App that depends on Tomcat and on Jetty's websocket-server module fails to start with IllegalStateException: WebSocketComponents has not been created

[bukajsytlos]

Spring boot 3.1.5
Seems there is still some issues with websocket autoconfiguration similar to #37660 .
Suggested workaround to disable websocket autoconfig works

2023-11-02T10:16:24.603+01:00 ERROR 3257818 --- [    Test worker] o.a.c.c.C.[Tomcat].[localhost].[/]       : Exception starting filter [org.eclipse.jetty.websocket.servlet.WebSocketUpgradeFilter]

java.lang.IllegalStateException: WebSocketComponents has not been created
	at org.eclipse.jetty.websocket.core.server.WebSocketServerComponents.getWebSocketComponents(WebSocketServerComponents.java:131)
	at org.eclipse.jetty.websocket.core.server.WebSocketMappings.ensureMappings(WebSocketMappings.java:68)
	at org.eclipse.jetty.websocket.servlet.WebSocketUpgradeFilter.init(WebSocketUpgradeFilter.java:182)
	at org.apache.catalina.core.ApplicationFilterConfig.initFilter(ApplicationFilterConfig.java:263)
	at org.apache.catalina.core.ApplicationFilterConfig.<init>(ApplicationFilterConfig.java:102)
	at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:4271)
	at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:4886)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:171)
	at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1332)
	at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1322)
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
	at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75)
	at java.base/java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:145)
	at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:866)
	at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:845)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:171)
	at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1332)
	at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1322)
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
	at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75)
	at java.base/java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:145)
	at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:866)
	at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:240)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:171)
	at org.apache.catalina.core.StandardService.startInternal(StandardService.java:433)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:171)
	at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:917)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:171)
	at org.apache.catalina.startup.Tomcat.start(Tomcat.java:488)
	at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.initialize(TomcatWebServer.java:123)
	at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.<init>(TomcatWebServer.java:104)
	```

[wilkinsona]

Judging by the stack trace, you appear to be trying to use Jetty's WebSocketUpgradeFilter with Tomcat. This isn't supported. It may be that WebSocketServletAutoConfiguration is registering the filter but that would require Jetty's web socket-server module to be on the classpath at the same time as Tomcat. Can you please provide a minimal sample that reproduces the problem?

[bukajsytlos]

This happens just by upgrading from 3.1.3 to 3.1.5 FAForever/faf-java-api#787

[wilkinsona]

There are dependencies on both Tomcat (through spring-boot-starter-web) and Jetty (through spring-boot-starter-jetty). That's rather unusual but, as I suspected, it is the cause of the problem. We can address that in Spring Boot, but you may want to tidy up your dependencies as I doubt that both are needed.

[bukajsytlos]

Thanks "moved" to tomcat.
We had

configurations {
  compile.exclude module: "spring-boot-starter-tomcat"

apparently no longer works (if ever) and with correct exclusion, we run into #33044