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Question 91 of 100
Error Handling & Debugging
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Q91: How Do You Troubleshoot and Handle HTTP 404 Not Found Errors?
🚨Core Concept
How Do You Troubleshoot and Handle HTTP 404 Not Found Errors?
Key Takeaways & Architecture Summary
- ✓Verify that the URL path and endpoint spelling are correct.
- ✓Check that dynamic path parameters exist in the database.
- ✓Inspect route configurations in the backend application code.
Direct Answer Summary
An HTTP 404 Not Found error indicates that the server cannot locate the requested resource. This can occur because the endpoint URL is misspelled, or the dynamic path parameter (like a user ID) does not exist in the database.
⚠️ Senior Engineering Warning (Red Flag)
Never assume a 404 error is always a client spelling mistake. If your endpoint references an ID that does not exist in the database (e.g. /users/9999), a RESTful API should return a 404.
💡 STAR Architectural Explanation & Pro Tip
Handling non-existent IDs gracefully by returning a 404 prevents application crashes, providing clean error states that the client UI can translate for the user.
PlaywrightApiTest.ts
Playwright API// Verify Not Found response in Playwright
const res = await apiContext.get('/api/v1/users/non-existent-uuid');
expect(res.status()).toBe(404);