小编Nia*_*ush的帖子

//test1.js
let http = require("http");
let express = require("express");
let app = express();

let middle = require("./test2.js");
app.use(middle);

app.use(function(req, res, next) {
  next();
});
http.createServer(app).listen(80);

//test2.js
module.exports = function(req, res, next) {
  console.log("middle");
  next();
};