node.js - Error: Can't set headers after they are sent in node js MVC approach -


i getting following error ...

   events.js:160      throw er; // unhandled 'error' event      ^  error: can't set headers after sent.       @ serverresponse.outgoingmessage.setheader (_http_outgoing.js:357:11)       @ serverresponse.header        (c:\level3proj\node_modules\express\lib\response.js:730:10)

.. when execute following code

    var mongoose = require('mongoose');     var express = require('express');      // express router used define routes     var userrouter= express.router();      var usermodel = mongoose.model('user');     var allusers = [];     var fs = require('fs');      module.exports.controller = function(app) {       userrouter.get('/all',function(req,res) {         res.send("this route information on particular ");         usermodel.find({},function(err,allusers) {           if(err) {             res.send(err);           } else {             res.send(allusers);           }         }); // end user model       }); // end users       app.use('/users', userrouter);     } // end controller code

when load

http://localhost:3000/users/all

the result presented , @ same throwing error in console.

why getting error on console?

you send responce 2 times. first 1 here

 res.send("this route information on particular ");

and after here

if(err) {     res.send(err); } else {     res.send(allusers); }

remove first sending , responce work


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