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JavaScript Express Basics Parameters, Query Strings, and Modularizing Routes Using Data and Route Parameters

Brian Patterson
Brian Patterson
19,588 Points
Posted by Brian Patterson
Brian Patterson
19,588 Points

getting this error RangeError [ERR_HTTP_INVALID_STATUS_CODE]: Invalid status code: undefined when going to cards.

I am running the following code in the cards.js file.

const express = require('express');
const router = express.Router();
const { data } = require('../data/flashcardData.json');
//the above is the same as:
//const  data  = require('../data/flashcardData.json').data;
const cards = data.cards;

router.get('/', (req, res) => {
  res.render('card', {
    prompt: cards[0].question,
    hint: cards[0].hint
  });
});

module.exports = router;

and I am getting the above error. What does it mean? Below is it the error code in the console.

at ServerResponse.writeHead (_http_server.js:197:11)
    at ServerResponse._implicitHeader (_http_server.js:188:8)
    at write_ (_http_outgoing.js:644:9)
    at ServerResponse.end (_http_outgoing.js:767:5)
    at ServerResponse.send (/Users/briankaty1/Dropbox/JavaScript/flashcards/node_modules/express/lib/response.js:221:10)
    at done (/Users/briankaty1/Dropbox/JavaScript/flashcards/node_modules/express/lib/response.js:1004:10)
    at Object.exports.renderFile (/Users/briankaty1/Dropbox/JavaScript/flashcards/node_modules/pug/lib/index.js:422:12)
    at View.exports.__express [as engine] (/Users/briankaty1/Dropbox/JavaScript/flashcards/node_modules/pug/lib/index.js:465:11)
    at View.render (/Users/briankaty1/Dropbox/JavaScript/flashcards/node_modules/express/lib/view.js:135:8)
    at tryRender (/Users/briankaty1/Dropbox/JavaScript/flashcards/node_modules/express/lib/application.js:640:10)

2 Answers

Alina Bylkova
Alina Bylkova
6,862 Points
Alina Bylkova
Alina Bylkova
6,862 Points

Check your pug file for example if you still pass all the required variables, for example

if you comment out colors variable, pug cannot create list of colors and in my case failed with ERR_HTTP_INVALID_STATUS_CODE

res.render('card', {
    prompt: "Who is buried in Grant's tomb?",
    hint: 'Think about whose tomb it is.',
    //colors,
  });

extends layout.pug

block content
  section#content
//    ul
//      each color in colors
//        li= color
    h2= prompt
    if hint
      p
        i Hint: #{hint}
    else
      p (There is no hint.)
Michael Kilcorse
seal-mask
PLUS
.a{fill-rule:evenodd;}techdegree seal-36
Michael Kilcorse
Full Stack JavaScript Techdegree Graduate 17,643 Points
Michael Kilcorse
.a{fill-rule:evenodd;}techdegree seal-36
Michael Kilcorse
Full Stack JavaScript Techdegree Graduate 17,643 Points

What URL are you typing into your browser? I was getting this error because I accidentally typed localhost:3000/cards/id into my browser instead of localhost:3000/cards/1

But yeah, I would check your URL path

Michael Cook
.a{fill-rule:evenodd;}techdegree seal-36
Michael Cook
Full Stack JavaScript Techdegree Graduate 28,975 Points

I am getting the same error but my url is correct. It would be really nice if you responded saying how you fixed it for the benefit of others.