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Karen Shea
13,851 PointsRangeError [ERR_HTTP_INVALID_STATUS_CODE]: Invalid status code: undefined Pretty sure the issue is in cards.js.
Pretty sure the issue is in cards.js.
Here is the entirety of that file:
```const express = require('express'); const router = express.Router(); const { data } = require('../data/flashcarddata.json'); const { cards } = data;
router.get('/', (req, res) => {
const numberOfCards = cards.length;
const flashcardId = Math.floor(Math.random() * numberOfCards);
res.redirect(/cards/${flashcardId}
);
});
router.get('/:id', (req, res) => { const { side } = req.query; const { id } = req.params;
if (!side) {
res.redirect(/cards/${id}?side=question
)
}
const name = req.cookies.username;
const text = cards[id][side];
const { hint } = cards[id];
const templateData = { id, text, name };
if (side === 'question') {
templateData.hint = hint;
templateData.sideToShow = 'answer';
templateData.sideToShowDisplay = 'Answer';
} else if (side === 'answer') {
templateData.sideToShow = 'question';
templateData.sideToShowDisplay = 'Question';
}
res.render('card', templateData);
});
module.exports = router;```
2 Answers

Kevin Gates
14,855 PointsOkay, I've had to deal with this. It's requiring an HTTP status code, so I've used 302. So if you change from this:
res.redirect(/cards/${flashcardId});
to this
res.status(302).redirect(`/cards/${flashcardId}`);
it should work.
Also though, for me the behavior is different. If I'm in the sub-folder already it sometimes results in cards/cards/3...
So to get this to work localhost:3000/cards/
and localhost:3000/cards/3
to work, I need to make my code this:
const express = require('express');
const router = express.Router();
const { data } = require('../data/flashcardData.json');
const { cards } = data;
router.get('/:id', (req, res) => {
const { side } = req.query;
const { id } = req.params;
if ( !side ) {
res.status(302).redirect(`${id}?side=question`)
}
const text = cards[id][side];
const { hint } = cards[id];
const templateData = { id, text };
if (side === 'question') {
templateData.hint = hint;
templateData.sideToShow = "answer";
templateData.sideToShowDisplay = "Answer";
} else if (side === "answer") {
templateData.sideToShow = "question";
templateData.sideToShowDisplay = "Question";
}
res.render('card', templateData);
});
router.get('/', (req, res) => {
const totalCards = cards.length;
const randomCard = Math.floor(Math.random()*totalCards);
res.status(302).redirect(`${randomCard}?side=question`);
});
module.exports = router;

Marie Franklin
12,505 PointsOne problem is that you are defining side as const and later reassigning it... instead you should define side with let
let {side} = req.query;