[SLING-5602] The Discovery module does not work any more after a ResourceResolverFactory reactivation

• Type: Bug
• Status: Closed
• Priority: Blocker
• Resolution: Fixed
• Affects Version/s: Resource Resolver 1.4.8
• Fix Version/s: Resource Resolver 1.4.10
• Component/s: ResourceResolver
• Assignee: Carsten Ziegeler
• Reporter: Radu Cotescu
• Created: 14/Mar/16 15:36
• Updated: 26/Sep/19 12:40
• Resolved: 17/Mar/16 17:43

Description

The Discovery module does not work any more after the Resource Resolver Factory is reconfigured. To reproduce this start the latest launchpad (built from https://github.com/apache/sling/blob/c441d5b672d1952a82a1c9fe1e6d81e86cec0018/launchpad/builder/src/main/provisioning/sling.txt) and then:

1. go to http://localhost:8080/system/console/configMgr/org.apache.sling.jcr.resource.internal.JcrResourceResolverFactoryImpl
2. click on save (this will trigger the component's reactivation)
3. check the error log

14.03.2016 16:29:57.331 *ERROR* [discovery.connectors.common.runner.7fd8d00a-802a-4367-a384-64024e28dbbc.discoveryLiteCheck] org.apache.sling.discovery.oak.cluster.OakClusterViewService getLocalClusterView: repository exception: java.lang.Exception: Could not adapt resourceResolver to session: org.apache.sling.resourceresolver.impl.ResourceResolverImpl@499d9cc9
java.lang.Exception: Could not adapt resourceResolver to session: org.apache.sling.resourceresolver.impl.ResourceResolverImpl@499d9cc9
	at org.apache.sling.discovery.commons.providers.spi.base.DiscoveryLiteDescriptor.getDescriptorFrom(DiscoveryLiteDescriptor.java:41)
	at org.apache.sling.discovery.oak.cluster.OakClusterViewService.getLocalClusterView(OakClusterViewService.java:111)
	at org.apache.sling.discovery.base.commons.BaseDiscoveryService.getTopology(BaseDiscoveryService.java:77)
	at org.apache.sling.discovery.oak.OakDiscoveryService.checkForTopologyChange(OakDiscoveryService.java:657)
	at org.apache.sling.discovery.oak.pinger.OakViewChecker.discoveryLiteCheck(OakViewChecker.java:232)
	at org.apache.sling.discovery.oak.pinger.OakViewChecker.access$000(OakViewChecker.java:64)
	at org.apache.sling.discovery.oak.pinger.OakViewChecker$1.run(OakViewChecker.java:208)
	at org.apache.sling.discovery.base.commons.PeriodicBackgroundJob.safelyRun(PeriodicBackgroundJob.java:86)
	at org.apache.sling.discovery.base.commons.PeriodicBackgroundJob.run(PeriodicBackgroundJob.java:77)
	at java.lang.Thread.run(Thread.java:745)
14.03.2016 16:29:57.332 *INFO* [discovery.connectors.common.runner.7fd8d00a-802a-4367-a384-64024e28dbbc.discoveryLiteCheck] org.apache.sling.discovery.base.commons.BaseDiscoveryService getTopology: undefined cluster view: REPOSITORY_EXCEPTION] org.apache.sling.discovery.base.commons.UndefinedClusterViewException: Exception while processing descriptor: java.lang.Exception: Could not adapt resourceResolver to session: org.apache.sling.resourceresolver.impl.ResourceResolverImpl@499d9cc9
14.03.2016 16:29:57.332 *INFO* [discovery.connectors.common.runner.7fd8d00a-802a-4367-a384-64024e28dbbc.discoveryLiteCheck] org.apache.sling.discovery.commons.providers.base.ViewStateManagerImpl enqueueForAll: sending topologyEvent TopologyEvent [type=TOPOLOGY_CHANGING, oldView=DefaultTopologyView[current=false, num=1, instances=7fd8d00a-802a-4367-a384-64024e28dbbc[local=true,leader=true]], newView=null], to all (5) listeners
14.03.2016 16:29:57.332 *ERROR* [Discovery-AsyncEventSender] org.apache.sling.discovery.oak.TopologyWebConsolePlugin addDiscoveryLiteHistoryEntry: Exception: java.lang.Exception: Could not adapt resourceResolver to session: org.apache.sling.resourceresolver.impl.ResourceResolverImpl@149e86f0
java.lang.Exception: Could not adapt resourceResolver to session: org.apache.sling.resourceresolver.impl.ResourceResolverImpl@149e86f0
	at org.apache.sling.discovery.commons.providers.spi.base.DiscoveryLiteDescriptor.getDescriptorFrom(DiscoveryLiteDescriptor.java:41)
	at org.apache.sling.discovery.oak.TopologyWebConsolePlugin.updateDiscoveryLiteHistory(TopologyWebConsolePlugin.java:771)
	at org.apache.sling.discovery.oak.TopologyWebConsolePlugin.handleTopologyEvent(TopologyWebConsolePlugin.java:722)
	at org.apache.sling.discovery.commons.providers.base.AsyncTopologyEvent.trigger(AsyncTopologyEvent.java:53)
	at org.apache.sling.discovery.commons.providers.base.AsyncEventSender.run(AsyncEventSender.java:118)
	at java.lang.Thread.run(Thread.java:745)

The Discovery module will not recover from this state. Furthermore it will also prevent the RRF to reactivate and basically makes the instance unusable.

Issue Links

• is related to: SLING-5561 Resource Resolver Factory should be deactivated before provider is removed
• is related to: SLING-5580 Resource Resolver Factory is wrongly activated when zero or more than one required providers