Hibernate Reactive Session/EntityManager is closed

Describe the bug

The following bug appeared at some point between 2.4.0.Final and 2.5.1.Final.

When used in a highly concurrent context, Hibernate Reactive can sometimes throw this exception:

2021-12-21 10:47:57,168 ERROR [org.hib.rea.errors] (vert.x-eventloop-thread-30) HR000057: Failed to execute statement [$1select fruit0_.id as id1_0_, fruit0_.name as name2_0_ from known_fruits fruit0_ order by fruit0_.name]: $2could not execute query: java.util.concurrent.CompletionException: java.lang.IllegalStateException: Session/EntityManager is closed
        at java.base/java.util.concurrent.CompletableFuture.encodeThrowable(CompletableFuture.java:314)
        at java.base/java.util.concurrent.CompletableFuture.completeThrowable(CompletableFuture.java:319)
        at java.base/java.util.concurrent.CompletableFuture$UniCompose.tryFire(CompletableFuture.java:1081)
        at java.base/java.util.concurrent.CompletableFuture.postComplete(CompletableFuture.java:506)
        at java.base/java.util.concurrent.CompletableFuture.complete(CompletableFuture.java:2073)
        at io.vertx.core.Future.lambda$toCompletionStage$2(Future.java:360)
        at io.vertx.core.impl.future.FutureImpl$3.onSuccess(FutureImpl.java:141)
        at io.vertx.core.impl.future.FutureBase.emitSuccess(FutureBase.java:60)
        at io.vertx.core.impl.future.FutureImpl.tryComplete(FutureImpl.java:211)
        at io.vertx.core.impl.future.PromiseImpl.tryComplete(PromiseImpl.java:23)
        at io.vertx.sqlclient.impl.QueryResultBuilder.tryComplete(QueryResultBuilder.java:102)
        at io.vertx.sqlclient.impl.QueryResultBuilder.tryComplete(QueryResultBuilder.java:35)
        at io.vertx.core.Promise.complete(Promise.java:66)
        at io.vertx.core.Promise.handle(Promise.java:51)
        at io.vertx.core.Promise.handle(Promise.java:29)
        at io.vertx.core.impl.future.FutureImpl$3.onSuccess(FutureImpl.java:141)
        at io.vertx.core.impl.future.FutureBase.lambda$emitSuccess$0(FutureBase.java:54)
        at io.netty.util.concurrent.AbstractEventExecutor.safeExecute(AbstractEventExecutor.java:164)
        at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasks(SingleThreadEventExecutor.java:469)
        at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:503)
        at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:986)
        at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74)
        at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
        at java.base/java.lang.Thread.run(Thread.java:829)
Caused by: java.lang.IllegalStateException: Session/EntityManager is closed
        at org.hibernate.internal.AbstractSharedSessionContract.checkOpen(AbstractSharedSessionContract.java:393)
        at org.hibernate.engine.spi.SharedSessionContractImplementor.checkOpen(SharedSessionContractImplementor.java:148)
        at org.hibernate.reactive.session.impl.ReactiveSessionImpl.checkOpen(ReactiveSessionImpl.java:1558)
        at org.hibernate.internal.AbstractSharedSessionContract.checkOpenOrWaitingForAutoClose(AbstractSharedSessionContract.java:399)
        at org.hibernate.internal.SessionImpl.getEntityUsingInterceptor(SessionImpl.java:617)
        at org.hibernate.loader.Loader.getRow(Loader.java:1610)
        at org.hibernate.loader.Loader.getRowFromResultSet(Loader.java:748)
        at org.hibernate.loader.Loader.getRowsFromResultSet(Loader.java:1047)
        at org.hibernate.reactive.loader.hql.impl.ReactiveQueryLoader.getRowsFromResultSet(ReactiveQueryLoader.java:223)
        at org.hibernate.reactive.loader.ReactiveLoaderBasedResultSetProcessor.reactiveExtractResults(ReactiveLoaderBasedResultSetProcessor.java:73)
        at org.hibernate.reactive.loader.hql.impl.ReactiveQueryLoader$1.reactiveExtractResults(ReactiveQueryLoader.java:72)
        at org.hibernate.reactive.loader.ReactiveLoader.reactiveProcessResultSet(ReactiveLoader.java:145)
        at org.hibernate.reactive.loader.ReactiveLoader.lambda$doReactiveQueryAndInitializeNonLazyCollections$0(ReactiveLoader.java:77)
        at java.base/java.util.concurrent.CompletableFuture$UniCompose.tryFire(CompletableFuture.java:1072)
        ... 21 more

2021-12-21 10:47:57,168 ERROR [org.acm.hib.rea.FruitMutinyResource] (vert.x-eventloop-thread-30) Failed to handle request: java.lang.IllegalStateException: Session/EntityManager is closed
        at org.hibernate.internal.AbstractSharedSessionContract.checkOpen(AbstractSharedSessionContract.java:393)
        at org.hibernate.engine.spi.SharedSessionContractImplementor.checkOpen(SharedSessionContractImplementor.java:148)
        at org.hibernate.reactive.session.impl.ReactiveSessionImpl.checkOpen(ReactiveSessionImpl.java:1558)
        at org.hibernate.internal.AbstractSharedSessionContract.checkOpenOrWaitingForAutoClose(AbstractSharedSessionContract.java:399)
        at org.hibernate.internal.SessionImpl.getEntityUsingInterceptor(SessionImpl.java:617)
        at org.hibernate.loader.Loader.getRow(Loader.java:1610)
        at org.hibernate.loader.Loader.getRowFromResultSet(Loader.java:748)
        at org.hibernate.loader.Loader.getRowsFromResultSet(Loader.java:1047)
        at org.hibernate.reactive.loader.hql.impl.ReactiveQueryLoader.getRowsFromResultSet(ReactiveQueryLoader.java:223)
        at org.hibernate.reactive.loader.ReactiveLoaderBasedResultSetProcessor.reactiveExtractResults(ReactiveLoaderBasedResultSetProcessor.java:73)
        at org.hibernate.reactive.loader.hql.impl.ReactiveQueryLoader$1.reactiveExtractResults(ReactiveQueryLoader.java:72)
        at org.hibernate.reactive.loader.ReactiveLoader.reactiveProcessResultSet(ReactiveLoader.java:145)
        at org.hibernate.reactive.loader.ReactiveLoader.lambda$doReactiveQueryAndInitializeNonLazyCollections$0(ReactiveLoader.java:77)
        at java.base/java.util.concurrent.CompletableFuture$UniCompose.tryFire(CompletableFuture.java:1072)
        at java.base/java.util.concurrent.CompletableFuture.postComplete(CompletableFuture.java:506)
        at java.base/java.util.concurrent.CompletableFuture.complete(CompletableFuture.java:2073)
        at io.vertx.core.Future.lambda$toCompletionStage$2(Future.java:360)
        at io.vertx.core.impl.future.FutureImpl$3.onSuccess(FutureImpl.java:141)
        at io.vertx.core.impl.future.FutureBase.emitSuccess(FutureBase.java:60)
        at io.vertx.core.impl.future.FutureImpl.tryComplete(FutureImpl.java:211)
        at io.vertx.core.impl.future.PromiseImpl.tryComplete(PromiseImpl.java:23)
        at io.vertx.sqlclient.impl.QueryResultBuilder.tryComplete(QueryResultBuilder.java:102)
        at io.vertx.sqlclient.impl.QueryResultBuilder.tryComplete(QueryResultBuilder.java:35)
        at io.vertx.core.Promise.complete(Promise.java:66)
        at io.vertx.core.Promise.handle(Promise.java:51)
        at io.vertx.core.Promise.handle(Promise.java:29)
        at io.vertx.core.impl.future.FutureImpl$3.onSuccess(FutureImpl.java:141)
        at io.vertx.core.impl.future.FutureBase.lambda$emitSuccess$0(FutureBase.java:54)
        at io.netty.util.concurrent.AbstractEventExecutor.safeExecute(AbstractEventExecutor.java:164)
        at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasks(SingleThreadEventExecutor.java:469)
        at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:503)
        at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:986)
        at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74)
        at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
        at java.base/java.lang.Thread.run(Thread.java:829)

Expected behavior

No response

Actual behavior

No response

How to Reproduce?

Reproducer: https://github.com/quarkusio/quarkus-quickstarts/tree/main/hibernate-reactive-quickstart

Steps to reproduce the behavior:

1. Change the Quarkus version to something between 2.4.0.Final and 2.5.4.Final
2. Run jmeter test plan.zip with JMeter
3. The exception should show up in log eventually

Output of uname -a or ver

Linux glepage.remote.csb 4.18.0-348.2.1.el8_5.x86_64 #1 SMP Mon Nov 8 13:30:15 EST 2021 x86_64 x86_64 x86_64 GNU/Linux

Output of java -version

openjdk version “11.0.13” 2021-10-19 LTS

GraalVM version (if different from Java)

No response

Quarkus version or git rev

2.5.4.Final

Build tool (ie. output of mvnw --version or gradlew --version)

No response

Additional information

No response

[DavideD]

But how come this is the case? If a session is still being used by the second query then why is the first query able to close it?

The session gets closed at the end of the withSession: https://github.com/hibernate/hibernate-reactive/blob/main/hibernate-reactive-core/src/main/java/org/hibernate/reactive/mutiny/impl/MutinySessionFactoryImpl.java#L250

The session is not thread-safe. There are no check in place to make sure that it doesn’t get closed if somebody else is still using it. In this case, thread-safe doesn’t only mean that it must not be shared between threads. It means that when you have two parallel async pipelines, they cannot share the session.

Also, withSession doesn’t always creates a new session. It checks first if one exists in the current Vert.x context and, if it’s the case, it will reuse it.

openSession doesn’t check anything, it just creates a new session every time. That’s why in this case it solves the issue.

Can you explain/point me to documentation on how the eventually(session::close) works? How does it know when to close the session?

It’s part of the Mutiny API: https://github.com/smallrye/smallrye-mutiny/blob/main/implementation/src/main/java/io/smallrye/mutiny/Uni.java#L549

It’s similar to a finally block:

• if the previous uni completes successfully, it will chain the call to session.close and then return the result of the previous uni (basically, it behaves the same as .call{ () -> session.close()})
• if the previous uni fails, it will run session.close and when it completes, propagate the failure

[DavideD]

Thanks @LajosPolya, I can see the error now. I will try to figure out what’s going on and let you know