Question

我有以下要求：查询外部服务器，以便将结果通知给rest控制器，同时将其保存到mongo。问题是，在以下实现中，当发生mongo错误时，结果不会返回到rest控制器。有什么办法可以将两个调用与rxJAva分离？

public Observable<LowestFareByProvider> lowestFareByProvider(final 
 FlightSearchRequest flightSearchRequest) {
                final FlightSpecification flightSpecification = FlightSpecification.builder()
                        .from(flightSearchRequest.getFrom())
                        .to(flightSearchRequest.getTo())
                        .departure(flightSearchRequest.getDeparture())
                        .build();

                return flightService.lowestFareByProvider(flightSpecification, flightSearchRequest.getProviders())
                        .map(it -> {
                            logger.debug("Saving to db in thread: {}", Thread.currentThread().getName());
                            return lowestFareByProviderRepository.save(it);
                        })
                        .flatMap(Single::toObservable);
            }

Answer 1

当Mongo保存呼叫失败并将结果转发给订户时，您似乎想吃掉错误。

public Observable<LowestFareByProvider> lowestFareByProvider(final 
 FlightSearchRequest flightSearchRequest) {
                final FlightSpecification flightSpecification = FlightSpecification.builder()
                        .from(flightSearchRequest.getFrom())
                        .to(flightSearchRequest.getTo())
                        .departure(flightSearchRequest.getDeparture())
                        .build();

                return flightService.lowestFareByProvider(flightSpecification, flightSearchRequest.getProviders())
                        .flatMap(result -> {
                            logger.debug("Saving to db in thread: {}", Thread.currentThread().getName());
                            return Observable.fromCallable(() -> { lowestFareByProviderRepository.save(result)})
                                             .onErrorReturn(result);
                        });

请检查语法。在这里，onErrorReturn忽略来自Mongo保存调用（如果有）的错误，并将结果转发回订阅者。在您现阶段拥有Single::toObservable的情况下，我删除了Observable。

分离服务调用和数据库存储

1 个答案: