User Provider SPI not working for pagination

[shubhamdev4]

I have deployed the user-provider SPI and it is working.
When I fetch users in keycloak users tab it shows initial 10 results but when I click on next page it throws JSON error.

Keycloak Dashboard Error

No users found, could be due to wrongly configured federated provider Unexpected non-whitespace character after JSON at position 2

Keycloak Server Error

ERROR [org.keycloak.services.error.KeycloakErrorHandler] (executor-thread-5) Uncaught server error: com.fasterxml.jackson.databind.JsonMappingException: [no message for java.lang.NullPointerException]
	at com.fasterxml.jackson.databind.ser.DefaultSerializerProvider._wrapAsIOE(DefaultSerializerProvider.java:509)
	at com.fasterxml.jackson.databind.ser.DefaultSerializerProvider._serialize(DefaultSerializerProvider.java:482)
	at com.fasterxml.jackson.databind.ser.DefaultSerializerProvider.serializeValue(DefaultSerializerProvider.java:400)
	at com.fasterxml.jackson.databind.ObjectWriter$Prefetch.serialize(ObjectWriter.java:1514)
	at com.fasterxml.jackson.databind.ObjectWriter.writeValue(ObjectWriter.java:1007)
	at org.jboss.resteasy.plugins.providers.jackson.ResteasyJackson2Provider.writeTo(ResteasyJackson2Provider.java:345)
	at org.jboss.resteasy.core.interception.jaxrs.ServerWriterInterceptorContext.lambda$writeTo$1(ServerWriterInterceptorContext.java:79)
	at io.quarkus.resteasy.runtime.standalone.VertxHttpRequest$VertxExecutionContext.executeBlockingIo(VertxHttpRequest.java:251)
	at org.jboss.resteasy.core.interception.jaxrs.ServerWriterInterceptorContext.writeTo(ServerWriterInterceptorContext.java:79)
	at org.jboss.resteasy.core.interception.jaxrs.AbstractWriterInterceptorContext.syncProceed(AbstractWriterInterceptorContext.java:245)
	at org.jboss.resteasy.core.interception.jaxrs.AbstractWriterInterceptorContext.proceed(AbstractWriterInterceptorContext.java:224)
	at org.keycloak.quarkus.runtime.integration.jaxrs.TransactionalResponseInterceptor.aroundWriteTo(TransactionalResponseInterceptor.java:41)
	at org.jboss.resteasy.core.interception.jaxrs.AbstractWriterInterceptorContext.syncProceed(AbstractWriterInterceptorContext.java:254)
	at org.jboss.resteasy.core.interception.jaxrs.AbstractWriterInterceptorContext.getStarted(AbstractWriterInterceptorContext.java:170)
	at org.jboss.resteasy.core.interception.jaxrs.ServerWriterInterceptorContext.lambda$getStarted$0(ServerWriterInterceptorContext.java:73)
	at org.jboss.resteasy.core.interception.jaxrs.ServerWriterInterceptorContext.aroundWriteTo(ServerWriterInterceptorContext.java:93)
	at org.jboss.resteasy.core.interception.jaxrs.ServerWriterInterceptorContext.getStarted(ServerWriterInterceptorContext.java:73)
	at org.jboss.resteasy.core.ServerResponseWriter.lambda$writeNomapResponse$3(ServerResponseWriter.java:163)
	at org.jboss.resteasy.core.interception.jaxrs.ContainerResponseContextImpl.filter(ContainerResponseContextImpl.java:410)
	at org.jboss.resteasy.core.ServerResponseWriter.executeFilters(ServerResponseWriter.java:252)
	at org.jboss.resteasy.core.ServerResponseWriter.writeNomapResponse(ServerResponseWriter.java:101)
	at org.jboss.resteasy.core.ServerResponseWriter.writeNomapResponse(ServerResponseWriter.java:74)
	at org.jboss.resteasy.core.SynchronousDispatcher.writeResponse(SynchronousDispatcher.java:594)
	at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:524)
	at org.jboss.resteasy.core.SynchronousDispatcher.lambda$invoke$4(SynchronousDispatcher.java:261)
	at org.jboss.resteasy.core.SynchronousDispatcher.lambda$preprocess$0(SynchronousDispatcher.java:161)
	at org.jboss.resteasy.core.interception.jaxrs.PreMatchContainerRequestContext.filter(PreMatchContainerRequestContext.java:364)
	at org.jboss.resteasy.core.SynchronousDispatcher.preprocess(SynchronousDispatcher.java:164)
	at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:247)
	at io.quarkus.resteasy.runtime.standalone.RequestDispatcher.service(RequestDispatcher.java:73)
	at io.quarkus.resteasy.runtime.standalone.VertxRequestHandler.dispatch(VertxRequestHandler.java:151)
	at io.quarkus.resteasy.runtime.standalone.VertxRequestHandler.handle(VertxRequestHandler.java:82)
	at io.quarkus.resteasy.runtime.standalone.VertxRequestHandler.handle(VertxRequestHandler.java:42)
	at io.vertx.ext.web.impl.RouteState.handleContext(RouteState.java:1284)
	at io.vertx.ext.web.impl.RoutingContextImplBase.iterateNext(RoutingContextImplBase.java:173)
	at io.vertx.ext.web.impl.RoutingContextImpl.next(RoutingContextImpl.java:140)
	at io.quarkus.vertx.http.runtime.StaticResourcesRecorder$2.handle(StaticResourcesRecorder.java:84)
	at io.quarkus.vertx.http.runtime.StaticResourcesRecorder$2.handle(StaticResourcesRecorder.java:71)
	at io.vertx.ext.web.impl.RouteState.handleContext(RouteState.java:1284)
	at io.vertx.ext.web.impl.RoutingContextImplBase.iterateNext(RoutingContextImplBase.java:173)
	at io.vertx.ext.web.impl.RoutingContextImpl.next(RoutingContextImpl.java:140)
	at io.quarkus.vertx.http.runtime.VertxHttpRecorder$6.handle(VertxHttpRecorder.java:430)
	at io.quarkus.vertx.http.runtime.VertxHttpRecorder$6.handle(VertxHttpRecorder.java:408)
	at io.vertx.ext.web.impl.RouteState.handleContext(RouteState.java:1284)
	at io.vertx.ext.web.impl.RoutingContextImplBase.iterateNext(RoutingContextImplBase.java:173)
	at io.vertx.ext.web.impl.RoutingContextImpl.next(RoutingContextImpl.java:140)
	at org.keycloak.quarkus.runtime.integration.web.QuarkusRequestFilter.lambda$createBlockingHandler$0(QuarkusRequestFilter.java:82)
	at io.quarkus.vertx.core.runtime.VertxCoreRecorder$14.runWith(VertxCoreRecorder.java:564)
	at org.jboss.threads.EnhancedQueueExecutor$Task.run(EnhancedQueueExecutor.java:2449)
	at org.jboss.threads.EnhancedQueueExecutor$ThreadBody.run(EnhancedQueueExecutor.java:1478)
	at org.jboss.threads.DelegatingRunnable.run(DelegatingRunnable.java:29)
	at org.jboss.threads.ThreadLocalResettingRunnable.run(ThreadLocalResettingRunnable.java:29)
	at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
	at java.base/java.lang.Thread.run(Thread.java:829)
Caused by: java.lang.NullPointerException
	at dasniko.keycloak.user.PeanutsUserProvider.searchForUserStream(PeanutsUserProvider.java:183)
	at org.keycloak.storage.user.UserQueryProvider.searchForUserStream(UserQueryProvider.java:186)
	at org.keycloak.storage.user.UserQueryProvider.getUsersCount(UserQueryProvider.java:78)
	at org.keycloak.storage.UserStorageManager.lambda$searchForUserStream$25(UserStorageManager.java:453)
	at org.keycloak.storage.UserStorageManager.lambda$query$7(UserStorageManager.java:224)
	at java.base/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:176)
	at java.base/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:177)
	at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:195)
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1541)
	at java.base/java.util.stream.SortedOps$RefSortingSink.end(SortedOps.java:395)
	at java.base/java.util.stream.Sink$ChainedReference.end(Sink.java:258)
	at java.base/java.util.stream.Sink$ChainedReference.end(Sink.java:258)
	at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:485)
	at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:474)
	at java.base/java.util.stream.StreamSpliterators$WrappingSpliterator.forEachRemaining(StreamSpliterators.java:312)
	at java.base/java.util.stream.Streams$ConcatSpliterator.forEachRemaining(Streams.java:735)
	at java.base/java.util.stream.Streams$ConcatSpliterator.forEachRemaining(Streams.java:734)
	at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:484)
	at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:474)
	at java.base/java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:150)
	at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:173)
	at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
	at java.base/java.util.stream.ReferencePipeline.forEachOrdered(ReferencePipeline.java:502)
	at com.fasterxml.jackson.datatype.jdk8.StreamSerializer.serialize(StreamSerializer.java:71)
	at com.fasterxml.jackson.datatype.jdk8.StreamSerializer.serialize(StreamSerializer.java:15)
	at com.fasterxml.jackson.databind.ser.DefaultSerializerProvider._serialize(DefaultSerializerProvider.java:480)
	... 52 more

[dasniko]

It's possible that this repo and these examples are not free of errors. They are - examples!
If you want to use them, feel free, but please don't expect to get support in any way.
Thanks for your understanding.