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JavaScript Build a Simple Dynamic Site with Node.js Handling Routes in Node.js Populating User Information

ERR_STREAM_WRITE_AFTER_END when hosting locally.

So, I got to the end of this video, and when I run the server it works, when I open the page it works, when I put the profile to an invalid one it works, but if it's a valid profile, I get the following error:

Server running at http:
      throw er; // Unhandled 'error' event

Error [ERR_STREAM_WRITE_AFTER_END]: write after end
    at write_ (_http_outgoing.js:572:17)
    at ServerResponse.write (_http_outgoing.js:567:10)
    at Profile.<anonymous> (D:\Documents\scripts\Build a Simple Dynamic Site with Node.JS\stage_1_video_3\router.js:38:22)
    at Profile.emit (events.js:182:13)
    at IncomingMessage.<anonymous> (D:\Documents\scripts\Build a Simple Dynamic Site with Node.JS\stage_1_video_3\profile.js:38:36)
    at IncomingMessage.emit (events.js:187:15)
    at endReadableNT (_stream_readable.js:1094:12)
    at process._tickCallback (internal/process/next_tick.js:63:19)
Emitted 'error' event at:
    at writeAfterEndNT (_http_outgoing.js:634:7)
    at process._tickCallback (internal/process/next_tick.js:63:19)

The code of my router.js is the same as in the video, I even tried copying and pasting the entire "finished" version of the code into my code to make sure I had zero typing mistakes. The app.js is also the same, excepting the port number I'm using and the text that gets output by the console.log command.

var router = require("./router.js");
// Problem: Simple way to look at user's badget count and JS points from browser
// Solution: Use node.js to performe profile lookups and server our template via HTTP

//1. Create a web server
var http = require('http');
http.createServer(function (request, response){
    router.home(request, response);
    router.user(request, response);
console.log('Server running at http:');

//2. Function that handles reading of files and merge in values
    //Read from file and get string
        //merge values into string
var Profile = require("./profile.js");
//1. Handle HTTP route GET / and POST / i.e. Home
function home(request, response){
    //if url === "/" && GET
    if (request.url === "/"){
        //show search
        response.writeHead(200, {'Content-Type': 'text/plain'});
        //response.end('Hello world!\n');
    //if url === "/" && POST
        //redirect to username
//2. Handle HTTP route GET /:username i.e /chalkers
function user(request, response){
    //if URL == "/...."
    var username = request.url.replace("/", "");
    if(username.length > 0){
        response.writeHead(200, {'Content-Type': 'text/plain'});

        //get JSON from Treehouse
        var studentProfile = new Profile(username);
         //on "end"
        studentProfile.on("end", function(profileJSON){
            //Show profile

            //store values which we need
            var values = {
                avatarUrl: profileJSON.gravatar_url,
                username: profileJSON.profile_name,
                badges: profileJSON.badges.length,
                javascriptPoints: profileJSON.points.JavaScript
            //Simple response
            response.write(values.username + " has " + values.badges + " badges.\n"); 
        //on "error"               
        studentProfile.on("error", function(error){
            //show error
            response.write(error.message + "\n");


module.exports.home = home;
module.exports.user = user;

Honestly, I have no clue what could be causing this. Any guesses?

3 Answers

Adam Beer
Adam Beer
11,314 Points

Interesting issue. Because I tried your code and it works fine to me. I saw you use the server, but maybe this is the bug. Stop the server, then restart. What happend?

I tried that, yeah, even uninstalled Node.js v10 and installed v8 under recommendation from someone and it still crashes. I am so confused.

Matt Davis
Matt Davis
13,372 Points

I'm getting the same error did you ever figure this out?

It works fine on my end. All I did was change the server to the local host. But it shouldn't have changed anything relating to the error message.

var http = require('http');
http.createServer(function (request, response){
    router.home(request, response);
    router.user(request, response);
}).listen(3000, '', "");
console.log('Server running at');