getting RangeError [ERR_HTTP_INVALID_STATUS_CODE]: Invalid status code: undefined in express app

Question

I am getting the above error when running the following code in my express app. When I go to localhost:3000/cards.

This is in my cards.js file.

const express = require('express');
const router = express.Router();
const { data } = require('../data/flashcardData.json');
const { cards } = data;

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

module.exports = router;

This is the code in my app.js file.

const express = require('express');
const bodyParser = require('body-parser');
const cookieParser = require('cookie-parser');

const app = express();

app.use(bodyParser.urlencoded({ extended: false }));
app.use(cookieParser());

app.set('view engine', 'pug');

const mainRoutes = require('./routes');
const cardRoutes = require('./routes/cards');

app.use(mainRoutes);
app.use('/cards', cardRoutes);

app.use((req, res, next) => {
    const err = new Error('Not Found');
    err.status = 404;
    next(err);
});

app.use((err, req, res, next) => {
    res.locals.error = err;
    res.status(err.status);
    res.render('error');
});

app.listen(3000, () => {
    console.log('The application is running on localhost:3000!');
});

Any help would be appreciated. Basically, I am trying to incorporate a json file into the express app and it is coming up with this error.

Nate Anderson · Accepted Answer · 2024-05-22 16:07:20Z

24

Set a default status in your error handler middleware if error does not contain the property status. In this case we default to error code 500:

const express = require('express');
const bodyParser = require('body-parser');
const cookieParser = require('cookie-parser');

const app = express();

app.use(bodyParser.urlencoded({ extended: false }));
app.use(cookieParser());

app.set('view engine', 'pug');

const mainRoutes = require('./routes');
const cardRoutes = require('./routes/cards');

app.use(mainRoutes);
app.use('/cards', cardRoutes);

app.use((req, res, next) => {
  const err = new Error('Not Found');
  err.status = 404;
  next(err);
});

app.use((err, req, res, next) => {
  res.locals.error = err;
  //------------------------vvvvvvv added
  const status = err.status || 500;
  res.status(status);
  res.render('error');
});

app.listen(3000, () => {
  console.log('The application is running on localhost:3000!');
});

edited May 22, 2024 at 16:07

Nate Anderson

21.6k22 gold badges113 silver badges155 bronze badges

answered Mar 10, 2018 at 15:41

Korbinian Kuhn

8065 silver badges11 bronze badges

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3 Comments

Mohammed Ramadan Over a year ago

this const status = err.status || 500; helped me :) thanks a lot

Nik Over a year ago

what if err.status is something invalid (bcoz of typo) like err.status=1 or 24

Korbinian Kuhn Over a year ago

Express will throw an error and send status code 500 + message + stack. If you want to send a custom response, you have 3 options: 1. wrap res.status() in try/catch, 2. use a second error middleware , 3. validate status against the builtin http.STATUS_CODES list.

Vaibhav Yadav · Accepted Answer · 2023-05-02 20:45:53Z

2

In My Case this Happened because I haven't provided Authorization in My Request :)

answered May 2, 2023 at 20:45

Vaibhav Yadav

212 bronze badges

1 Comment

Community Over a year ago

Your answer could be improved with additional supporting information. Please edit to add further details, such as citations or documentation, so that others can confirm that your answer is correct. You can find more information on how to write good answers in the help center.

Stefan Georgiev · Accepted Answer · 2023-10-05 20:30:01Z

1

In my case I was trying to have a fallback value in my custom error class like so:

// apiError.js
class ApiError extends Error {
  constructor(message, source, statusCode) {
    super();
    this.statusCode = statusCode || 500;
    this.message = message;
    this.source = source || 'Unknown';
  }
}

But the actual problem was in the custom error middleware when the response was being send:

// apiErrorHandler.js
import logger from '../util/logger.js';

const apiErrorHandler = function (error, req, res, next) {
  if (error.source) {
    logger.error(`${error.message} ----->  ${error.source}`);
  }

  res.status(error.statusCode ?? 500).json({ // I was missing this ?? 500 as a fallback value
    status: 'error',
    statusCode: `${error.statusCode}` ?? 500,
    stack: error.stack,
  });
};

export default apiErrorHandler;

answered Oct 5, 2023 at 20:30

Stefan Georgiev

391 silver badge10 bronze badges

1 Comment

Nate Anderson Over a year ago

Similar to accepted answer, which falls back on default code value 500 using || operator.

Vikram Kumar · Accepted Answer · 2023-05-18 06:49:37Z

0

instead use res.render() if your are using ejs to create the template;

answered May 18, 2023 at 6:49

Vikram Kumar

1

1 Comment

Community Over a year ago

Your answer could be improved with additional supporting information. Please edit to add further details, such as citations or documentation, so that others can confirm that your answer is correct. You can find more information on how to write good answers in the help center.

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