现在 Mongoose 编译后无法覆盖模型

Question

我正在使用 MongoDB Atlas 来托管数据库并使用此无服务器功能查询数据：

import { NextApiRequest, NextApiResponse } from "next";

// models
import { Section } from "../../../models/Section";

// db connection
import { useDatabase } from "../../../middleware/useDatabase";

async function find(req: NextApiRequest, res: NextApiResponse) {
  const { content } = req.query;
  const response = await Section.find({ contentType: content });
  res.send(response);
}

export default useDatabase(find);

中间件useDatabase是这样配置的：

import * as mongoose from "mongoose";
import { NextApiRequest, NextApiResponse } from "next";

export const useDatabase = handler => async (req: NextApiRequest, res: NextApiResponse) => {
  if (mongoose.connections[0].readyState) return handler(req, res);
  // Using new database connection
  await mongoose.connect(process.env.MONGODB_URI, {
    useNewUrlParser: true,
    useFindAndModify: false,
    useUnifiedTopology: true
  });

  return handler(req, res);
}

我第一次执行查询对 api 进行提取，效果很好，然后如果我编辑一些代码，保存它并 now dev 重新编译代码，当我再次执行查询时出现此错误：

MongooseError [OverwriteModelError]: Cannot overwrite `Section` model once compiled.
    at new OverwriteModelError (/home/andres/Documents/shooter-app/node_modules/mongoose/lib/error/overwriteModel.js:20:11)
    at Mongoose.model (/home/andres/Documents/shooter-app/node_modules/mongoose/lib/index.js:521:13)
    at Module../models/Section.ts (/home/andres/Documents/shooter-app/.next/server/static/development/pages/api/sections/[content].js:154:63)
    at __webpack_require__ (/home/andres/Documents/shooter-app/.next/server/static/development/pages/api/sections/[content].js:23:31)
    at Module../pages/api/sections/[content].ts (/home/andres/Documents/shooter-app/.next/server/static/development/pages/api/sections/[content].js:198:73)
    at __webpack_require__ (/home/andres/Documents/shooter-app/.next/server/static/development/pages/api/sections/[content].js:23:31)
    at Object.3 (/home/andres/Documents/shooter-app/.next/server/static/development/pages/api/sections/[content].js:233:18)
    at __webpack_require__ (/home/andres/Documents/shooter-app/.next/server/static/development/pages/api/sections/[content].js:23:31)
    at /home/andres/Documents/shooter-app/.next/server/static/development/pages/api/sections/[content].js:91:18
    at Object.<anonymous> (/home/andres/Documents/shooter-app/.next/server/static/development/pages/api/sections/[content].js:94:10)
    at Module._compile (internal/modules/cjs/loader.js:955:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:991:10)
    at Module.load (internal/modules/cjs/loader.js:811:32)
    at Function.Module._load (internal/modules/cjs/loader.js:723:14)
    at Module.require (internal/modules/cjs/loader.js:848:19)
    at require (internal/modules/cjs/helpers.js:74:18)
    at DevServer.handleApiRequest (/home/andres/Documents/shooter-app/node_modules/next/dist/next-server/server/next-server.js:420:28)
    at async Object.fn (/home/andres/Documents/shooter-app/node_modules/next/dist/next-server/server/next-server.js:350:37)
    at async Router.execute (/home/andres/Documents/shooter-app/node_modules/next/dist/next-server/server/router.js:42:32)
    at async DevServer.run (/home/andres/Documents/shooter-app/node_modules/next/dist/next-server/server/next-server.js:468:29) {
  message: 'Cannot overwrite `Section` model once compiled.',
  name: 'OverwriteModelError'
}

我该如何解决？谢谢！

Answer 1

当开发服务器在热模块替换期间尝试重新编译您的模型时会发生这种情况。

您可以通过更改代码以在导出模型时检查模型是否已经编译来防止这种情况发生。

export default mongoose.models['Section'] || mongoose.model('Section', SectionSchema);