Custom component: org.xwiki.component.manager.ComponentLookupException

mvdschot · August 19, 2020, 10:01am

Hi,

We are running a couple of custom components without trouble.
But this new component is giving problems. It is installed on farm level and contains new REST endpoints.

Installation by the Extentionmanager runs fine.

After calling my new endpoint I get the following error:

org.xwiki.component.manager.ComponentLookupException: Failed to lookup component [wiki.XXX.farm.restapi.WebApiResource] identified by type [interface org.xwiki.rest.XWikiRestComponent] and hint [wiki.XXX.farm.restapi.WebApiResource]

In components.txt I’ve added all component java files.

Does someone has a hint?

Thanks for helping out,
Maarten

vmassol · August 19, 2020, 10:06am

Hi, to help you out you need to provide:

The component’s java code (at least the class declaration with the annotations)
The content of your components.txt

Also, did you restart XWiki? I think REST components might require a restart to be registered as REST endpoints but I’m not sure.

Thx

mvdschot · August 19, 2020, 10:12am

Hi,

The class declaration:

@Component
@Named("wiki.cf.farm.restapi.WebApiResource")
@Path("/api/v1")

public class WebApiResource extends XWikiResource
{

The components.txt (the relevant bit)

wiki.cf.farm.restapi.WebApiResource
wiki.cf.farm.restapi.core.db.internal.DefaultDBFunctions
wiki.cf.farm.restapi.core.provider.internal.DefaultBaseObjectProvider
wiki.cf.farm.restapi.core.provider.internal.DefaultCoreKlasseProvider
wiki.cf.farm.restapi.core.provider.internal.DefaultDocumentReferenceProvider
wiki.cf.farm.restapi.core.provider.internal.DefaultXWikiDocumentProvider

Thanks!

Edit: yes, I restarted the wiki

vmassol · August 19, 2020, 10:49am

That looks good so all I could recommend is to check for typos, make sure that components.txt is in META-INF/.

You could also try building your extension with the latest xwiki contrib parent since it has some checks to verify component registration by default (See the spoon checks on https://dev.xwiki.org/xwiki/bin/view/Community/Building/#HAutomaticChecks).

mvdschot · August 19, 2020, 10:50am

Just before the above error I get:

Aug 19, 2020 10:47:07 AM org.restlet.ext.jaxrs.internal.util.ExceptionHandler instantiateExecption

WARNING: Could not create new instance of root resource class

vmassol · August 19, 2020, 10:51am

I guess that message is because of the error you mention (i.e the ComponentManager cannot get the component).

vmassol · August 19, 2020, 10:53am

So FTR this is not needed anymore thanks to Loading...

mvdschot · August 19, 2020, 10:55am

Yes I did the restart

vmassol · August 19, 2020, 10:57am

My point was that you don’t need to do a restart…

mflorea · August 20, 2020, 6:55am

Can you give us the full stack trace. The root cause is usually at the end. The problem may be with one of the components injected in WebApiResource.

mvdschot · August 20, 2020, 9:01am

Hi,

This is the full stack trace:

Aug 20, 2020 8:49:35 AM org.restlet.ext.jaxrs.internal.util.ExceptionHandler instantiateExecption
WARNING: Could not create new instance of root resource class
org.xwiki.component.manager.ComponentLookupException: Failed to lookup component [wiki.cf.farm.restapi.WebApiResource] identified by type [interface org.xwiki.rest.XWikiRestComponent] and hint [wiki.cf.farm.restapi.WebApiResource]
	at org.xwiki.component.embed.EmbeddableComponentManager.getInstance(EmbeddableComponentManager.java:204)
	at org.xwiki.component.embed.EmbeddableComponentManager.getInstance(EmbeddableComponentManager.java:210)
	at org.xwiki.component.internal.multi.DelegateComponentManager.getInstance(DelegateComponentManager.java:83)
	at org.xwiki.component.internal.multi.DelegateComponentManager.getInstance(DelegateComponentManager.java:83)
	at org.xwiki.component.internal.multi.DelegateComponentManager.getInstance(DelegateComponentManager.java:83)
	at org.xwiki.component.internal.multi.DelegateComponentManager.getInstance(DelegateComponentManager.java:83)
	at org.xwiki.component.internal.multi.DelegateComponentManager.getInstance(DelegateComponentManager.java:83)
	at org.xwiki.rest.internal.ComponentsObjectFactory.getInstance(ComponentsObjectFactory.java:67)
	at org.restlet.ext.jaxrs.internal.wrappers.PerRequestRootResourceClass.getInstance(PerRequestRootResourceClass.java:97)
	at org.restlet.ext.jaxrs.JaxRsRestlet.instantiateRrc(JaxRsRestlet.java:963)
	at org.restlet.ext.jaxrs.JaxRsRestlet.identifyRootResource(JaxRsRestlet.java:942)
	at org.restlet.ext.jaxrs.JaxRsRestlet.requestMatching(JaxRsRestlet.java:1161)
	at org.restlet.ext.jaxrs.JaxRsRestlet.handle(JaxRsRestlet.java:742)
	at org.restlet.routing.Filter.doHandle(Filter.java:150)
	at org.restlet.routing.Filter.handle(Filter.java:197)
	at org.restlet.routing.Router.doHandle(Router.java:422)
	at org.restlet.routing.Router.handle(Router.java:641)
	at org.restlet.routing.Filter.doHandle(Filter.java:150)
	at org.restlet.routing.Filter.handle(Filter.java:197)
	at org.restlet.routing.Filter.doHandle(Filter.java:150)
	at org.restlet.routing.Filter.handle(Filter.java:197)
	at org.restlet.routing.Filter.doHandle(Filter.java:150)
	at org.restlet.routing.Filter.handle(Filter.java:197)
	at org.restlet.routing.Filter.doHandle(Filter.java:150)
	at org.restlet.routing.Filter.handle(Filter.java:197)
	at org.restlet.routing.Filter.doHandle(Filter.java:150)
	at org.restlet.engine.application.StatusFilter.doHandle(StatusFilter.java:140)
	at org.restlet.routing.Filter.handle(Filter.java:197)
	at org.restlet.routing.Filter.doHandle(Filter.java:150)
	at org.restlet.routing.Filter.handle(Filter.java:197)
	at org.restlet.engine.CompositeHelper.handle(CompositeHelper.java:202)
	at org.restlet.engine.application.ApplicationHelper.handle(ApplicationHelper.java:77)
	at org.restlet.Application.handle(Application.java:385)
	at org.restlet.routing.Filter.doHandle(Filter.java:150)
	at org.restlet.routing.Filter.handle(Filter.java:197)
	at org.restlet.routing.Router.doHandle(Router.java:422)
	at org.restlet.routing.Router.handle(Router.java:641)
	at org.restlet.routing.Filter.doHandle(Filter.java:150)
	at org.restlet.routing.Filter.handle(Filter.java:197)
	at org.restlet.routing.Router.doHandle(Router.java:422)
	at org.restlet.routing.Router.handle(Router.java:641)
	at org.restlet.routing.Filter.doHandle(Filter.java:150)
	at org.restlet.routing.Filter.handle(Filter.java:197)
	at org.restlet.engine.CompositeHelper.handle(CompositeHelper.java:202)
	at org.restlet.Component.handle(Component.java:408)
	at org.restlet.Server.handle(Server.java:507)
	at org.restlet.engine.connector.ServerHelper.handle(ServerHelper.java:63)
	at org.restlet.engine.adapter.HttpServerHelper.handle(HttpServerHelper.java:143)
	at org.restlet.ext.servlet.ServerServlet.service(ServerServlet.java:1117)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	at org.xwiki.wysiwyg.filter.XWikiContextInitializationFilter.doFilter(XWikiContextInitializationFilter.java:85)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	at org.xwiki.container.servlet.filters.internal.SetHTTPHeaderFilter.doFilter(SetHTTPHeaderFilter.java:63)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	at org.xwiki.container.servlet.filters.internal.SavedRequestRestorerFilter.doFilter(SavedRequestRestorerFilter.java:208)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	at org.xwiki.container.servlet.filters.internal.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:111)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	at org.xwiki.resource.servlet.RoutingFilter.doFilter(RoutingFilter.java:132)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:543)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81)
	at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:690)
	at org.apache.catalina.valves.RemoteIpValve.invoke(RemoteIpValve.java:747)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
	at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:615)
	at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
	at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:818)
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1627)
	at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	at java.base/java.lang.Thread.run(Thread.java:834)
Caused by: org.xwiki.component.manager.ComponentLookupException: Failed to lookup component [wiki.cf.farm.restapi.core.provider.internal.DefaultXWikiDocumentProvider] identified by type [interface wiki.cf.farm.restapi.core.provider.XWikiDocumentProvider] and hint [default]
	at org.xwiki.component.embed.EmbeddableComponentManager.getInstance(EmbeddableComponentManager.java:204)
	at org.xwiki.component.embed.EmbeddableComponentManager.getDependencyInstance(EmbeddableComponentManager.java:406)
	at org.xwiki.component.embed.EmbeddableComponentManager.createInstance(EmbeddableComponentManager.java:355)
	at org.xwiki.component.embed.EmbeddableComponentManager.getComponentInstance(EmbeddableComponentManager.java:457)
	at org.xwiki.component.embed.EmbeddableComponentManager.getInstance(EmbeddableComponentManager.java:201)
	... 84 more
Caused by: org.xwiki.component.manager.ComponentLookupException: Failed to lookup component [wiki.cf.farm.restapi.core.db.internal.DefaultDBFunctions] identified by type [interface wiki.cf.farm.restapi.core.db.DBFunctions] and hint [default]
	at org.xwiki.component.embed.EmbeddableComponentManager.getInstance(EmbeddableComponentManager.java:204)
	at org.xwiki.component.embed.EmbeddableComponentManager.getDependencyInstance(EmbeddableComponentManager.java:406)
	at org.xwiki.component.embed.EmbeddableComponentManager.createInstance(EmbeddableComponentManager.java:355)
	at org.xwiki.component.embed.EmbeddableComponentManager.getComponentInstance(EmbeddableComponentManager.java:451)
	at org.xwiki.component.embed.EmbeddableComponentManager.getInstance(EmbeddableComponentManager.java:201)
	... 88 more
Caused by: org.xwiki.component.manager.ComponentLookupException: Can't find descriptor for the component with type [class java.lang.String] and hint [default]
	at org.xwiki.component.embed.EmbeddableComponentManager.getInstance(EmbeddableComponentManager.java:212)
	at org.xwiki.component.embed.EmbeddableComponentManager.getDependencyInstance(EmbeddableComponentManager.java:406)
	at org.xwiki.component.embed.EmbeddableComponentManager.createInstance(EmbeddableComponentManager.java:355)
	at org.xwiki.component.embed.EmbeddableComponentManager.getComponentInstance(EmbeddableComponentManager.java:451)
	at org.xwiki.component.embed.EmbeddableComponentManager.getInstance(EmbeddableComponentManager.java:201)
	... 92 more

vmassol · August 20, 2020, 9:06am

Here you go…

Good catch Marius.

mvdschot · August 20, 2020, 9:11am

Thanks!

Coming from c# and php… Why is this happening?

vmassol · August 20, 2020, 9:13am

It’s your code so you should know!

Check or paste the content of wiki.cf.farm.restapi.core.db.internal.DefaultDBFunctions. You probaby have some wrong @Inject there.

mvdschot · August 20, 2020, 9:14am

Haha, you’re right I will check and post the outcome.

mvdschot · August 20, 2020, 9:22am

Here comes the moment (which every developer has) of shaming. But always educational about how to read the error.

The @Inject was not commented out, but was ment to. So the it was looking for a component named “String”.

@Inject
//private Reporter reporter;

private static String SelectFrom

Thank you for pointing this out

vmassol · August 20, 2020, 9:28am

Glad you found it!