Incomplete chunked result

Question

The problem is when I return chunked response following documentation with a number of random lines, not all of these lines appear in browser (Google Chrome, Postman). E.g. if I send 8192 lines the browser will show only ~7k or even ~4k. My goal is to generate large CSV file using this kind of approach.

public Result test() {
    var source = Source.<ByteString>actorRef(256, OverflowStrategy.dropNew())
            .mapMaterializedValue(actor -> {
                new Thread(new MyRunnable(actor)).start();
                return NotUsed.getInstance();
            });

    return ok().chunked(source);
}

// ------

public class MyRunnable implements Runnable {

    private final ActorRef actor;

    public MyRunnable(ActorRef actor) {
        this.actor = actor;
    }

    public void run() {
        for (var i = 0; i < 1024 * 8; i++) {
            var line = String.format("%d some data goes here\n", i + 1);
            actor.tell(ByteString.fromString(line), null);
        }

        actor.tell(new Status.Success(NotUsed.getInstance()), null);
    }

}

Answer 1

Specify the content-length header as it seems play framework don't do it correctly .

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