🚨 Centralized Exception Handling in Rails ApplicationController

✨ Purpose and Benefits

Centralized exception handling in a Ruby on Rails application streamlines error management by:

• Improving consistency: Ensures all API errors follow a predictable structure.
• Reducing duplication: Eliminates the need for repetitive error handling logic across controllers.
• Simplifying debugging: Logs detailed error information in one place.
• Enhancing client experience: Returns clean, informative JSON error messages to API consumers.

⚙️ How It Works

This implementation introduces a top-level rescue mechanism inside ApplicationController, intercepting all unhandled StandardError exceptions via the handle_api_exception method.

Depending on the error type, the exception is passed to specialized methods that determine the appropriate status code and message. If the environment is production, a generic message is pulled from the i18n configuration to avoid leaking internal error details.

All JSON responses are rendered in a consistent format using helper methods like render_error, render_notice, and render_json.

🔧 Key Methods Added or Modified

handle_api_exception(exception)

Top-level handler for all StandardError exceptions. Delegates to more specific methods based on exception type.

handle_database_level_exception(exception)

Handles low-level DB exceptions with a generic response.

handle_generic_exception(exception, status = :internal_server_error)

Logs the exception unless in test environment and returns a generic message using i18n in production (t("generic_error")).