415 unsupported media type when using mount to add routes

[mgeorge]

This is a weird one that started happening since 3.0.8 onwards.

If I add a POST route that is declared in another router via a mount then I get a 415 error when POSTing a valid JSON payload.

If I add the same route directly to the server, I get the expected valid response.

Best demonstrated via the following MWE:

import io.jooby.Jooby;
import io.jooby.StatusCode;
import io.jooby.gson.GsonModule;

public class WidgetService extends Jooby {

	public WidgetService() {
		install(new GsonModule());

		post("/api/widgets1", ctx -> {
			Widget widget = ctx.body().to(Widget.class);
			System.out.println("Created " + widget);
			return ctx.send(StatusCode.CREATED);
		});

		mount(new WidgetRouter());

	}

	public static void main(String[] args) {
		new WidgetService().start();
	}

}

class WidgetRouter extends Jooby {

	public WidgetRouter() {

		post("/api/widgets2", ctx -> {
			Widget widget = ctx.body().to(Widget.class);
			System.out.println("Created " + widget);
			return ctx.send(StatusCode.CREATED);
		});

	}
}

Widget is just a POJO with a couple of string fields.

A POST containing valid JSON to /api/widgets1 works and returns the expected 201 response.

The same POST to /api/widgets2 throws a 415 unsupported media type with the following stack trace:

ERROR WidgetService - POST /api/widgets2 415 Unsupported Media Type
 io.jooby.exception.UnsupportedMediaType: application/json
	at io.jooby.MessageDecoder.lambda$static$0(MessageDecoder.java:24)
	at io.jooby.DefaultContext.decode(DefaultContext.java:420)
	at io.jooby.internal.netty.NettyBody.to(NettyBody.java:103)
	at io.jooby.Body.to(Body.java:100)
	at WidgetRouter.lambda$new$baa66101$1(WidgetService.java:32)
	at io.jooby.internal.handler.DefaultHandler.lambda$apply$e67b40fd$1(DefaultHandler.java:21)
	at io.jooby.Route$Filter$1.apply(Route.java:94)
	at io.jooby.internal.handler.WorkerHandler.lambda$apply$0(WorkerHandler.java:22)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1144)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:642)
	at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
	at java.base/java.lang.Thread.run(Thread.java:1583)

I'm using the following dependencies in my build.gradle:

dependencies {
	def joobyVer = '3.2.7';
	implementation group: 'io.jooby', name: 'jooby-netty', version: joobyVer;
	implementation group: 'io.jooby', name: 'jooby-gson', version: joobyVer;
	implementation group: 'ch.qos.logback', name: 'logback-classic', version: '1.5.6';
}

I've been messing around with this for a bit trying to work out why my service started breaking after I upgraded from 3.0.7 to 3.2.7, and as far as I can tell, it is the use of mount to add the route that leads to the 415 error.

I've tried Jackson instead of Gson, and get the same result.

As mentioned, versions prior to 3.0.8 don't seem to have this problem.

[kliushnichenko]

try to use install(WidgetRouter::new) instead of mount

[mgeorge]

Thanks - that did the trick.

Does that mean that mount is now deprecated? The documentation still shows it as the first option for composing routers:

https://jooby.io/#router-composing-mount

[mgeorge]

Also, sometimes you just need to call the constructor on the router in order to pass parameters. The mount method is the obvious way to do this.

[edgar-espina-wpp]

mount should work. There is a silly difference between them: mount fetch install only routes from app, while install copy services, routes, etc...

[kliushnichenko]

if so, that #3400 was the bug as well. And a fix (or at least a part of it) is here 7370e5a, can revive the PR

[jknack]

@kliushnichenko first of all apologies for missing the point when you raised the bug, but yea this is the same bug as #3400. Going to send PR and you can look if I'm still missing something

[kliushnichenko]

no worries, appreciate your support

[mgeorge]

Can confirm that this fixes my problem. Thanks for the good work.