Provided SubscriptionExecutionStrategy is not used

[vinterdo]

Hello,

I tried to create a subscription, where I send info every time an Entity (from Hibernate) is updated. I encountered similar problem as with queries - LazyInitializationException. In the case of Queries, it was easily resolved by creating custom execution strategy, where execute is annotated as Transactional:

@Service
open class TransactionalQueryExecutionStrategy : AsyncExecutionStrategy() {

    @Transactional
    override fun execute(executionContext: ExecutionContext, parameters: ExecutionStrategyParameters): CompletableFuture<ExecutionResult> {
        return super.execute(executionContext, parameters)
    }
}

For subscription, I created something similar, except executeSubscriptionEvent method is annotated as Transactional.
And is injected by creating DefaultExecutionStrategyProvider:

    @Bean
    open fun executionStrategies(
            queryExecutionStrategy: TransactionalQueryExecutionStrategy,
            mutationExecutionStrategy: TransactionalMutationExecutionStrategy,
            subscriptionExecutionStrategy: TransactionalSubscriptionExecutionStrategy
    ) : ExecutionStrategyProvider {
        return DefaultExecutionStrategyProvider(queryExecutionStrategy, mutationExecutionStrategy, subscriptionExecutionStrategy)
    }

It works for queries and mutations like a charm. But for subscriptions, the problem is still there:

java.util.concurrent.CompletionException: org.hibernate.LazyInitializationException: failed to lazily initialize a collection of role: pl.vinterdo.sto.gamesession.entities.GameSession.invitedPlayers, could not initialize proxy - no Session
	at java.base/java.util.concurrent.CompletableFuture.encodeThrowable(CompletableFuture.java:331) ~[na:na]
	at java.base/java.util.concurrent.CompletableFuture.uniApplyNow(CompletableFuture.java:670) ~[na:na]
	at java.base/java.util.concurrent.CompletableFuture.uniApplyStage(CompletableFuture.java:658) ~[na:na]
	at java.base/java.util.concurrent.CompletableFuture.thenApply(CompletableFuture.java:2094) ~[na:na]
	at graphql.execution.SubscriptionExecutionStrategy.executeSubscriptionEvent(SubscriptionExecutionStrategy.java:104) ~[graphql-java-14.0.jar:na]
	at graphql.execution.SubscriptionExecutionStrategy.lambda$null$0(SubscriptionExecutionStrategy.java:47) ~[graphql-java-14.0.jar:na]
	at graphql.execution.reactive.CompletionStageMappingPublisher$1.onNext(CompletionStageMappingPublisher.java:47) ~[graphql-java-14.0.jar:na]
	at io.reactivex.rxjava3.internal.util.HalfSerializer.onNext(HalfSerializer.java:45) ~[rxjava-3.0.4.jar:na]
	at io.reactivex.rxjava3.internal.subscribers.StrictSubscriber.onNext(StrictSubscriber.java:97) ~[rxjava-3.0.4.jar:na]
	at io.reactivex.rxjava3.internal.operators.flowable.FlowableConcatArray$ConcatArraySubscriber.onNext(FlowableConcatArray.java:77) ~[rxjava-3.0.4.jar:na]
	at io.reactivex.rxjava3.internal.subscriptions.ScalarSubscription.request(ScalarSubscription.java:55) ~[rxjava-3.0.4.jar:na]
	at io.reactivex.rxjava3.internal.subscriptions.SubscriptionArbiter.setSubscription(SubscriptionArbiter.java:99) ~[rxjava-3.0.4.jar:na]
	at io.reactivex.rxjava3.internal.operators.flowable.FlowableConcatArray$ConcatArraySubscriber.onSubscribe(FlowableConcatArray.java:71) ~[rxjava-3.0.4.jar:na]
	at io.reactivex.rxjava3.internal.operators.flowable.FlowableJust.subscribeActual(FlowableJust.java:34) ~[rxjava-3.0.4.jar:na]
	at io.reactivex.rxjava3.core.Flowable.subscribe(Flowable.java:15750) ~[rxjava-3.0.4.jar:na]
	at io.reactivex.rxjava3.core.Flowable.subscribe(Flowable.java:15696) ~[rxjava-3.0.4.jar:na]
	at io.reactivex.rxjava3.internal.operators.flowable.FlowableConcatArray$ConcatArraySubscriber.onComplete(FlowableConcatArray.java:140) ~[rxjava-3.0.4.jar:na]
	at io.reactivex.rxjava3.internal.operators.flowable.FlowableConcatArray.subscribeActual(FlowableConcatArray.java:40) ~[rxjava-3.0.4.jar:na]
	at io.reactivex.rxjava3.core.Flowable.subscribe(Flowable.java:15750) ~[rxjava-3.0.4.jar:na]
	at io.reactivex.rxjava3.core.Flowable.subscribe(Flowable.java:15699) ~[rxjava-3.0.4.jar:na]
	at graphql.execution.reactive.CompletionStageMappingPublisher.subscribe(CompletionStageMappingPublisher.java:34) ~[graphql-java-14.0.jar:na]
	at graphql.kickstart.execution.subscriptions.DefaultSubscriptionSession.subscribe(DefaultSubscriptionSession.java:37) ~[graphql-java-servlet-9.1.0.jar:na]
	at graphql.kickstart.execution.subscriptions.apollo.SubscriptionStartCommand.handleSubscriptionStart(SubscriptionStartCommand.java:46) ~[graphql-java-servlet-9.1.0.jar:na]
	at graphql.kickstart.execution.subscriptions.apollo.SubscriptionStartCommand.lambda$apply$1(SubscriptionStartCommand.java:32) ~[graphql-java-servlet-9.1.0.jar:na]
	at java.base/java.util.concurrent.CompletableFuture.uniAcceptNow(CompletableFuture.java:753) ~[na:na]
	at java.base/java.util.concurrent.CompletableFuture.uniAcceptStage(CompletableFuture.java:731) ~[na:na]
	at java.base/java.util.concurrent.CompletableFuture.thenAccept(CompletableFuture.java:2108) ~[na:na]
	at graphql.kickstart.execution.subscriptions.apollo.SubscriptionStartCommand.apply(SubscriptionStartCommand.java:32) ~[graphql-java-servlet-9.1.0.jar:na]
	at graphql.kickstart.execution.subscriptions.apollo.ApolloSubscriptionConsumer.accept(ApolloSubscriptionConsumer.java:24) ~[graphql-java-servlet-9.1.0.jar:na]
	at graphql.kickstart.execution.subscriptions.apollo.ApolloSubscriptionConsumer.accept(ApolloSubscriptionConsumer.java:11) ~[graphql-java-servlet-9.1.0.jar:na]
	at graphql.kickstart.servlet.GraphQLWebsocketServlet$1.onMessage(GraphQLWebsocketServlet.java:127) ~[graphql-java-servlet-9.1.0.jar:na]
	at graphql.kickstart.servlet.GraphQLWebsocketServlet$1.onMessage(GraphQLWebsocketServlet.java:123) ~[graphql-java-servlet-9.1.0.jar:na]
	at org.apache.tomcat.websocket.WsFrameBase.sendMessageText(WsFrameBase.java:395) ~[tomcat-embed-websocket-9.0.33.jar:9.0.33]
	at org.apache.tomcat.websocket.server.WsFrameServer.sendMessageText(WsFrameServer.java:119) ~[tomcat-embed-websocket-9.0.33.jar:9.0.33]
	at org.apache.tomcat.websocket.WsFrameBase.processDataText(WsFrameBase.java:495) ~[tomcat-embed-websocket-9.0.33.jar:9.0.33]
	at org.apache.tomcat.websocket.WsFrameBase.processData(WsFrameBase.java:294) ~[tomcat-embed-websocket-9.0.33.jar:9.0.33]
	at org.apache.tomcat.websocket.WsFrameBase.processInputBuffer(WsFrameBase.java:133) ~[tomcat-embed-websocket-9.0.33.jar:9.0.33]
	at org.apache.tomcat.websocket.server.WsFrameServer.onDataAvailable(WsFrameServer.java:82) ~[tomcat-embed-websocket-9.0.33.jar:9.0.33]
	at org.apache.tomcat.websocket.server.WsFrameServer.doOnDataAvailable(WsFrameServer.java:171) ~[tomcat-embed-websocket-9.0.33.jar:9.0.33]
	at org.apache.tomcat.websocket.server.WsFrameServer.notifyDataAvailable(WsFrameServer.java:151) ~[tomcat-embed-websocket-9.0.33.jar:9.0.33]
	at org.apache.tomcat.websocket.server.WsHttpUpgradeHandler.upgradeDispatch(WsHttpUpgradeHandler.java:148) ~[tomcat-embed-websocket-9.0.33.jar:9.0.33]
	at org.apache.coyote.http11.upgrade.UpgradeProcessorInternal.dispatch(UpgradeProcessorInternal.java:54) ~[tomcat-embed-core-9.0.33.jar:9.0.33]
	at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:59) ~[tomcat-embed-core-9.0.33.jar:9.0.33]
	at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868) ~[tomcat-embed-core-9.0.33.jar:9.0.33]
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1594) ~[tomcat-embed-core-9.0.33.jar:9.0.33]
	at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) ~[tomcat-embed-core-9.0.33.jar:9.0.33]
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128) ~[na:na]
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628) ~[na:na]
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) ~[tomcat-embed-core-9.0.33.jar:9.0.33]
	at java.base/java.lang.Thread.run(Thread.java:834) ~[na:na]

As you can see from stack trace, subscription execution strategy from graphql java is used, not the one I provided.

I also tried using map to inject my strategies, with strategies renamed to expected names:

@Bean
    open fun executionStrategies() : ExecutionStrategyProvider {
        return DefaultExecutionStrategyProvider(QueryExecutionStrategy(), MutationExecutionStrategy(), SubscriptionExecutionStrategy());
        executionStrategyMap[QUERY_EXECUTION_STRATEGY] = QueryExecutionStrategy()
        executionStrategyMap[MUTATION_EXECUTION_STRATEGY] =
        executionStrategyMap[SUBSCRIPTION_EXECUTION_STRATEGY] =
        return executionStrategyMap;
    }

But the effect was the same

[BartoszF]

I came across the same problem.
It would be nice, if someone with better understanding of how it's working underneath, would look at this.

[BartoszF]

Looks similar to #358

[Aqu1nt]

Can be solved by providing a custom GraphQLBuilder bean that overrides the default bean configured in GraphQLWebsocketAutoConfiguration.

    // Needed due to "Provided SubscriptionExecutionStrategy is not used #430"
    // https://github.com/graphql-java-kickstart/graphql-spring-boot/issues/430
    // @see GraphQLWebsocketAutoConfiguration#graphQLInvoker
    @Bean
    fun graphQLBuilder(executionStrategyProvider: ExecutionStrategyProvider): GraphQLBuilder {
        val builder = GraphQLBuilder()
        builder.executionStrategyProvider { executionStrategyProvider }
        return builder
    }

[oliemansm]

The next version will pick the ExecutionStrategyProvider bean up and configure it automatically instead of having to provide your own GraphQLBuilder.