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Question 87 of 100
Error Handling & Debugging
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Q87: What are Common API Errors, and How Do You Troubleshoot Them?
🚨Core Concept
What are Common API Errors, and How Do You Troubleshoot Them?
Key Takeaways & Architecture Summary
- ✓HTTP 400 (Bad Request): Verify request syntax, content-types, and validation.
- ✓HTTP 401 (Unauthorized): Check authentication headers and token expiration.
- ✓HTTP 403 (Forbidden): Verify user privileges and scope configurations.
- ✓HTTP 500 (Internal Error): Inspect server-side crash logs and databases.
Direct Answer Summary
Common API errors are classified by HTTP status code groups. Troubeshooting involves checking the status code, verifying that the client payload matches the server's schema expectations (400), confirming access credentials (401/403), or inspecting backend logs when encountering server-side failures (500).
⚠️ Senior Engineering Warning (Red Flag)
Avoid changing code without checking the logs first. When an API returns a 500 error, changing your client script will not fix it; you must inspect the backend server logs to find the root exception.
💡 STAR Architectural Explanation & Pro Tip
Using structured error responses with custom sub-codes (e.g. ERROR_CODE: "INSUFFICIENT_FUNDS") helps client applications handle errors gracefully, rendering targeted messages to the user.
RestAssuredTest.java
Rest-Assured + Java// Assert response code structures in Postman
pm.test("Response indicates client error", function () {
pm.expect(pm.response.code).to.be.within(400, 499);
});