kotlinx.coroutines.JobCancellationException: Job was cancelled;

[msya]

Summary

I am getting a kotlinx.coroutines.JobCancellationException: Job was cancelled; job=StandaloneCoroutine{Cancelled} exception when I use the toFlow method on the Apollo client.

Description

This repo https://github.com/msya/ApolloAndroidPlayground has an example app that shows the problem. I have a repo that creates an Apollo client and uses the toFlow extension to get the Flow.

class Repo {

    fun getData(): Flow<Response<TestQuery.Data>> {
        val client = ApolloClient.builder().serverUrl("https://api.kivaws.org/graphql").build()
        return client.query(TestQuery.builder().build()).toFlow()
    }
}

I also have a ViewModel that launch a coroutines in the view model scope. In this coroutine, I am collecting from the Flow.

class MyViewModel: ViewModel() {

    private val repo = Repo()

    val scope = CoroutineScope(Dispatchers.Main)

    fun getData() {
        scope.launch {
            repo.getData()
                .collect {
                    println(it)
                }
        }
    }

    fun cancel() {
        scope.cancel()
    }

}

However, if I call cancel on the Job returned by the coroutine. I am getting the cancellation exception - kotlinx.coroutines.JobCancellationException: Job was cancelled; job=StandaloneCoroutine{Cancelled}. In the activity below, I am canceling the call explicitly on a button click.

class MainActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        val model: MyViewModel by viewModels()

        make_request?.setOnClickListener {
            model.getData()
        }

        cancel?.setOnClickListener {
            model.cancel()
        }

    }
}

I suspect this problem is due to the clone method in the callbackFlow in the toFlow extension. If you remove the clone method, the exception does not occur.

Version
1.3.2

[martinbonnin]

For some context, the clone was added to address this bug: #1986

[diegocunhawarren]

Hey @martinbonnin, looking the changes regarding this issue, the class ApolloSubscriptionCall has the same issue about emit when the channel is closed, I created a custom extension like yours and just fixed to me!

[CureleaAndrei]

Hi, found the same issue in ApolloCall<>.await(). I think there should be a scope.isActive check. What do you think ?

[martinbonnin]

@CureleaAndrei can you share your apollo version and the stacktrace?

[basithp]

@CureleaAndrei Facing the same issue on ApolloCall<>.await(). was it fixed. I am using the version "2.5.9"