Changes to Resource no longer support custom url schemes.

[janbartel]

jetty-12

In previous versions of jetty, a call like Resource.newResource("bundleresource://62.fwk1116834242/org/eclipse/jetty/webapp/webdefault.xml") would return a URLResource that could be used to eg open an input stream and read the xml content.

In jetty-12, we get the following exception instead:

Found defaults descriptor via WebXmlConfiguration.classloader: bundleresource://62.fwk1116834242/org/eclipse/jetty/ee9/webapp/webdefault-ee9.xml
2022-11-11 13:53:43.834:WARN :oejew.WebAppContext:Start Level: Equinox Container: ac1d208f-4617-41a3-b6a8-a7a1b3d9eea7: Failed startup of context o.e.j.e.w.WebAppContext@7a8e2a3c{ROOT,/,jar:file:///home/janb/src/jetty-eclipse/jetty-12.0.x/jetty-ee9/jetty-ee9-osgi/test-jetty-ee9-osgi/target/1668135220776-0/org.eclipse.osgi/89/0/bundleFile!/,false}{jar:file:/home/janb/src/jetty-eclipse/jetty-12.0.x/jetty-ee9/jetty-ee9-osgi/test-jetty-ee9-osgi/target/1668135220776-0/org.eclipse.osgi/89/0/bundleFile!/}
java.nio.file.FileSystemNotFoundException: Provider "bundleresource" not installed
at java.base/java.nio.file.Path.of(Path.java:212)
at java.base/java.nio.file.Paths.get(Paths.java:98)
at org.eclipse.jetty.util.resource.MountedPathResource.of(MountedPathResource.java:33)
at org.eclipse.jetty.util.resource.Resource.create(Resource.java:91)
at org.eclipse.jetty.util.resource.ResourceFactoryInternals$LifeCycle.newResource(ResourceFactoryInternals.java:113)
at org.eclipse.jetty.ee9.webapp.WebXmlConfiguration.preConfigure(WebXmlConfiguration.java:67)
at org.eclipse.jetty.ee9.webapp.Configurations.preConfigure(Configurations.java:498)
at org.eclipse.jetty.ee9.webapp.WebAppContext.preConfigure(WebAppContext.java:499)
at org.eclipse.jetty.ee9.webapp.WebAppContext.doStart(WebAppContext.java:528)
at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:93)
at org.eclipse.jetty.util.component.ContainerLifeCycle.start(ContainerLifeCycle.java:171)
at org.eclipse.jetty.util.component.ContainerLifeCycle.doStart(ContainerLifeCycle.java:114)
at org.eclipse.jetty.server.Handler$Abstract.doStart(Handler.java:391)
at org.eclipse.jetty.server.handler.ContextHandler.lambda$doStart$0(ContextHandler.java:535)
at org.eclipse.jetty.server.handler.ContextHandler$Context.call(ContextHandler.java:1053)
at org.eclipse.jetty.server.handler.ContextHandler.doStart(ContextHandler.java:535)
at org.eclipse.jetty.ee9.nested.ContextHandler$CoreContextHandler.doStart(ContextHandler.java:2391)
at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:93)
at org.eclipse.jetty.deploy.bindings.StandardStarter.processBinding(StandardStarter.java:40)
at org.eclipse.jetty.deploy.AppLifeCycle.runBindings(AppLifeCycle.java:183)
at org.eclipse.jetty.deploy.DeploymentManager.requestAppGoal(DeploymentManager.java:519)
at org.eclipse.jetty.deploy.DeploymentManager.addApp(DeploymentManager.java:165)
at org.eclipse.jetty.osgi.BundleWebAppProvider.bundleAdded(BundleWebAppProvider.java:202)
at org.eclipse.jetty.osgi.BundleWebAppProvider$WebAppTracker.addingBundle(BundleWebAppProvider.java:72)
at org.osgi.util.tracker.BundleTracker$Tracked.customizerAdding(BundleTracker.java:477)
at org.osgi.util.tracker.BundleTracker$Tracked.customizerAdding(BundleTracker.java:422)
at org.osgi.util.tracker.AbstractTracked.trackAdding(AbstractTracked.java:258)
at org.osgi.util.tracker.AbstractTracked.track(AbstractTracked.java:231)
at org.osgi.util.tracker.BundleTracker$Tracked.bundleChanged(BundleTracker.java:452)
at org.eclipse.osgi.internal.framework.BundleContextImpl.dispatchEvent(BundleContextImpl.java:949)
at org.eclipse.osgi.framework.eventmgr.EventManager.dispatchEvent(EventManager.java:234)
at org.eclipse.osgi.framework.eventmgr.ListenerQueue.dispatchEventSynchronous(ListenerQueue.java:151)
at org.eclipse.osgi.internal.framework.EquinoxEventPublisher.publishBundleEventPrivileged(EquinoxEventPublisher.java:229)
at org.eclipse.osgi.internal.framework.EquinoxEventPublisher.publishBundleEvent(EquinoxEventPublisher.java:138)
at org.eclipse.osgi.internal.framework.EquinoxEventPublisher.publishBundleEvent(EquinoxEventPublisher.java:130)
at org.eclipse.osgi.internal.framework.EquinoxContainerAdaptor.publishModuleEvent(EquinoxContainerAdaptor.java:217)
at org.eclipse.osgi.container.Module.publishEvent(Module.java:499)
at org.eclipse.osgi.container.Module.start(Module.java:486)
at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel$2.run(ModuleContainer.java:1852)
at org.eclipse.osgi.internal.framework.EquinoxContainerAdaptor$1$1.execute(EquinoxContainerAdaptor.java:136)
at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel.incStartLevel(ModuleContainer.java:1845)
at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel.incStartLevel(ModuleContainer.java:1788)
at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel.doContainerStartLevel(ModuleContainer.java:1750)
at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel.dispatchEvent(ModuleContainer.java:1672)
at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel.dispatchEvent(ModuleContainer.java:1)
at org.eclipse.osgi.framework.eventmgr.EventManager.dispatchEvent(EventManager.java:234)
at org.eclipse.osgi.framework.eventmgr.EventManager$EventThread.run(EventManager.java:345)

[gregw]

@lorban @joakime can one of you take this issue. Moderately important as it is blocking Jan's work.

I think the issue is here: https://github.com/eclipse/jetty.project/blob/jetty-12.0.x/jetty-core/jetty-util/src/main/java/org/eclipse/jetty/util/resource/Resource.java#L87-L91

We assume a URI is either able to be handled by PathResource or it can be mounted. This is not true for URIs that have some arbitrary scheme and a UrlStreamHandler installed for them.

So I think we need to revive UrlResource and come up with some logic to determine which scheme to use it for. There is a private method: java.net.URL#providers that discovers all the providers, so I guess we can do the same thing to get a list. But do we use that as a black list or a white list? as there will be handlers for things like "file", which we want Path to handle, and things like "jar" that we want to mount.

Perhaps we just have a curated list of protocols that we will mount and everything else is tried a UrlResource as last gasp effort?

[joakime]

We should be super wary of supporting custom URL streams in the long run.
The JDK is undergoing some serious changes for how this works ATM.

[joakime]

Opened PR #8888 to experiment with having Resource be created from a registered list of URI schemes that can results in a ResourceFactory that knows how to support that URI scheme.
See ResourceFactoryTest there for example

[lorban]

This also looks related: https://bugs.eclipse.org/bugs/show_bug.cgi?id=570590

[joakime]

Closing, addressed in PR #8888