Error Handling & Standardized Response Flow

Global pipeline for intercepting failures, mapping them to business-friendly status codes, and ensuring diagnostic traceability.

Sequence

Error Mapping Strategy

The system uses a centralized mapping logic to ensure consistency across all endpoints:

Exception Type	HTTP Status	Business Error Code
UserFriendlyException	Dynamic (Mapped)	Dynamic (Mapped)
KeyNotFoundException	404 Not Found	IA.NOT_FOUND
ValidationException	400 Bad Request	IA.BAD_REQUEST
UnauthorizedAccessException	401 Unauthorized	IA.UNAUTHORIZED
System.Exception	500 Internal Error	IA.GENERAL_ERROR

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Response Structure

All errors follow the same JSON schema to allow the frontend to display uniform error alerts:

{
  "error": {
    "code": "InventoryAlert.NOT_FOUND",
    "message": "Symbol 'XYZ' is not recognized."
  },
  "correlationId": "CID-123",
  "timestamp": "2026-05-04T12:00:00Z"
}

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Logic Highlights

Feature	Detail
Diagnostic Trace	Every error response includes the correlationId, allowing users to provide a reference for support logs.
User Friendly Messages	UserFriendlyException allows services to pass safe, translated messages to the UI while keeping technical details in logs.
Validation Integration	Automatically captures and formats FluentValidation failures into the standard error schema.
Transaction Rollback	Since the middleware catches exceptions at the top level, incomplete DB transactions are naturally rolled back by the Unit of Work.