Span object is null when passing RequestEntity<?> as a request parameter

[techdeba901]

I am using Webflux and Netty in my spring boot app. RequestEntity is the request parameter in my controller class. I am getting 500 'internal server error' for RequestEntity as a parameter. But this service is giving response status 200 for other inputs.

Controller class

@RestController
public class ReactiveController {

	@Autowired
	Tracer tracer;

	@GetMapping("/test")
	@ResponseBody
	public CompletableFuture<ResponseEntity<?>> test(RequestEntity<String> reqEntity,
			@RequestHeader Map<String, String> reqHeaders) {
		final CompletableFuture<ResponseEntity<?>> finalRspCompFuture = new CompletableFuture<>();
		Span span = tracer.activeSpan();
		span.setOperationName("www.google.com");
		ResponseEntity<?> rspEntity = new ResponseEntity<>(HttpStatus.OK);
		finalRspCompFuture.complete(rspEntity);
		return finalRspCompFuture;
	}
}	

Expected behavior

Http Status: 200(Ok)

Actual behavior

Http Status: 500(Internal server error)

Console log:

�[2m2021-07-22 09:36:27.083�[0;39m �[31mERROR�[0;39m �[35m25684�[0;39m �[2m---�[0;39m �[2m[ctor-http-nio-4]�[0;39m �[36ma.w.r.e.AbstractErrorWebExceptionHandler�[0;39m �[2m:�[0;39m [de269c37-1]  500 Server Error for HTTP GET "/test"

java.lang.NullPointerException: Cannot invoke "io.opentracing.Span.setOperationName(String)" because "span" is null
	at com.example.reactiverestservice.controller.ReactiveController.test(ReactiveController.java:26) ~[main/:na]
	Suppressed: reactor.core.publisher.FluxOnAssembly$OnAssemblyException: 
Error has been observed at the following site(s):
	|_ checkpoint ? org.springframework.boot.actuate.metrics.web.reactive.server.MetricsWebFilter [DefaultWebFilterChain]
	|_ checkpoint ? io.opentracing.contrib.spring.web.webfilter.TracingWebFilter [DefaultWebFilterChain]
	|_ checkpoint ? HTTP GET "/test" [ExceptionHandlingWebHandler]
Stack trace:
		at com.example.reactiverestservice.controller.ReactiveController.test(ReactiveController.java:26) ~[main/:na]
		at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
		at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:78) ~[na:na]
		at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
		at java.base/java.lang.reflect.Method.invoke(Method.java:567) ~[na:na]
		at org.springframework.web.reactive.result.method.InvocableHandlerMethod.lambda$invoke$0(InvocableHandlerMethod.java:146) ~[spring-webflux-5.3.4.jar:5.3.4]
		at reactor.core.publisher.MonoFlatMap$FlatMapMain.onNext(MonoFlatMap.java:125) ~[reactor-core-3.4.3.jar:3.4.3]
		at reactor.core.publisher.Operators$MonoSubscriber.complete(Operators.java:1815) ~[reactor-core-3.4.3.jar:3.4.3]
		at reactor.core.publisher.MonoZip$ZipCoordinator.signal(MonoZip.java:251) ~[reactor-core-3.4.3.jar:3.4.3]
		at reactor.core.publisher.MonoZip$ZipInner.onNext(MonoZip.java:336) ~[reactor-core-3.4.3.jar:3.4.3]
		at reactor.core.publisher.MonoPeekTerminal$MonoTerminalPeekSubscriber.onNext(MonoPeekTerminal.java:180) ~[reactor-core-3.4.3.jar:3.4.3]
		at reactor.core.publisher.FluxDefaultIfEmpty$DefaultIfEmptySubscriber.onNext(FluxDefaultIfEmpty.java:100) ~[reactor-core-3.4.3.jar:3.4.3]
		at reactor.core.publisher.Operators$MonoSubscriber.complete(Operators.java:1815) ~[reactor-core-3.4.3.jar:3.4.3]
		at reactor.core.publisher.FluxDefaultIfEmpty$DefaultIfEmptySubscriber.onComplete(FluxDefaultIfEmpty.java:108) ~[reactor-core-3.4.3.jar:3.4.3]
		at reactor.core.publisher.FluxMap$MapSubscriber.onComplete(FluxMap.java:142) ~[reactor-core-3.4.3.jar:3.4.3]
		at reactor.core.publisher.Operators$MultiSubscriptionSubscriber.onComplete(Operators.java:2057) ~[reactor-core-3.4.3.jar:3.4.3]
		at reactor.core.publisher.FluxMapFuseable$MapFuseableSubscriber.onComplete(FluxMapFuseable.java:150) ~[reactor-core-3.4.3.jar:3.4.3]
		at reactor.core.publisher.FluxContextWrite$ContextWriteSubscriber.onComplete(FluxContextWrite.java:126) ~[reactor-core-3.4.3.jar:3.4.3]
		at reactor.core.publisher.FluxMapFuseable$MapFuseableConditionalSubscriber.onComplete(FluxMapFuseable.java:344) ~[reactor-core-3.4.3.jar:3.4.3]
		at reactor.core.publisher.FluxFilterFuseable$FilterFuseableConditionalSubscriber.onComplete(FluxFilterFuseable.java:391) ~[reactor-core-3.4.3.jar:3.4.3]
		at reactor.core.publisher.Operators$MonoSubscriber.complete(Operators.java:1816) ~[reactor-core-3.4.3.jar:3.4.3]
		at reactor.core.publisher.MonoCollect$CollectSubscriber.onComplete(MonoCollect.java:159) ~[reactor-core-3.4.3.jar:3.4.3]
		at reactor.core.publisher.FluxMap$MapSubscriber.onComplete(FluxMap.java:142) ~[reactor-core-3.4.3.jar:3.4.3]
		at reactor.core.publisher.FluxPeek$PeekSubscriber.onComplete(FluxPeek.java:259) ~[reactor-core-3.4.3.jar:3.4.3]
		at reactor.core.publisher.FluxMap$MapSubscriber.onComplete(FluxMap.java:142) ~[reactor-core-3.4.3.jar:3.4.3]
		at reactor.netty.channel.FluxReceive.onInboundComplete(FluxReceive.java:389) ~[reactor-netty-core-1.0.4.jar:1.0.4]
		at reactor.netty.channel.ChannelOperations.onInboundComplete(ChannelOperations.java:396) ~[reactor-netty-core-1.0.4.jar:1.0.4]
		at reactor.netty.http.server.HttpServerOperations.onInboundNext(HttpServerOperations.java:555) ~[reactor-netty-http-1.0.4.jar:1.0.4]
		at reactor.netty.channel.ChannelOperationsHandler.channelRead(ChannelOperationsHandler.java:94) ~[reactor-netty-core-1.0.4.jar:1.0.4]
		at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379) ~[netty-transport-4.1.59.Final.jar:4.1.59.Final]
		at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365) ~[netty-transport-4.1.59.Final.jar:4.1.59.Final]
		at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357) ~[netty-transport-4.1.59.Final.jar:4.1.59.Final]
		at reactor.netty.http.server.HttpTrafficHandler.channelRead(HttpTrafficHandler.java:253) ~[reactor-netty-http-1.0.4.jar:1.0.4]
		at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379) ~[netty-transport-4.1.59.Final.jar:4.1.59.Final]
		at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365) ~[netty-transport-4.1.59.Final.jar:4.1.59.Final]
		at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357) ~[netty-transport-4.1.59.Final.jar:4.1.59.Final]
		at io.netty.channel.CombinedChannelDuplexHandler$DelegatingChannelHandlerContext.fireChannelRead(CombinedChannelDuplexHandler.java:436) ~[netty-transport-4.1.59.Final.jar:4.1.59.Final]
		at io.netty.handler.codec.ByteToMessageDecoder.fireChannelRead(ByteToMessageDecoder.java:324) ~[netty-codec-4.1.59.Final.jar:4.1.59.Final]
		at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:296) ~[netty-codec-4.1.59.Final.jar:4.1.59.Final]
		at io.netty.channel.CombinedChannelDuplexHandler.channelRead(CombinedChannelDuplexHandler.java:251) ~[netty-transport-4.1.59.Final.jar:4.1.59.Final]
		at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379) ~[netty-transport-4.1.59.Final.jar:4.1.59.Final]
		at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365) ~[netty-transport-4.1.59.Final.jar:4.1.59.Final]
		at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357) ~[netty-transport-4.1.59.Final.jar:4.1.59.Final]
		at io.netty.channel.DefaultChannelPipeline$HeadContext.channelRead(DefaultChannelPipeline.java:1410) ~[netty-transport-4.1.59.Final.jar:4.1.59.Final]
		at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379) ~[netty-transport-4.1.59.Final.jar:4.1.59.Final]
		at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365) ~[netty-transport-4.1.59.Final.jar:4.1.59.Final]
		at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:919) ~[netty-transport-4.1.59.Final.jar:4.1.59.Final]
		at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:166) ~[netty-transport-4.1.59.Final.jar:4.1.59.Final]
		at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:719) ~[netty-transport-4.1.59.Final.jar:4.1.59.Final]
		at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:655) ~[netty-transport-4.1.59.Final.jar:4.1.59.Final]
		at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:581) ~[netty-transport-4.1.59.Final.jar:4.1.59.Final]
		at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:493) ~[netty-transport-4.1.59.Final.jar:4.1.59.Final]
		at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:989) ~[netty-common-4.1.59.Final.jar:4.1.59.Final]
		at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74) ~[netty-common-4.1.59.Final.jar:4.1.59.Final]
		at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30) ~[netty-common-4.1.59.Final.jar:4.1.59.Final]
		at java.base/java.lang.Thread.run(Thread.java:831) ~[na:na]

Environment

SpringBootVersion: 2.4.3
java : 16

Source Code

reactive-rest-service.zip