urlsession-code-review

URLSession Code Review Quick Reference Topic Reference Async/Await async-networking.md Requests request-building.md Errors error-handling.md Caching caching.md Review Checklist Response Validation HTTP status codes validated - URLSession does NOT throw on 404/500 Response cast to HTTPURLResponse before checking status Both transport errors (URLError) and HTTP errors handled Memory & Resources Downloaded files moved/deleted (async API doesn't auto-delete) Sessions with delegates call finishTasksAndInvalidate() Long-running tasks use [weak self] Stored Task references cancelled when appropriate Configuration timeoutIntervalForResource set (default is 7 days!) URLCache sized adequately (default 512KB too small) Sessions reused for connection pooling Background Sessions Unique identifier (especially with app extensions) File-based uploads (not data-based) Delegate methods used (not completion handlers) Security No hardcoded secrets (use Keychain) Header values sanitized for CRLF injection Query params via URLComponents (not string concat) Output Format

Critical

1. [FILE:LINE] Missing HTTP status validation
2. Issue: 404/500 responses not treated as errors
3. Fix: Check httpResponse.statusCode is 200-299