Implementation of Standardized HTTP Response and Error System

[dinhoSilwa]

Description

Implement a complete and standardized response and error handling system for the Certify API, following RESTful API development best practices.

Phase 1: Response Schema Structure

Tasks:

• Create Pydantic schemas for standardized responses
• Implement SuccessResponse with generics for strong typing
• Implement ErrorResponse with specific error codes
• Create PaginatedResponse for endpoints with pagination
• Add automatic timestamp to all responses

Expected Response Models:

Success:

{
  "success": true,
  "message": "Operation completed successfully",
  "timestamp": "2024-01-15T10:30:00.000Z",
  "data": {
    "resource": { ... }
  }
}

Error:

{
  "success": false,
  "message": "Friendly error description",
  "timestamp": "2024-01-15T10:30:00.000Z",
  "error_code": "RESOURCE_NOT_FOUND",
  "details": {
    "field": "additional value for debug"
  }
}

Phase 2: Custom Exception System

Tasks:

• Create base class APIException for all exceptions
• Implement specific exceptions:
  • NotFoundException (404)
  • ValidationException (422)
  • AuthenticationException (401)
  • AuthorizationException (403)
  • ConflictException (409)
  • InternalServerException (500)
• Configure global handlers for each exception type
• Ensure all exceptions return the standardized format

Phase 3: Repository Layer Update

Tasks:

• Refactor AuthRepository to use the new exceptions
• Refactor CertificateRepository to use the new exceptions
• Replace generic exceptions with specific ones
• Consistently validate ObjectId in all queries
• Improve error messages to be more descriptive

Phase 4: Service Layer Update

Tasks:

• Update AuthService to propagate specific exceptions
• Update CertificateService to use the new pattern
• Remove redundant error handling
• Ensure services return only correct response models

Phase 5: Routes Refactoring

Tasks:

• Update all routes in auth_routes.py
• Update all routes in certificate_routes.py
• Remove unnecessary try-catch blocks from endpoints
• Ensure all responses use SuccessResponse.create()
• Update response_model annotations in decorators

Phase 6: FastAPI Configuration

Tasks:

• Register all exception handlers in main.py
• Configure CORS middleware if necessary
• Update automatic documentation to reflect new schemas
• Test all exception handlers

Phase 7: Validation and Testing

Tasks:

• Test all success scenarios
• Test all error scenarios
• Validate JSON response formats
• Verify correct HTTP status codes
• Test pagination if applicable
• Validate Pydantic validation error handling

Acceptance Criteria:

• All success responses follow the standardized format
• All errors return appropriate HTTP codes
• Error messages are user-friendly
• Error codes are consistent and descriptive
• Timestamp is present in all responses
• Global handlers catch all unhandled exceptions
• Swagger documentation reflects the new schemas
• No regressions in existing functionality

Expected Benefits:

• Better frontend development experience

• More efficient debugging with specific error codes

• Consistency across all API responses

• Appropriate handling of different error scenarios

• Ease of maintenance and extension