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JavaScript Build a Simple Dynamic Site with Node.js Creating a Basic Template Engine in Node.js Reading from Files

Jonathan Leon
Jonathan Leon
18,813 Points
Posted by Jonathan Leon
Jonathan Leon
18,813 Points

Error: write after end I get this error emitted after trying to add response.end() like in the video

var Profile = require("./profile.js");
var renderer = require("./renderer.js");


// handles the http  route GET / POST i e home


function home(request,response) {





    //if the url = "/ && GET " 

  if (request.url === "/") {
        //show the search field
    response.writeHead(200, {'Content-Type': 'text/plain'});    
    renderer.view("header" , {} , response);
    renderer.view("search" , {} , response);
    renderer.view("footer" , {} , response);
    response.end();

  }
    //if the url = "// && POST " 
        //redirect to the username
}


//handles the http route get / username i.e /jonathanleo

function user(request,response) {

  var username = request.url.replace("/", "");

//if the url = "//..."

  if (username.length > 0 ) {


    response.writeHead(200, {'Content-Type': 'text/plain'});    
    renderer.view("header" , {} , response);
    response.end();

//get the JSOn from treehouse  

      var studentProfile = new Profile(username);


//on end
        studentProfile.on("end", function(profileJSON){

//show the profile

          //store the values which we need

          var values = {
            avatarUrl: profileJSON.gravatar_url ,
            username: profileJSON.profile_name ,
            badges: profileJSON.badges.length ,
            javascriptPoints: profileJSON.points.JavaScript
          }
          //simple response
    renderer.view("profile" , values , response);
    renderer.view("footer" , {} , response);
    response.end();
        });



//on error
        studentProfile.on("error", function(error) {

//show the error

          renderer.view("error" , {errorMessage: error.message} , response);
          renderer.view("search" , {} , response);
          renderer.view("footer" , {} , response);
          response.end();
       });


     }
  };




module.exports.home = home;
module.exports.user = user;
Jonathan Leon
Jonathan Leon
18,813 Points
Jonathan Leon
Jonathan Leon
18,813 Points

That's my renderer file

var fs = require("fs");


function view(templatename , values , response) {

 //read from the template files

var filecontents =  fs.readFileSync('./views/' +templatename+ ".html" );

  //insert values into the content


  //write out the contents to the response
  response.write(filecontents);





  //write out to the response





};


module.exports.view = view;
Jonathan Leon
Jonathan Leon
18,813 Points
Jonathan Leon
Jonathan Leon
18,813 Points

Okay I figured it out, I had "response.end()" after these lines of code and that was the problem

  if (username.length > 0 ) {


    response.writeHead(200, {'Content-Type': 'text/plain'});    
    renderer.view("header" , {} , response);

can someone explain me why this function ran and username.length > 0 was true when my request was just the home page? isn't "".length = 0?

Eric Moody
Eric Moody
12,373 Points

Glad you figured out the response.end(); issue.

about your secondary question about why .length > 0 evaluates to true for the home page.

Mine is doing the same thing. Were you able to figure it out? Were you running yours locally as I am?