Spring webclient未记录错误响应并在收到错误时执行使用者操作

Question

我有一个Spring引导服务，其中API通过RouterFunction公开。一旦收到API请求，就会触发某些验证。其中一个验证，通过网络客户端调用另一个应用编程接口来验证接收到的值是否存在。如果value不存在，则必须记录错误消息并将错误消息添加到数组列表中。

但是，下面的实现既不记录错误也不记录成功消息，也无法在数组列表中添加错误消息。

我也试图使用块（），但这给了

'IllegalStateException: block()/blockFirst()/blockLast() are blocking, which is not supported in thread reactor-http-epoll-3'

如果我通过RouterFunction直接公开一个API来调用该查找API，那么一切都正常。这表明，通过验证层进行调用导致了问题，可能是同步和反应式调用方式的一些问题。

我无法理解我的实现的问题。请指导我做错了什么。

触发外部验证的验证类

@Slf4j
@Component
@RequiredArgsConstructor
public class EmployeeValidation{
    
    private final IdentityApiClient identityApiClient;
    
    public List<ErrorDetail> validate(Optional<EmployeeRequestDto> employeeRequest) {
        var errors = new ArrayList<ErrorDetail>();
        employeeRequest
                .ifPresent(employee -> {
                    //some other validations
                    if (errors.isEmpty()) {
                        validateIfIdentityExist(employee.getSecuredEmployeeDetail(), errors::add);
                    }
                });
        return errors;
    }
    
    private void validateIfIdentityExist(SecuredEmployeeDetailDto securedEmployeeDetailDto, Consumer<ErrorDetail> errorDetailConsumer) {
        Optional.ofNullable(securedEmployeeDetailDto)
                .map(SecuredEmployeeDetailDto::getIdentity)
                .ifPresent(identityLocal -> {
                    log.info("Going to retrieve identity [{}] detail", identityLocal);
                    identityApiClient.retrieveIdentityDetail(identityLocal)
                            .doOnError(e -> errorDetailConsumer.accept(new ErrorDetail(REQUEST_INVALID_PARAM, e.getMessage())));

                });
    }
}

正在调用另一个API以验证值的Webclient

@Slf4j
@Component
@RequiredArgsConstructor
public class IdentityApiClient {

    private final WebClient identityWebClient;
    private final IdentityProperties identityProperties;
    
    public Mono<IdentityDetail> retrieveIdentityDetail(String identity) {
        log.info("Going to retrieve identity [{}] detail", identity);
        return identityWebClient
                .get()
                .uri(identityProperties.getLookupPath(), Map.of("identity", identity))
                .retrieve()
                .onStatus(httpStatus -> httpStatus.equals(UNAUTHORIZED),
                        clientResponse -> clientResponse.bodyToMono(String.class)
                                .flatMap(identityLookUpErrorResponse -> Mono.error(new IdentityLookUpException(UNAUTHORIZED.value(), IdentityLookUpErrorResponse.builder()
                                        .error(identityLookUpErrorResponse)
                                        .message("Unauthorized Access")
                                        .status(UNAUTHORIZED.value())
                                        .build()))))
                .onStatus(HttpStatus::is4xxClientError,
                        clientResponse -> clientResponse.bodyToMono(IdentityLookUpErrorResponse.class)
                                .switchIfEmpty(Mono.just(IdentityLookUpErrorResponse.builder()
                                        .error("Received Empty Response Body")
                                        .message("Unknown Identity")
                                        .status(NOT_FOUND.value())
                                        .build()))
                                .flatMap(identityLookUpErrorResponse -> Mono.error(new IdentityLookUpException(identityLookUpErrorResponse.getStatus(), identityLookUpErrorResponse))))
                .onStatus(HttpStatus::is5xxServerError,
                        clientResponse -> clientResponse.bodyToMono(IdentityLookUpErrorResponse.class)
                                .switchIfEmpty(Mono.just(IdentityLookUpErrorResponse.builder()
                                        .error("Received Empty Response Body")
                                        .message(INTERNAL_SERVER_ERROR.getReasonPhrase())
                                        .status(INTERNAL_SERVER_ERROR.value())
                                        .build()))
                                .flatMap(identityLookUpErrorResponse -> Mono.error(new IdentityLookUpException(identityLookUpErrorResponse.getStatus(), identityLookUpErrorResponse))))
                .bodyToMono(IdentityDetail.class)
                .doOnNext(response -> log.info("Identity [{}] response received", response)) // not getting logged when called via validator class
                .doOnError(e -> log.error("Identity [{}] error response received", identity, e));// not getting logged when called via validator class
    }   
}

Answer 1

此方法返回一个未被任何人订阅的Mono。此代码在隔离状态下不执行任何操作。

identityApiClient.retrieveIdentityDetail(identityLocal)
                            .doOnError(e -> errorDetailConsumer.accept(new ErrorDetail(REQUEST_INVALID_PARAM, e.getMessage())));

反应式编程的咒语是

“在您订阅之前不会发生任何事情”

对于大多数用例，基础框架（在本例中为Spring）将为您订阅Mono，只要您从您的RouterFunction返回它。

我不完全熟悉您的需求，但一个可能的解决方案是重构您的验证器，使其具有反应性，并将其添加到您的反应性流中。