2018-09-04 19:27:48.860 ERROR 349 --- [reactor-http-client-epoll-8] c.pearson.ltg.book.services.BookService  : | onError(org.springframework.web.reactive.function.client.WebClientResponseException: ClientResponse has erroneous status code: 400 Bad Request)
2018-09-04 19:27:48.861 ERROR 349 --- [reactor-http-client-epoll-8] c.pearson.ltg.book.services.BookService  : 

org.springframework.web.reactive.function.client.WebClientResponseException: ClientResponse has erroneous status code: 400 Bad Request
	at org.springframework.web.reactive.function.client.DefaultWebClient$DefaultResponseSpec.lambda$createResponseException$7(DefaultWebClient.java:472)
	at reactor.core.publisher.FluxMap$MapSubscriber.onNext(FluxMap.java:100)
	at reactor.core.publisher.FluxDefaultIfEmpty$DefaultIfEmptySubscriber.onNext(FluxDefaultIfEmpty.java:92)
	at reactor.core.publisher.FluxMapFuseable$MapFuseableSubscriber.onNext(FluxMapFuseable.java:115)
	at reactor.core.publisher.FluxMapFuseable$MapFuseableSubscriber.onNext(FluxMapFuseable.java:115)
	at reactor.core.publisher.FluxFilterFuseable$FilterFuseableSubscriber.onNext(FluxFilterFuseable.java:104)
	at reactor.core.publisher.Operators$MonoSubscriber.complete(Operators.java:1073)
	at reactor.core.publisher.MonoCollectList$MonoBufferAllSubscriber.onComplete(MonoCollectList.java:117)
	at reactor.core.publisher.FluxMap$MapSubscriber.onComplete(FluxMap.java:130)
	at reactor.core.publisher.FluxMap$MapSubscriber.onComplete(FluxMap.java:130)
	at reactor.ipc.netty.channel.FluxReceive.terminateReceiver(FluxReceive.java:377)
	at reactor.ipc.netty.channel.FluxReceive.drainReceiver(FluxReceive.java:202)
	at reactor.ipc.netty.channel.FluxReceive.onInboundComplete(FluxReceive.java:342)
	at reactor.ipc.netty.channel.ChannelOperations.onInboundComplete(ChannelOperations.java:336)
	at reactor.ipc.netty.channel.ChannelOperations.onHandlerTerminate(ChannelOperations.java:403)
	at reactor.ipc.netty.http.client.HttpClientOperations.onInboundNext(HttpClientOperations.java:601)
	at reactor.ipc.netty.channel.ChannelOperationsHandler.channelRead(ChannelOperationsHandler.java:136)
	at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:362)
	at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:348)
	at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:340)
	at io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:102)
	at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:362)
	at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:348)
	at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:340)
	at io.netty.channel.CombinedChannelDuplexHandler$DelegatingChannelHandlerContext.fireChannelRead(CombinedChannelDuplexHandler.java:438)
	at io.netty.handler.codec.ByteToMessageDecoder.fireChannelRead(ByteToMessageDecoder.java:310)
	at io.netty.handler.codec.ByteToMessageDecoder.channelInputClosed(ByteToMessageDecoder.java:371)
	at io.netty.handler.codec.ByteToMessageDecoder.channelInactive(ByteToMessageDecoder.java:342)
	at io.netty.handler.codec.http.HttpClientCodec$Decoder.channelInactive(HttpClientCodec.java:282)
	at io.netty.channel.CombinedChannelDuplexHandler.channelInactive(CombinedChannelDuplexHandler.java:223)
	at io.netty.channel.AbstractChannelHandlerContext.invokeChannelInactive(AbstractChannelHandlerContext.java:245)
	at io.netty.channel.AbstractChannelHandlerContext.invokeChannelInactive(AbstractChannelHandlerContext.java:231)
	at io.netty.channel.AbstractChannelHandlerContext.fireChannelInactive(AbstractChannelHandlerContext.java:224)
	at io.netty.handler.codec.ByteToMessageDecoder.channelInputClosed(ByteToMessageDecoder.java:377)
	at io.netty.handler.codec.ByteToMessageDecoder.channelInactive(ByteToMessageDecoder.java:342)
	at io.netty.handler.ssl.SslHandler.channelInactive(SslHandler.java:1028)
	at io.netty.channel.AbstractChannelHandlerContext.invokeChannelInactive(AbstractChannelHandlerContext.java:245)
	at io.netty.channel.AbstractChannelHandlerContext.invokeChannelInactive(AbstractChannelHandlerContext.java:231)
	at io.netty.channel.AbstractChannelHandlerContext.fireChannelInactive(AbstractChannelHandlerContext.java:224)
	at io.netty.channel.DefaultChannelPipeline$HeadContext.channelInactive(DefaultChannelPipeline.java:1429)
	at io.netty.channel.AbstractChannelHandlerContext.invokeChannelInactive(AbstractChannelHandlerContext.java:245)
	at io.netty.channel.AbstractChannelHandlerContext.invokeChannelInactive(AbstractChannelHandlerContext.java:231)
	at io.netty.channel.DefaultChannelPipeline.fireChannelInactive(DefaultChannelPipeline.java:947)
	at io.netty.channel.AbstractChannel$AbstractUnsafe$8.run(AbstractChannel.java:822)
	at io.netty.util.concurrent.AbstractEventExecutor.safeExecute(AbstractEventExecutor.java:163)
	at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasks(SingleThreadEventExecutor.java:404)
	at io.netty.channel.epoll.EpollEventLoop.run(EpollEventLoop.java:309)
	at io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:886)
	at java.lang.Thread.run(Thread.java:748)