处理OpenFeign调用的webservices的异常

Question

我有几个微服务，我用openfeign来调用不同的微服务。全局应用程序的入口点名为dispatcher-ws。他的作用是根据有效载荷分派呼叫。

作为条目，我确实有以下有效载荷：

{
   "operation": "signature",
   "clientId": "abcdef",
   ...
   "pdfDocument": "JVBERi0xLjMNCiXi48/TDQoNCjEg..."
}

我有一个名为签名-ws的微服务，可以处理pdf签名。到现在为止还好。我用这种方式实现了我的客户：

@FeignClient(name="signature-ws", decode404 = true, url = "http://localhost:8080/signature-ws/api")
public interface SignatureClient {    
    @PostMapping("/signature")
    Map<String, Object> signDocument(RequestDto request) throws AppServiceException;
}

在我的服务层中，我尝试根据操作值进行调用：

@Service
public class RequestServiceImpl implements DispatchService {
    private final RequestRepository requestRepository;
    private final SignatureClient signatureClient;
    private final Resilience4JCircuitBreakerFactory circuitBreakerFactory;


    @Autowired
    public DispatchServiceImpl(RequestRepository requestRepository,
                               SignatureClient signatureClient,
                               Resilience4JCircuitBreakerFactory circuitBreakerFactory) {
        this.requestRepository = requestRepository;
        this.signatureClient = signatureClient;
        this.circuitBreakerFactory = circuitBreakerFactory;
    }


@Override
public RequestDto handleRequest(RequestDto request) {
    RequestDto returnValue = new RequestDto();
    // if not initialized, throw null pointer exception...
    returnValue.setPayloads(new ArrayList<>());
    if(request.getOperation().equals("signature") {
       Resilience4JCircuitBreaker circuitBreaker = circuitBreakerFactory.create("signature");
       Supplier<Map<String, Object>> signatureResponseSupplier =
                    () -> signatureClient.signDocument(request);
       Map<String, Object> signatureResponse = circuitBreaker.run(
           signatureResponseSupplier,
           throwable -> handleException()
       );
      ...
      returnValue.getResponses().add(signatureResponse)
 
    }
    return retunValue;
}

...
private Map<String, Object> handleException() {
    Map<String, Object> returnValue = new HashMap<>();
    returnValue.put("Error", "Error rmessage ... ");
    returnValue.put("status", "Failure");
    return returnValue;
}

如果我没有在签名don服务中传递pdfDocument，我就会检索一个异常。

{
    "errorId": "Qe99DwntFrMPCAfuZfDQW1ucwNh5BK",
    "status": "ERROR",
    "operations": "signature",
    "profile": "client123456",
    "errorMessage": "PDF is missing",
    "createdAt": 1647354022127
}

我想检索异常响应，并将键值传递给handleException方法中的映射。在这个阶段，它没有返回任何东西，更糟糕的是，我确实返回了200状态。

我实现了一个管理响应返回的controllerAdvice。这个类在我的所有web服务中是相同的(我应该考虑创建一个处理所有异常的微服务.)

@ControllerAdvice(basePackages = { "com.company.app" })
public class AppExceptionsHandler {
    private final RequestContext requestContext;

    @Autowired
    public AppExceptionsHandler(RequestContext requestContext) {
        this.requestContext = requestContext;
    }

    @ExceptionHandler(value = {AppServiceException.class})
    public ResponseEntity<Object> handleAppException(AppServiceException ex,
                                                             WebRequest request) {
        // récupérer le body
        DispatchDto response = requestContext.getResponse();
        ErrorMessage errorMessage = ErrorMessage.builder()
                .errorId(response.getId())
                .status(RequestOperationStatus.ERROR.name())
                .operations(response.getOperations())
                .profile(response.getProfile())
                .errorMessage(ex.getMessage())
                .createdAt(new Date())
                .build();
        }
        return new ResponseEntity<>(errorMessage, new HttpHeaders(), HttpStatus.INTERNAL_SERVER_ERROR);
    }
}

我所期望的是在我的调度器微服务中返回相同的异常。

Answer 1

我找到了解决这个问题的办法。首先，我被一次尝试抓住了我的假装请求：

try {
    ...
    Map<String, Object> facturxResponse = 
           facturXClient.createFacturX(dispatchDto);
        ...
} catch(FeignException e) {
    System.out.println(e.getMessage());
    throw new AppServiceException(e.getMessage());
}

我注意到e.getMessage返回一个具有以下模式的字符串：

[500 Internal Server Error] during [POST] to [http://localhost:8080/my-ws/api/ws] 
[FacturXClient#createFacturX(DispatchDto)]: [{"errorId":"z3o1bE8SJrm8WGrxlpIIWe6TNf0NzR","status":"ERROR","operations":"facturx","profile":"client123456","errorMessage":"PDF is missing","createdAt":1647422337344}]

我抛出这个异常并拦截响应。

@ExceptionHandler(value = {AppServiceException.class})
public ResponseEntity<Object> handleUserServiceException(AppServiceException ex,
                                                         WebRequest request) throws JsonProcessingException {
    String input = ex.getMessage();
    String[] splitResponse = input.split(":", 4);
    ObjectMapper mapper = new ObjectMapper().enable(SerializationFeature.INDENT_OUTPUT);
    String response = splitResponse[3].trim().substring(1, splitResponse[3].trim().length() -1);
    ErrorMessage errorMessage = mapper.readValue(response, ErrorMessage.class);
    System.out.println(errorMessage.toString());

    return new ResponseEntity<>(errorMessage, new HttpHeaders(), HttpStatus.INTERNAL_SERVER_ERROR);
}

我终于得到了预期的回应：

{
    "errorId": "z3o1bE8SJrm8WGrxlpIIWe6TNf0NzR",
    "status": "ERROR",
    "operations": "facturx",
    "profile": "client123456",
    "errorMessage": "PDF is missing",
    "createdAt": "2022-03-16T09:18:57.344+00:00"
}