SpringCloudGateway笔记(5)-netty空指针问题

实际使用遇到的问题 – 响应为空的时候抛异常 java.lang.NullPointerException

在使用SpringBoot 2.0.0.RELEASE + SpringCloud Finchley.RELEASE 版本开发的时候

遇到响应体为空的时候会抛出一个异常

java.lang.NullPointerException: null
	at java.util.concurrent.ConcurrentHashMap.putVal(ConcurrentHashMap.java:1011) ~[na:1.8.0_191]
	at java.util.concurrent.ConcurrentHashMap.put(ConcurrentHashMap.java:1006) ~[na:1.8.0_191]
	at org.springframework.cloud.gateway.filter.NettyRoutingFilter.lambda$filter$3(NettyRoutingFilter.java:117) ~[spring-cloud-gateway-core-2.0.0.RELEASE.jar:2.0.0.RELEASE]
	at reactor.core.publisher.FluxPeek$PeekSubscriber.onNext(FluxPeek.java:177) ~[reactor-core-3.1.7.RELEASE.jar:3.1.7.RELEASE]
	at reactor.core.publisher.FluxMap$MapSubscriber.onNext(FluxMap.java:108) ~[reactor-core-3.1.7.RELEASE.jar:3.1.7.RELEASE]
	at reactor.core.publisher.FluxRetryPredicate$RetryPredicateSubscriber.onNext(FluxRetryPredicate.java:81) ~[reactor-core-3.1.7.RELEASE.jar:3.1.7.RELEASE]
	at reactor.core.publisher.MonoCreate$DefaultMonoSink.success(MonoCreate.java:140) ~[reactor-core-3.1.7.RELEASE.jar:3.1.7.RELEASE]
	at reactor.ipc.netty.channel.PooledClientContextHandler.fireContextActive(PooledClientContextHandler.java:84) ~[reactor-netty-0.7.7.RELEASE.jar:0.7.7.RELEASE]
	at reactor.ipc.netty.http.client.HttpClientOperations.onInboundNext(HttpClientOperations.java:574) ~[reactor-netty-0.7.7.RELEASE.jar:0.7.7.RELEASE]
	at reactor.ipc.netty.channel.ChannelOperationsHandler.channelRead(ChannelOperationsHandler.java:136) ~[reactor-netty-0.7.7.RELEASE.jar:0.7.7.RELEASE]
	at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:362) ~[netty-transport-4.1.24.Final.jar:4.1.24.Final]
	at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:348) ~[netty-transport-4.1.24.Final.jar:4.1.24.Final]
	at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:340) ~[netty-transport-4.1.24.Final.jar:4.1.24.Final]
	at io.netty.channel.CombinedChannelDuplexHandler$DelegatingChannelHandlerContext.fireChannelRead(CombinedChannelDuplexHandler.java:438) ~[netty-transport-4.1.24.Final.jar:4.1.24.Final]
	at io.netty.handler.codec.ByteToMessageDecoder.fireChannelRead(ByteToMessageDecoder.java:310) ~[netty-codec-4.1.24.Final.jar:4.1.24.Final]
	at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:284) ~[netty-codec-4.1.24.Final.jar:4.1.24.Final]
	at io.netty.channel.CombinedChannelDuplexHandler.channelRead(CombinedChannelDuplexHandler.java:253) ~[netty-transport-4.1.24.Final.jar:4.1.24.Final]
	at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:362) ~[netty-transport-4.1.24.Final.jar:4.1.24.Final]
	at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:348) ~[netty-transport-4.1.24.Final.jar:4.1.24.Final]
	at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:340) ~[netty-transport-4.1.24.Final.jar:4.1.24.Final]
	at io.netty.channel.DefaultChannelPipeline$HeadContext.channelRead(DefaultChannelPipeline.java:1434) ~[netty-transport-4.1.24.Final.jar:4.1.24.Final]
	at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:362) ~[netty-transport-4.1.24.Final.jar:4.1.24.Final]
	at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:348) ~[netty-transport-4.1.24.Final.jar:4.1.24.Final]
	at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:965) ~[netty-transport-4.1.24.Final.jar:4.1.24.Final]
	at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:163) ~[netty-transport-4.1.24.Final.jar:4.1.24.Final]
	at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:645) ~[netty-transport-4.1.24.Final.jar:4.1.24.Final]
	at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:580) ~[netty-transport-4.1.24.Final.jar:4.1.24.Final]
	at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:497) ~[netty-transport-4.1.24.Final.jar:4.1.24.Final]
	at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:459) ~[netty-transport-4.1.24.Final.jar:4.1.24.Final]
	at io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:884) ~[netty-common-4.1.24.Final.jar:4.1.24.Final]
	at java.lang.Thread.run(Thread.java:748) ~[na:1.8.0_191]

这个bug在spring-cloud-gateway的github官方issu上有说明

https://github.com/spring-cloud/spring-cloud-gateway/issues/374

是由于响应的header缺少了Content-Type引起的

升级spring-cloud-gateway-core包到2.0.2以上的版本即可解决

GITHUB代码地址

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