Intermittent ConcurrentModificationException during JBoss EAP startup with Keycloak adapter

[mhajas]

Before reporting an issue

• I have searched existing issues
• I have reproduced the issue with the latest release

Area

adapter/jee

Describe the bug

Already reported in Jira: https://issues.redhat.com/browse/KEYCLOAK-7254

When the Keycloak subsystem is used to configure client deployment the following exception is intermittently thrown:

(MSC service thread 1-4) MSC000001: Failed to start service org.wildfly.security.http-server-mechanism-factory."some-client.war": org.jboss.msc.service.StartException in service org.wildfly.security.http-server-mechanism-factory."some-client.war": Failed to start service
at org.jboss.msc.service.ServiceControllerImpl$StartTask.execute(ServiceControllerImpl.java:1731)
at org.jboss.msc.service.ServiceControllerImpl$ControllerTask.run(ServiceControllerImpl.java:1559)
at org.jboss.threads.ContextClassLoaderSavingRunnable.run(ContextClassLoaderSavingRunnable.java:35)
at org.jboss.threads.EnhancedQueueExecutor.safeRun(EnhancedQueueExecutor.java:1990)
at org.jboss.threads.EnhancedQueueExecutor$ThreadBody.doRunTask(EnhancedQueueExecutor.java:1486)
at org.jboss.threads.EnhancedQueueExecutor$ThreadBody.run(EnhancedQueueExecutor.java:1363)
at java.lang.Thread.run(Thread.java:750)
Caused by: java.util.ConcurrentModificationException
at java.util.LinkedHashMap$LinkedHashIterator.nextNode(LinkedHashMap.java:719)
at java.util.LinkedHashMap$LinkedEntryIterator.next(LinkedHashMap.java:752)
at java.util.LinkedHashMap$LinkedEntryIterator.next(LinkedHashMap.java:750)
at org.jboss.dmr.ObjectModelValue.asPropertyList(ObjectModelValue.java:161)
at org.jboss.dmr.ModelNode.asPropertyList(ModelNode.java:529)
at org.keycloak.subsystem.adapter.extension.KeycloakAdapterConfigService.setJSONValues(KeycloakAdapterConfigService.java:267)
at org.keycloak.subsystem.adapter.extension.KeycloakAdapterConfigService.getJSON(KeycloakAdapterConfigService.java:261)
at org.keycloak.subsystem.adapter.extension.KeycloakHttpAuthenticationFactoryService.start(KeycloakHttpAuthenticationFactoryService.java:50)
at org.jboss.msc.service.ServiceControllerImpl$StartTask.startService(ServiceControllerImpl.java:1739)
at org.jboss.msc.service.ServiceControllerImpl$StartTask.execute(ServiceControllerImpl.java:1701)
... 6 more

Version

18.0.2

Expected behavior

No CME is thrown

Actual behavior

CME is intermittently thrown

How to Reproduce?

Anything else?

• There was a PR already created for this but it was not finished [KEYCLOAK-7254] - Intermittent CME during server start #5202
• war files associated with the error message do not need to be deployed to the server group.

[mposolda]

Considering that we are going to remove OIDC adapters (which are already deprecated), this looks like very low priority.

[keycloak-github-bot]

Due to the amount of issues reported by the community we are not able to prioritise resolving this issue at the moment.

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