小编Joh*_*obi的帖子

当我在本地运行服务器时，它工作得很好但是一旦我将其上传到 vercel，我就会收到类似 polling-xhr.js:202 GET https://giphy-chat-server.vercel.app/socket.io/?EIO=的错误4&transport=polling&t=NQ03j3c&sid=H_PHDh9-4UKRVGTVAAAC 400 与 'wss://giphy-chat-server.vercel.app/socket.io/?EIO=4&transport=websocket&sid=k-Sex1ZKmrQQFoSKAAAA' 的 WebSocket 连接失败：WebSocket 握手期间出错：意外的响应代码：400 我已经尝试了很多解决方案，但没有一个有效......我无法找出问题所在。如果得到答复，我会很高兴。谢谢

const express = require("express");

const app = express();
const http = require("http");
const path = require("path");
var server = http.createServer(app);
const io = require("socket.io")(server, {
  cors: {
    origin: "*",
    credentials: true,
    methods: ["GET", "POST"],
  },
});
const { MONGODB_URI } = require("./config");
const port = process.env.PORT || 8000;
const Message = require("./message_model");
const mongoose = require("mongoose");
mongoose
  .connect(MONGODB_URI, {
    useNewUrlParser: true,
    useUnifiedTopology: true,
    useFindAndModify: false,
  })
  .then((result) …