PagedQuery.kt

fun <TData> pagedDataOf(nextPageStartingFrom: (start: Int) -> Flowable<PagedResponse<TData>>): Flowable<List<TData>> {
    return Flowable.generate<List<TData>, Int>(
            Callable<Int> { 0 },
            BiFunction<Int, Emitter<List<TData>>, Int> { index, emitter ->
                nextPageStartingFrom(index)
                        .doOnNext { page ->
                            if (!page.values.isEmpty()) {
                                emitter.onNext(page.values)
                            }

                            if (page.isLastPage) {
                                emitter.onComplete()
                            }
                        }
                        .map { data -> data.nextPageStart }
                        .blockingFirst()
            })
}