var express = require('express');
var app = express();
var fs = require("fs");
app.get('/listUsers', function (req, res) {
   fs.readFile( __dirname + "/" + "rest.json", 'utf8', function (err, data) {
       console.log( data );
       res.end( data );
   });
})
var server = app.listen(8081, function () {
  var host = server.address().address
  var port = server.address().port
  console.log("应用实例，访问地址为 http://%s:%s", host, port)

})

rest.json

{
   "user1" : {
      "name" : "mahesh",
 "password" : "password1",
 "profession" : "teacher",
 "id": 1
   },
   "user2" : {
      "name" : "suresh",
 "password" : "password2",
 "profession" : "librarian",
 "id": 2
   },
   "user3" : {
      "name" : "ramesh",
 "password" : "password3",
 "profession" : "clerk",
 "id": 3
   }
}

如有问题，可以QQ搜索群1028468525加入群聊，欢迎一起研究技术