Error Handling Best Practices
Error types, strategies, responses, and patterns.
Error Types
Input Errors
Handling: Validation, user feedback
Severity: Low
Business Errors
Handling: Graceful degradation
Severity: Medium
System Errors
Handling: Fallback, retry
Severity: High
Network Errors
Handling: Retry, timeout handling
Severity: Medium
Database Errors
Handling: Transaction rollback
Severity: High
Security Errors
Handling: Audit, block, notify
Severity: Critical
Handling Strategies
Fail gracefully with message
Provide fallback behavior
Log error with context
Notify appropriate parties
Retry for transient errors
Validate inputs early
Use error boundaries
Centralize error handling
Response Actions
Display message
When: User-facing, recoverable
Fallback value
When: Non-critical failure
Retry operation
When: Transient/network error
Redirect flow
When: Critical, alternative path
Stop operation
When: Unrecoverable, safety
Alert team
When: System/security critical
Implementation Patterns
Try-catch blocks
Error boundaries (React)
Global error handler
Promise rejection handling
Async error propagation
Error wrapping/classification
Error Handling Checklist
1. Identify possible error sources. 2. Classify by type and severity. 3. Define handling strategy per type. 4. Implement error capture. 5. Provide user feedback. 6. Log with context for debugging. 7. Set up alerts for critical errors. 8. Test error scenarios. 9. Document error codes/messages. 10. Review handling regularly. Error handling = robust software. Expect failures, plan responses. User experience matters. Log for debugging. Security and safety critical. Test the unhappy paths."