursive")(loader.path).catch(callback).then(function(module) {
            loader.normal = typeof module === "function" ? module : module.default; // <-----This is the line
            loader.pitch = module.pitch;
            loader.raw = module.raw;
            if(typeof loader.normal !== "function" && typeof loader.pitch !== "function") {
                return callback(new LoaderLoadingError(
                    "Module '" + loader.path + "' is not a loader (must have normal or pitch function)"
                ));
            }
            callback();
        });
    } else { var retry, module; }
};

运行npx webpack仅会产生一系列警告，但是当我运行npm run server时，它会给出相同的警告和一系列错误，如下所示：所有../../都使我想知道它是否正在尝试使用全局npm软件包，但是我想我已经摆脱了所有这些软件包。

它也不能编译我自己的.js文件：我可以确认文件index.js在该文件夹中。

这是我的webpack.config.js文件：

const path = require('path');
const webpack = require('webpack');

module.exports = {
    target: 'node',
    mode: 'development',
    entry: {
        app: ['./server2.js']
    },
    devtool: 'inline-source-map',
    devServer: {
        contentBase: './',
        hot: true
    },
    plugins: [
        new webpack.HotModuleReplacementPlugin()
    ],
    output: {
        filename: 'server.js',
        path: path.resolve(__dirname, './'),
        publicPath: '/'
    },
    module: {
        rules: [
            {
                test: '/\.js$/',
                exclude: /node_modules/,
                use: {
                    loader: 'babel-loader',
                    options: {
                        presets: ['@babel/preset-env']
                    }
                }
            }
        ]
    }
}

这里是.babelrc：

{
    "presets": [
        [
            "@babel/preset-env",
            {
                "targets": {
                    "node": true
                }
            }
        ]
    ]
}

这是package.json：

{
  "name": "sage-savings",
  "version": "0.0.1",
  "description": "An app for easy budgeting.",
  "main": "webpack.config.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "watch": "webpack --watch",
    "build": "webpack --config webpack.config.js",
    "server": "node server.js",
    "start": "webpack-dev-server --open"
  },
  "author": "Dakota Dalton",
  "repository": "https://github.com/1silvertiger/Sage",
  "license": "ISC",
  "dependencies": {
    "@types/express": "^4.16.1",
    "aws-sdk": "^2.422.0",
    "body-parser": "^1.18.3",
    "config": "^3.0.1",
    "cors": "^2.8.5",
    "ejs": "^2.6.1",
    "express": "4.16.x",
    "express-session": "^1.15.6",
    "google-auth-library": "^3.1.0",
    "mariadb": "^2.0.3",
    "moment": "^2.24.0",
    "mysql": "^2.16.0",
    "plaid": "^2.15.0"
  },
  "devDependencies": {
    "@babel/core": "^7.4.0",
    "@babel/preset-env": "^7.4.1",
    "ajv": "^6.10.0",
    "babel-loader": "^8.0.0-beta.0",
    "typescript": "^3.3.3333",
    "webpack": "^4.0.0",
    "webpack-cli": "^3.2.3",
    "webpack-dev-middleware": "^3.6.1",
    "webpack-hot-middleware": "^2.24.3"
  }
}

目前，我不确定是什么原因导致了错误。

编辑：我运行npm install -D babel-loader @babel/core @babel/preset/env webpack重新安装了所有软件包，并在loaderLoader.js软件包中按this commit在loader-runner中注释了有问题的代码。顶部的错误现在消失了，但是底部的所有错误仍然存在。到目前为止，服务器运行良好。我有一个repo on GitHub，它将重现该错误。尝试npm run build，然后尝试npm run server。

TypeError：无法读取未定义的属性“默认”

0 个答案: