Apollo Client hangs in Java / Spring Boot app

[SledgeHammer01]

I'm trying to use the Apollo Client Java in my Spring Boot 2.2.2.RELEASE app. Just a simple console app test app that calls my GraphQL server. The application fails to exit if I make an Apollo call. Either through legacy .enqueue / callback or RX2. I have to click the stop button TWICE to exit.

Here are some specifics:

Java: 13
Spring Boot: 2.2.2.RELEASE

dependencies {
	classpath("com.apollographql.apollo:apollo-gradle-plugin-incubating:1.2.2")
}

plugins {
id 'org.springframework.boot' version '2.2.2.RELEASE'
id 'io.spring.dependency-management' version '1.0.8.RELEASE'
id 'java'
}

sourceCompatibility = '13'
targetCompatibility = '13'

apollo {
suppressRawTypesWarning = true
}

dependencies {
implementation 'org.springframework.boot:spring-boot-starter-web:2.2.2.RELEASE'
implementation 'org.springframework.boot:spring-boot-starter-security:2.2.2.RELEASE'
implementation 'org.springframework.boot:spring-boot-starter-webflux:2.2.2.RELEASE'
implementation 'org.springframework.security:spring-security-oauth2-client:5.2.1.RELEASE'
implementation 'com.google.guava:guava:28.1-jre'
implementation 'com.apollographql.apollo:apollo-runtime:1.2.2'
implementation 'com.apollographql.apollo:apollo-rx2-support:1.2.2'
}

		this.apolloClient = ApolloClient.builder().serverUrl(url)
												  .okHttpClient(okHttpClient())
												  .build();

	private OkHttpClient okHttpClient() {
		return new OkHttpClient.Builder()//.authenticator(new BearerTokenAuthenticator(tokenProvider()))
				  						 //.addInterceptor(new BearerTokenInterceptor(tokenProvider()))
				  						 .build();
	}

No customizations on either the ApolloClient or the okHttpClient. If I make the call with the okHttpClient directly, the app exits fine.

Call is simply made as (also tried the enqueue callback method):

		GetAllCustomersQuery query = GetAllCustomersQuery.builder().build();
		ApolloCall<GetAllCustomersQuery.Data> apolloCall = this.apolloClient.query(query);
		Observable<Response<Data>> observable = Rx2Apollo.from(apolloCall);
		return observable.blockingSingle().data().getAllCustomers();

[martinbonnin]

I've used Apollo in a command-line app that hanged because the Apollo client uses a ThreadPool and the JVM would not close until all threads terminated. I called System.exit(0) at the end of my main() to workaround that. Maybe it's a similar problem ?

[SledgeHammer01]

I've used Apollo in a command-line app that hanged because the Apollo client uses a ThreadPool and the JVM would not close until all threads terminated. I called System.exit(0) at the end of my main() to workaround that. Maybe it's a similar problem ?

Yes, it appears that there are extra threads blocking. Isn't this going to be an issue in any kind of application if there is no way to cleanly shutdown the thread pool?

[SledgeHammer01]

I've used Apollo in a command-line app that hanged because the Apollo client uses a ThreadPool and the JVM would not close until all threads terminated. I called System.exit(0) at the end of my main() to workaround that. Maybe it's a similar problem ?

Just for the heck of it, I tried .dispatcher(MoreExecutors.directExecutor()) on my ApolloClient builder which, from looking at the code, should disable the ThreadPool... still hangs... ugh... getting close to pulling the plug on this and just using WebClient.

[martinbonnin]

The corresponding OkHttp issue: square/okhttp#5542

In some other app of mine (without apollo), a similar issue was fixed by upgrading okhttp to 4.4.0. We should update okhttp. This will bring a kotlin-stdlib dependency but I think it's okay considering #1784

[tasomaniac]

@SledgeHammer01 can you check with Apollo 2.0? Thanks

[martinbonnin]

Maybe duplicate of #3619?

We've upgraded OkHttp to 4.x and this should not happen anymore. Can you try with Apollo Android 3 and let us know how that goes?

[martinbonnin]

Closing as obsolete. Please leave a message if you want us to reopen.