rails-error-handling

Implement error handling for Rails APIs by adding rescue_from handlers in ApplicationController to catch exceptions and return structured JSON responses. Define custom error classes to distinguish between domain and system errors, then map each exception type to an appropriate HTTP status code and error payload with descriptive messaging.

Handle validation errors in Rails by centralizing rescue logic in your controllers and service objects. Capture validation failures, extract error messages, and return user-friendly JSON responses that include field-level details and actionable guidance, enabling clients to display errors precisely.

Set up contextual logging by capturing error metadata—stack traces, request context, and user information—alongside exception handling. Centralized logging routes all errors through a consistent format, enabling monitoring tools to aggregate failures and support root-cause analysis across your Rails application.

Yes. Implement recovery patterns for background jobs by defining rescue blocks that capture job failures, log errors with context, and determine retry logic or dead-letter handling. This prevents silent failures and ensures visibility into async task health.

Domain errors represent expected, business-logic failures (e.g., invalid user input), while system errors indicate unexpected infrastructure issues (e.g., database unavailability). Distinguishing them in custom error classes enables different handling strategies: domain errors return user-friendly messages; system errors trigger alerts and retries.

No specific version requirement. The rescue_from mechanism and JSON response patterns work across modern Rails versions. The approach relies on standard Rails controller callbacks and service object patterns, making it compatible with Rails 5.0 and later.