导入Node路由时Node.js服务崩溃，求问题排查方法

问题场景 #

导入路由模块时服务崩溃，移除路由后服务正常运行，已确认路径但问题依旧。核心代码如下：

import express from "express";
import cors from "cors";
import verifyRouter from "./routes/jwtauth";

const app = express();
const port = 4500;

// Middleware
app.use(cors());
app.use(express.json());

app.use("/auth", verifyRouter);

app.listen(port, () => {
    console.log(`Server is running at http://localhost:${port}`);
});

报错信息：

Error [ERR_MODULE_NOT_FOUND]: Cannot find module 'C:\Users\DELL\Desktop\myproject\server\routes\jwtauth' imported from C:\Users\DELL\Desktop\myproject\server\index.js
Did you mean to import ../routes/jwtauth.js?
    at new NodeError (node:internal/errors:405:5)
    at finalizeResolution (node:internal/modules/esm/resolve:327:11)
    at moduleResolve (node:internal/modules/esm/resolve:946:10)
    at defaultResolve (node:internal/modules/esm/resolve:1132:11)
    at nextResolve (node:internal/modules/esm/loader:163:28)
    at ESMLoader.resolve (node:internal/modules/esm/loader:835:30)
    at ESMLoader.getModuleJob (node:internal/modules/esm/loader:424:18)
    at ModuleWrap.<anonymous> (node:internal/modules/esm/module_job:77:40)
    at link (node:internal/modules/esm/module_job:76:36) {
  code: 'ERR_MODULE_NOT_FOUND'
}

Node.js v18.18.2
[nodemon] app crashed - waiting for file changes before starting...

排查与解决步骤 #

• 补全文件扩展名：Node.js ESM模式下必须指定完整文件扩展名，不能省略.js。修改导入语句为：

  import verifyRouter from "./routes/jwtauth.js";
  

• 核对文件实际状态：
  • 确认server/routes目录下存在jwtauth.js文件，检查文件名拼写、大小写（Windows系统虽不区分，但ESM解析可能严格匹配）
  • 排除文件扩展名错误（如误命名为.jsx/.ts等）
• 确认ESM模式配置：在项目根目录的package.json中添加"type": "module"，确保Node.js将文件当作ESM模块处理：

  {
    "type": "module"
  }
  

• 验证相对路径逻辑：确认index.js位于server/目录下，./routes/jwtauth.js对应路径为server/routes/jwtauth.js，与报错中缺失扩展名的路径一致
• 检查nodemon配置：若使用nodemon，确保其未忽略routes目录文件，无路径解析相关异常配置

内容的提问来源于stack exchange，提问作者Oguogho