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kotlinlang

I have a question about Server-Sent Events clients and Kotlin. This is currently how I consume events from my server. :thread:

This is how I make my SSE call from the client today:
```private fun listenForEvents(query: String): Flow&lt;EventData&gt; = callbackFlow {
    httpClient.sse(
        urlString = EVENT_URL,
        request = {
            contentType(ContentType.Application.Json)
            parameter("query", query)
        },
    ) {
        incoming.collect { event -&gt;
            event.data?.let {
                Json.decodeFromString&lt;EventData&gt;(it)?.let { eventData -&gt;
                    send(eventData)
                }
            }
        }
    }
}```

However, I'm not too fond of doing a `collect()` inside the `callbackFlow {}`, so I'm wondering if there's a way to pass the `incoming` flow back to the caller instead?

You probably want to use the `serverSentEventsSession` API which returns a `ClientSSESession` or `ClientSSESessionWithDeserialization` and you can access `incoming` on the returned value.

That's what I got there. `httpClient.sse()` gives me a `ClientSSESession` and that's where I do `incoming.collect`.

Not sure if this is an issue, but right now I'm doing a `collect()` inside a `callbackFlow` , and I feel there should be a more straightforward way to return `ClientSSESession.incoming` to the caller of `listenForEvents()`.

`client.sse` takes a lambda for `ClientSSESession` but `client.serverSentEventsSession` returns `ClientSSESession`.

Here a complete snippet:
```val session = httpClient.serverSentEventsSession(urlString = EVENT_URL) {
    contentType(ContentType.Application.Json)
    parameter("query", "...")
}
try {
    session.incoming.collect {  }
} finally {
    session.cancel()
}```
I'm not sure if the `try/finally` and `session.cancel()` is actually necessary since a failure in `collect` should cancel the flow, and cancelling the outer `Job` should also cancel the `incoming` but I'd need to test/verify/double-check that :sweat_smile: