- Hands-On Reactive Programming in Spring 5
- Oleh Dokuka Igor Lozynskyi
- 306字
- 2021-07-23 16:36:29
Vert.x adjustments
Along with the transformation of RxJava, the rest of the reactive libraries and frameworks vendors have also started adopting the Reactive Streams specification. Following the specification, Vert.x included an additional module which provides support for the Reactive Streams API. The following example demonstrates this addition:
... // (1)
.requestHandler(request -> { //
ReactiveReadStream<Buffer> rrs = // (2)
ReactiveReadStream.readStream(); //
HttpServerResponse response = request.response(); //
Flowable<Buffer> logs = Flowable // (3)
.fromPublisher(logsService.stream()) //
.map(Buffer::buffer) //
.doOnTerminate(response::end); //
logs.subscribe(rrs); // (4)
response.setStatusCode(200); // (5)
response.setChunked(true); //
response.putHeader("Content-Type", "text/plain"); //
response.putHeader("Connection", "keep-alive"); //
Pump.pump(rrs, response) // (6)
.start(); //
})
...
The key is as follows:
- This is the request handler declaration. This is a generic request handler that allows handling any requests sent to the server.
- This is the Subscriber and HTTP response declaration. Here ReactiveReadStream implements both org.reactivestreams.Subscriber and ReadStream, which allows transforming any Publisher to the source of data compatible with a Vert.x API.
- This is the processing flow declaration. In that example, we refer to the new Reactive Streams-based LogsService interface, and to write a functional transformation of the elements in the stream we use the Flowable API from RxJava 2.x.
- This is the subscription stage. Once the processing flow is declared, we may subscribe ReactiveReadStream to the Flowable.
- This is a response preparation stage.
- This is the final response being sent to the client. Here, the Pump class plays an important role in a sophisticated mechanism of backpressure control to prevent the underlying WriteStream buffer from getting too full.
As we can see, Vert.x does not provide a fluent API for writing a stream of element processing. However, it provides an API that allows converting any Publisher to the Vert.x API, keeping the sophisticated backpressure management from Reactive Streams in place.
推薦閱讀
- 黑客攻防實戰(zhàn)技術(shù)完全手冊:掃描、嗅探、入侵與防御
- 微商之道
- 走進物聯(lián)網(wǎng)
- Oracle SOA Suite 11g Performance Tuning Cookbook
- Web Application Development with R Using Shiny
- Getting Started with Grunt:The JavaScript Task Runner
- Learning Swift(Second Edition)
- SAE原理與網(wǎng)絡(luò)規(guī)劃
- 物聯(lián)網(wǎng)工程導(dǎo)論(第3版)
- 設(shè)備監(jiān)控技術(shù)詳解
- Dart Cookbook
- 中國互聯(lián)網(wǎng)發(fā)展報告2021
- 5G非正交多址接入技術(shù):理論、算法與實現(xiàn)
- 無線傳感器網(wǎng)絡(luò)定位方法及應(yīng)用
- 加密與解密實戰(zhàn)全攻略