Failure to process URL where path is nothing but "//"

[rstoyanchev]

After upgrading to Dysprosium snapshots, there is one test failure in the Spring Framework in a scenario where the path is nothing but a double slash, e.g. "http://localhost:8080//".

It results in the following:

java.lang.IllegalArgumentException: Expected authority at index 2: //
	at java.net.URI.create(URI.java:852) ~[?:1.8.0_222]
	at reactor.netty.http.HttpOperations.resolvePath(HttpOperations.java:300) ~[reactor-netty-0.9.3.BUILD-SNAPSHOT.jar:0.9.3.BUILD-SNAPSHOT]
	at reactor.netty.http.server.HttpServerOperations.<init>(HttpServerOperations.java:128) ~[reactor-netty-0.9.3.BUILD-SNAPSHOT.jar:0.9.3.BUILD-SNAPSHOT]
	at reactor.netty.http.server.HttpTrafficHandler.channelRead(HttpTrafficHandler.java:157) ~[reactor-netty-0.9.3.BUILD-SNAPSHOT.jar:0.9.3.BUILD-SNAPSHOT]
	at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:377) [netty-transport-4.1.44.Final.jar:4.1.44.Final]
...

This looks like it might be a side effect of refactoring for #926 in dc3fb4b.

[qcastel]

I am currently hitting this issue in Spring Cloud gateway.
It can be reproduced with the following curl:

curl -k --proxy http://localhost:8500 https://example.com/test

(I am testing hoverfly in front of spring cloud gateway btw, https://hoverfly.io/, may help you reproduce the issue)

I thought I would try to see if it is fixed in 0.9.5 but unfortunately, there is still an NPE.

Seems like you re-introduce the bug two days ago, via 327e9b3 @violetagg

Here is the current stack trace:

java.lang.NullPointerException: null
	at reactor.netty.http.HttpOperations.resolvePath(HttpOperations.java:341)
	at reactor.netty.http.server.HttpServerOperations.<init>(HttpServerOperations.java:130)
	at reactor.netty.http.server.HttpTrafficHandler.channelRead(HttpTrafficHandler.java:155)

[violetagg]

@qcastel can you provide more info?

I did the following:

Spring Gateway

@SpringBootApplication
public class DemoApplication {

	public static void main(String[] args) {
		SpringApplication.run(DemoApplication.class, args);
	}

	@Bean
	public RouteLocator myRoutes(RouteLocatorBuilder builder) {
		return builder.routes()
				.route(p -> p
						.path("/get")
						.uri("http://httpbin.org:80"))
				.build();
	}
}

Hoverfly started in capture mode

hoverctl start
hoverctl mode capture

Then Spring Gateway requested like below and the response is received

curl --proxy http://localhost:8500 http://localhost:8080/get
{
  "args": {}, 
  "headers": {
    "Accept": "*/*", 
    "Accept-Encoding": "gzip", 
    "Content-Length": "0", 
.....
}

Running with latest Reactor Netty 0.9.5.BUILD-SNAPSHOT

[qcastel]

Ok so indeed, that wasn't that obvious to reproduce the issue.

Did manage to reproduce it in isolation at the end, I shared a demo repo here: https://github.com/qcastel/reproduce-netty-npe

Essentially two factors are triggering this issue:
1 - you need to proxy to spring cloud gateway
2 - you need to proxy something under https

Thanks for looking at this issue btw!

[violetagg]

@qcastel I can reproduce it

[violetagg]

@qcastel I committed a fix - dfb71cf. It would be great if you can test 0.9.5.BUILD-SNAPSHOT.

[qcastel]

@violetagg Just tried on https://github.com/qcastel/reproduce-netty-npe and think the NPE is resolved now!

Although I do have another error:

curl: (56) Received HTTP code 404 from proxy after CONNECT

I also simplified the reproduction steps to not have hoverfly and directly hit Spring cloud gateway.

I guess I will raise a new ticket on Spring cloud gateway this time!

[violetagg]

@qcastel so the new failure is not in Reactor Netty?

[qcastel]

Hard to tell, I don't get any logs this time. It could still be the netty rejecting the 'CONNECT' requests.
I raised it under spring-cloud/spring-cloud-gateway#1576
I reproduced the issue there (I simplified the reproduction steps btw) https://github.com/qcastel/reproduce-spring-cloud-gateway-error