← Challenges
The 200 OK That's Actually An Error
Description
Your frontend POSTs to /api/subscribe and gets 200 OK. The UI shows "Subscribed! 🎉" But users never receive emails. Turns out the backend always returns 200 — even when the email provider rejects the request. The error is hidden inside the response body, which the frontend never checks.
What is the value of provider_response.status that indicates the subscription actually failed?
Trust but verify. Especially HTTP 200s.
Input Data
```javascript
// Backend: src/routes/subscribe.js
app.post('/api/subscribe', async (req, res) => {
try {
const { email } = req.body;
const result = await emailService.addSubscriber(email);
res.status(200).json({
success: true,
message: 'Subscription processed',
provider_response: result
});
} catch (err) {
// Even errors return 200 😱
res.status(200).json({
success: true,
message: 'Subscription processed',
provider_response: { status: 'queued' }
});
}
});
```
```json
// Response from a failing subscription:
{
"success": true,
"message": "Subscription processed",
"provider_response": {
"id": null,
"status": "rejected",
"reason": "invalid_domain",
"email": "user@typomail.con"
}
}
```
```javascript
// Frontend — only checks top-level "success":
.then(data => {
if (data.success) showToast('Subscribed! 🎉');
});
```Solve This Challenge
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