Debugging_With_Copilot.md

Bugs Identified

• Weak validation:
  • No email format check.
  • No length limits on Name or Email.
  • No duplicate email check.
• No explicit handling for a null user object in validation.
• No protection against unexpected exceptions that could crash the API.

Fixes Implemented

• Added regex-based email format validation.
• Added length limits: Name ≤ 100 chars, Email ≤ 150 chars.
• Added duplicate email check (case-insensitive) returning 400 with "Email is already in use."
• Centralized validation logic in the ValidateUser method.
• Wrapped each endpoint in try/catch to handle unexpected exceptions and return HTTP 500 with a generic message.

How Copilot Streamlined Debugging

• Analyzed UsersController and highlighted validation and error-handling gaps.
• Generated the regex pattern for email validation and suggested the structure of the ValidateUser method.
• Produced updated controller code with try/catch blocks around each endpoint to prevent unhandled exceptions.
• Helped design test cases for:
  • Invalid input (missing name/email, bad email format).
  • Duplicate emails.
  • Requests for non-existent user IDs (404 handling).

As a result, the API now validates user data more robustly, handles errors gracefully, and returns clear, appropriate HTTP status codes.