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kotlinlang

Hey I am getting `JobCancellationException` and I am not sure what is the reason. My only hypothesis is that I am starting and canceling multiple times function that is in suspended state :thinking_face: but honestly I am not sure… Can somebody throw more light on this? What is the reason for throwing this exception?

<@U16NLGHQ8> Do you use channels with offer or poll, or do you use async without a local wrapping `coroutineScope { ... }` for structured concurrency?

<@U3ZLHBTLG> I am running coroutime like this:

```
val job:Job? = null
fun getQuote() {
    job?.cancel()

    job CoroutineScope(<http://Dispatchers.IO|Dispatchers.IO>).launch {
        delay(300)
        val result = repository.getQuote()
    }
}

class Repository(val retrofitQuoteService:RetrofitQuoteService) {
    suspend fun getQuote() {
        retrofitQuoteService.getQuoteAsync().await()
    }
}
```

`getQuote` can be called multiple times as this is called while user types in text input - called each time text input changes

<@U16NLGHQ8> Your `getQuote()` suspend function throws if there's a network issue or an unsuccessful response received. You need to catch it at call site (here, a `try`/`catch` in your `launch` block).

BTW, for general knowledge, you can (should) ask it on StackOverflow, post the link here, and I'll anwser it.

This is simplified version of the code - the problem is that requests are 100% correct here (all return 200) and data is parsed correctly on each single call. This problem arrises only when `getQuote` function is called multiple times (I sniff underlying network requests and they are correct), so I try to understand the reason behind it.

Also `JobCancellationException` is as internal class so I cannot catch this exception explicitly. I need to get to core of this and understand why this happens.

<@U16NLGHQ8> No, network can fail which throws. A `JobCancellationException` is always the sign of an uncaught exception, usually happening in a `launch` or `async` block.

A `JobCancellationException` is thrown when you cancel the job via `job.cancel()`

Where are you "getting JobCancellationException"? Is it in your logs as an uncaught exception? The `delay` inside of your `launch` block will throw that exception if the job is cancelled before your function resumes to your repository