java.lang.NullPointerException: Parameter specified as non-null is null: method a.b.c.ServerMetricsRecorder.recordDataReceived, parameter remoteAddress

[jakshay21]

Summary

For URIs which URI parser is unable to parse, it throws exception which results in remote address being null. When HttpMetricsRecorder interface methods are invoked in Kotlin environment, it results in NPE.

Code Flow

While resolving the path in HttpServerOperations object creation, if URI parser throws any exception due to parsing issue, remote address is coming as null due to connectionInfo being null.

Expected Behavior

Metrics recorder should be invoked successfully. Interface methods params should be marked as nullable so that the implementation could provide specific handling. This would be specific to Kotlin as the arguments are inferred as non-nullable.

Actual Behavior

Resulting in NPE as the interface methods params are non-nullable.

Steps to Reproduce

• Create an implementation of ChannelMetricsRecorder.

• Use any URI which URI parser couldn't resolve. eg - http://localhost:8080/s=set&_method=__construct&method=*&filter[]=system

• When metrics recorder will invoke any of the interface methods requiring remote address, it will result in NPE in Kotlin.

Possible Solution

Mark methods as nullable so that Kotlin can infer the parameters as nullable and implementation could handle those gracefully.

Your Environment

Koltin Version: 1.6.10
reactor-netty-http: 1.0.18

• JVM version : JAVA 17
• OS and version : macOs Ventura 13.2

Stack trace

URI Parser

java.net.URISyntaxException: Illegal character in path at index 63: http://localhost:8080/s=set&_method=__construct&method=*&filter[]=system at java.net.URI$Parser.fail(URI.java:2974) ~[?:?] at java.net.URI$Parser.checkChars(URI.java:3145) ~[?:?] at java.net.URI$Parser.parseHierarchical(URI.java:3227) ~[?:?] at java.net.URI$Parser.parse(URI.java:3175) ~[?:?] at java.net.URI.<init>(URI.java:623) ~[?:?] at java.net.URI.create(URI.java:904) ~[?:?] at reactor.netty.http.HttpOperations.resolvePath(HttpOperations.java:389) ~[reactor-netty-http-1.0.18.jar!/:1.0.18] at reactor.netty.http.server.HttpServerOperations.<init>(HttpServerOperations.java:173) ~[reactor-netty-http-1.0.18.jar!/:1.0.18] at reactor.netty.http.server.HttpServerOperations.<init>(HttpServerOperations.java:148) ~[reactor-netty-http-1.0.18.jar!/:1.0.18] at reactor.netty.http.server.HttpTrafficHandler.channelRead(HttpTrafficHandler.java:213) ~[reactor-netty-http-1.0.18.jar!/:1.0.18] at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379) ~[netty-transport-4.1.76.Final.jar!/:4.1.76.Final] at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365) ~[netty-transport-4.1.76.Final.jar!/:4.1.76.Final] at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357) ~[netty-transport-4.1.76.Final.jar!/:4.1.76.Final] at io.netty.channel.CombinedChannelDuplexHandler$DelegatingChannelHandlerContext.fireChannelRead(CombinedChannelDuplexHandler.java:436) ~[netty-transport-4.1.76.Final.jar!/:4.1.76.Final]

Metrics recorder

io.netty.channel.AbstractChannelHandlerContext -- An exception 'java.lang.NullPointerException: Parameter specified as non-null is null: method com.apple.carrierservices.preauth.config.netty.HubbleHttpServerMetricsRecorder.incrementErrorsCount, parameter remoteAddress' [enable DEBUG level for full stacktrace] was thrown by a user handler's exceptionCaught() method while handling the following exception: java.lang.NullPointerException: Parameter specified as non-null is null: method com.apple.carrierservices.preauth.config.netty.HubbleHttpServerMetricsRecorder.recordDataReceived, parameter remoteAddress at com.apple.carrierservices.preauth.config.netty.HubbleHttpServerMetricsRecorder.recordDataReceived(HubbleHttpServerMetricsRecorder.kt) ~[classes!/:?] at reactor.netty.http.server.AbstractHttpServerMetricsHandler.recordRead(AbstractHttpServerMetricsHandler.java:183) ~[reactor-netty-http-1.0.18.jar!/:1.0.18] at reactor.netty.http.server.AbstractHttpServerMetricsHandler.channelRead(AbstractHttpServerMetricsHandler.java:151) ~[reactor-netty-http-1.0.18.jar!/:1.0.18] at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379) ~[netty-transport-4.1.76.Final.jar!/:4.1.76.Final] at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365) ~[netty-transport-4.1.76.Final.jar!/:4.1.76.Final] at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357) ~[netty-transport-4.1.76.Final.jar!/:4.1.76.Final] at reactor.netty.http.server.HttpTrafficHandler.channelRead(HttpTrafficHandler.java:266) ~[reactor-netty-http-1.0.18.jar!/:1.0.18] at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379) ~[netty-transport-4.1.76.Final.jar!/:4.1.76.Final] at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365) ~[netty-transport-4.1.76.Final.jar!/:4.1.76.Final] at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357) ~[netty-transport-4.1.76.Final.jar!/:4.1.76.Final] at io.netty.channel.CombinedChannelDuplexHandler$DelegatingChannelHandlerContext.fireChannelRead(CombinedChannelDuplexHandler.java:436) ~[netty-transport-4.1.76.Final.jar!/:4.1.76.Final]

[pderop]

Hi @jakshay21 ,

Thanks for reporting this.
I have spent some time on your issue, and will soon provide a PR, but we think that a null remoteAddress parameter should not be passed to metrics recorder interface methods. So the fix will avoid passing null remoteAddress parameters when a bad request URI is received.

thanks.

[jakshay21]

Sounds good. Thanks for the update @pderop