Problem Details RFC 9457: Chuẩn Hóa Phản Hồi Lỗi REST

// Doi A:
{ "error": "not_found", "msg": "Don hang 42 khong ton tai" }

// Doi B:
{ "success": false, "message": "Khong tim thay", "code": 404 }

// Doi C:
{ "status": 404, "errorMessage": "Not found", "errorCode": "E004" }

HTTP/1.1 404 Not Found
Content-Type: application/problem+json

{
  "type": "https://api.olhub.org/errors/order-not-found",
  "title": "Order not found",
  "status": 404,
  "detail": "Order 42 was not found or has been deleted",
  "instance": "/api/v1/orders/42",
  "orderId": 42,
  "timestamp": "2026-06-09T08:00:00Z"
}

spring:
  mvc:
    problemdetails:
      enabled: true

// Khoi tao voi status HTTP
ProblemDetail pd = ProblemDetail.forStatus(HttpStatus.NOT_FOUND);

// Thiet lap cac truong chuan
pd.setType(URI.create("https://api.olhub.org/errors/order-not-found"));
pd.setTitle("Order not found");
pd.setDetail("Don hang 42 khong ton tai trong he thong");
pd.setInstance(URI.create("/api/v1/orders/42"));

// Bo sung cac extension member tuy bien
pd.setProperty("orderId", 42L);
pd.setProperty("timestamp", Instant.now());
pd.setProperty("requestId", MDC.get("requestId"));

@RestControllerAdvice
@Slf4j
public class GlobalExceptionHandler {

    // 1. Xu ly loi khong tim thay tai nguyen -> 404
    @ExceptionHandler(OrderNotFoundException.class)
    public ProblemDetail handleOrderNotFound(OrderNotFoundException ex, HttpServletRequest req) {
        ProblemDetail pd = ProblemDetail.forStatus(HttpStatus.NOT_FOUND);
        pd.setType(URI.create("https://api.olhub.org/errors/order-not-found"));
        pd.setTitle("Order not found");
        pd.setDetail(ex.getMessage());
        pd.setInstance(URI.create(req.getRequestURI()));
        pd.setProperty("orderId", ex.getOrderId());
        return pd;
    }

    // 2. Xu ly xung dot du lieu -> 409
    @ExceptionHandler(DuplicateOrderException.class)
    public ProblemDetail handleDuplicateOrder(DuplicateOrderException ex, HttpServletRequest req) {
        ProblemDetail pd = ProblemDetail.forStatus(HttpStatus.CONFLICT);
        pd.setTitle("Duplicate order");
        pd.setDetail(ex.getMessage());
        pd.setInstance(URI.create(req.getRequestURI()));
        return pd;
    }

    // 3. Xu ly loi validation du lieu dau vao -> 400
    @ExceptionHandler(MethodArgumentNotValidException.class)
    public ProblemDetail handleValidation(MethodArgumentNotValidException ex, HttpServletRequest req) {
        ProblemDetail pd = ProblemDetail.forStatus(HttpStatus.BAD_REQUEST);
        pd.setType(URI.create("https://api.olhub.org/errors/validation"));
        pd.setTitle("Validation failed");
        pd.setDetail("Du lieu yeu cau khong hop le");
        pd.setInstance(URI.create(req.getRequestURI()));

        List<Map<String, Object>> violations = ex.getBindingResult().getFieldErrors().stream()
            .map(err -> {
                Map<String, Object> map = new LinkedHashMap<>();
                map.put("field", err.getField());
                map.put("message", err.getDefaultMessage());
                map.put("rejectedValue", err.getRejectedValue());
                return map;
            })
            .toList();
        pd.setProperty("violations", violations);
        return pd;
    }

    // 4. Catch-all: An toan cho moi ngoai le chua luong truoc -> 500
    @ExceptionHandler(Exception.class)
    public ProblemDetail handleAllExceptions(Exception ex, HttpServletRequest req) {
        String requestId = MDC.get("requestId");
        log.error("Unhandled error: path={}, requestId={}", req.getRequestURI(), requestId, ex);

        ProblemDetail pd = ProblemDetail.forStatus(HttpStatus.INTERNAL_SERVER_ERROR);
        pd.setTitle("Internal server error");
        pd.setDetail("Da xay ra loi he thong. Vui long lien he quan tri vien.");
        pd.setInstance(URI.create(req.getRequestURI()));
        pd.setProperty("requestId", requestId);
        return pd;
    }
}

# application-prod.yml: Cau hinh an toan
server:
  error:
    include-stacktrace: never
    include-message: never
    include-binding-errors: never

@WebMvcTest(OrderController.class)
@Import(GlobalExceptionHandler.class)
class OrderExceptionHandlerTest {

    @Autowired private MockMvc mockMvc;
    @MockitoBean private OrderService orderService;

    @Test
    void whenOrderNotFound_thenReturns404ProblemDetail() throws Exception {
        when(orderService.findById(99L)).thenThrow(new OrderNotFoundException(99L));

        mockMvc.perform(get("/api/v1/orders/99"))
            .andExpect(status().isNotFound())
            .andExpect(content().contentType("application/problem+json"))
            .andExpect(jsonPath("$.status").value(404))
            .andExpect(jsonPath("$.title").value("Order not found"))
            .andExpect(jsonPath("$.detail").value("Order 99 was not found"))
            .andExpect(jsonPath("$.orderId").value(99));
    }

    @Test
    void whenInternalError_thenDoesNotLeakStackTrace() throws Exception {
        when(orderService.findById(any())).thenThrow(new RuntimeException("SQL syntax error at table users"));

        String responseBody = mockMvc.perform(get("/api/v1/orders/1"))
            .andExpect(status().isInternalServerError())
            .andExpect(content().contentType("application/problem+json"))
            .andExpect(jsonPath("$.requestId").exists())
            .andReturn().getResponse().getContentAsString();

        assertThat(responseBody).doesNotContain("SQL syntax");
        assertThat(responseBody).doesNotContain("users");
        assertThat(responseBody).doesNotContain("stackTrace");
    }
}