Question

在使用ES6语法在expressJS中导出类时，我遇到了一个问题。我的项目是带有Express JS服务器的Vue CLI项目。

要在ES5中转换快速服务器，我在启动它时将使用以下脚本：

nodemon ./server/index.js --exec babel-node --presets @babel/preset-env

在我尝试导出一个类之前，它运行良好。

class ErrorHandler extends Error {
    constructor(statusCode, message) {
        super(statusCode, message)

        this.statusCode = statusCode
        this.message = message
    }
}

const handleError = (err, res) => {
    if (!err.statusCode) err.statusCode = 500 // Sets a generic server error status code if none is part of the error
    const { statusCode, message } = err
    res.status(statusCode).json({
        status: "error",
        statusCode,
        message
    })
}

export{
    ErrorHandler,
    handleError
}

这段代码将失败，并返回以下错误：

export default function _classCallCheck(instance, Constructor) {
^^^^^^

SyntaxError: Unexpected token export
    at Module._compile (internal/modules/cjs/loader.js:723:23)
    at Module._compile (C:\Users\Romain\Documents\Developement\projector\node_modules\pirates\lib\index.js:99:24)
    at Module._extensions..js (internal/modules/cjs/loader.js:789:10)
    at Object.newLoader [as .js] (C:\Users\Romain\Documents\Developement\projector\node_modules\pirates\lib\index.js:104:7)
    at Module.load (internal/modules/cjs/loader.js:653:32)
    at tryModuleLoad (internal/modules/cjs/loader.js:593:12)
    at Function.Module._load (internal/modules/cjs/loader.js:585:3)
    at Module.require (internal/modules/cjs/loader.js:692:17)
    at require (internal/modules/cjs/helpers.js:25:18)
    at Object.<anonymous> (C:\Users\Romain\Documents\Developement\projector\server\helpers\error.js:10:47)

我尝试删除handleError函数，但仍无法正常工作，但是当我尝试删除ErrorHandler类时，一切都很好，因此它必须来自该类。

我是Node js和babel的新手，经过全部研究，我找不到问题所在。

更新这是package.json

{
  "version": "0.1.0",
  "private": true,
  "scripts": {
    "serve": "vue-cli-service serve",
    "build": "vue-cli-service build",
    "server": "nodemon ./server/index.js --exec babel-node --presets @babel/preset-env"
  },
  "dependencies": {
    "axios": "^0.19.0",
    "bulma": "^0.7.5",
    "connect-history-api-fallback": "^1.6.0",
    "core-js": "^2.6.5",
    "express": "^4.17.1",
    "express-session": "^1.16.2",
    "mongodb": "^3.3.2",
    "passport": "^0.4.0",
    "passport-local": "^1.0.0",
    "vue": "^2.6.10",
    "vue-router": "^3.0.3",
    "vuex": "^3.0.1"
  },
  "devDependencies": {
    "@babel/node": "^7.5.5",
    "@babel/preset-env": "^7.5.5",
    "@vue/cli-plugin-babel": "^3.10.0",
    "@vue/cli-service": "^3.10.0",
    "node-sass": "^4.12.0",
    "nodemon": "^1.19.1",
    "sass-loader": "^7.2.0",
    "vue-template-compiler": "^2.6.10"
  }
}

还有babel.config.js：

module.exports = {
  presets: [
    '@vue/app',
  ]
}

Babel与Vue CLI和Express JS-导出类时意外导出令牌

0 个答案: