batcher goroutine

func batcher[T any](in chan T, out chan []T, batchSize int, timeout time.Duration) {
	for {
		batch := make([]T, 0, batchSize)
		t := time.After(timeout)
		for batchReady := false; !batchReady; {
			select {
			case e := <-in:
				batch = append(batch, e)
				if len(batch) == batchSize {
					batchReady = true
				}
			case <-t:
				if len(batch) > 0 {
					batchReady = true
					break
				}
				t = time.After(timeout)
			}
			if batchReady == true {
				out <- batch
			}
		}
	}
}