小编Gri*_*007的帖子

我已在 Heroku 上托管了 MERN 应用程序，但每当我在 app.js 文件中实现头盔时，都会导致此问题。

const path = require('path');
const express = require('express');
const morgan = require('morgan');
const cookieParser = require('cookie-parser');
// const cors = require('cors');
const rateLimit = require('express-rate-limit');
const helmet = require('helmet');
const mongoSanitize = require('express-mongo-sanitize');
const expressSanitizer = require('express-sanitizer');
const xss = require('xss-clean');
const hpp = require('hpp');
const compression = require('compression')

const authRouter = require('./routes/authRoutes');

const app = express();
// IMPLEMENT CORS
// app.use(cors());
// app.options('*', cors());
app.use((req, res, next) => {
   res.header('Access-Control-Allow-Origin', '*');
   res.header( …