如何提出真正的流量请求？

Question

我从Spring-Boot开始学习Webflux。我了解到，对于RestController的endpoint，您可以定义一个流量请求体，在这里我期望一个真正的流量流，也就是说，整个请求的各个部分一个接一个地出现，这些部分也可以一个接一个地处理。然而，在用客户端和服务器构建了一个小示例后，我无法让它像预期的那样工作。

@PostMapping("/digest")
    public Flux<String> digest(@RequestBody Flux<String> text) {
        continuousMD5.reset();
        return text.log("server.request.").map(piece -> continuousMD5.update(piece)).log("server.response.");
    }

@PostConstruct
    private void init() {
        webClient = webClientBuilder.baseUrl(reactiveServerUrl).build();
    }

@PostMapping(value = "/send", consumes = MediaType.TEXT_PLAIN_VALUE)
    public Flux<String> send(@RequestBody Flux<String> text) {
        return webClient.post()
            .uri("/digest")
            .accept(MediaType.TEXT_PLAIN)
            .body(text.log("client.request."), String.class)
            .retrieve().bodyToFlux(String.class).log("client.response.");
    }

for i in $(seq 1 100); do echo "The message $i"; done | http POST :8080/send  Content-Type:text/plain

2019-05-09 17:02:08.604  INFO 3462 --- [ctor-http-nio-2] client.response.Flux.MonoFlatMapMany.2   : onSubscribe(MonoFlatMapMany.FlatMapManyMain)
2019-05-09 17:02:08.606  INFO 3462 --- [ctor-http-nio-2] client.response.Flux.MonoFlatMapMany.2   : request(1)
2019-05-09 17:02:08.649  INFO 3462 --- [ctor-http-nio-6] client.request.Flux.SwitchIfEmpty.1      : onSubscribe(FluxSwitchIfEmpty.SwitchIfEmptySubscriber)
2019-05-09 17:02:08.650  INFO 3462 --- [ctor-http-nio-6] client.request.Flux.SwitchIfEmpty.1      : request(32)
2019-05-09 17:02:08.674  INFO 3462 --- [ctor-http-nio-2] client.request.Flux.SwitchIfEmpty.1      : onNext(The message 1)
2019-05-09 17:02:08.676  INFO 3462 --- [ctor-http-nio-2] client.request.Flux.SwitchIfEmpty.1      : request(1)
2019-05-09 17:02:08.676  INFO 3462 --- [ctor-http-nio-2] client.request.Flux.SwitchIfEmpty.1      : onNext(The message 2)
...
2019-05-09 17:02:08.710  INFO 3462 --- [ctor-http-nio-2] client.request.Flux.SwitchIfEmpty.1      : onNext(The message 100)
2019-05-09 17:02:08.710  INFO 3462 --- [ctor-http-nio-6] client.request.Flux.SwitchIfEmpty.1      : request(1)
2019-05-09 17:02:08.710  INFO 3462 --- [ctor-http-nio-6] client.request.Flux.SwitchIfEmpty.1      : request(1)
2019-05-09 17:02:08.710  INFO 3462 --- [ctor-http-nio-6] client.request.Flux.SwitchIfEmpty.1      : request(1)
2019-05-09 17:02:08.711  INFO 3462 --- [ctor-http-nio-2] client.request.Flux.SwitchIfEmpty.1      : onComplete()
2019-05-09 17:02:08.711  INFO 3462 --- [ctor-http-nio-6] client.request.Flux.SwitchIfEmpty.1      : request(1)
2019-05-09 17:02:08.711  INFO 3462 --- [ctor-http-nio-6] client.request.Flux.SwitchIfEmpty.1      : request(1)
2019-05-09 17:02:08.860  INFO 3462 --- [ctor-http-nio-6] client.response.Flux.MonoFlatMapMany.2   : onNext(CSubeSX3yIVP2CD6FRlojg==)
2019-05-09 17:02:08.862  INFO 3462 --- [ctor-http-nio-6] client.response.Flux.MonoFlatMapMany.2   : onComplete()
^C2019-05-09 17:02:47.393  INFO 3462 --- [ctor-http-nio-6] client.request.Flux.SwitchIfEmpty.1      : cancel()

但在服务器日志中：

2019-05-09 17:02:08.811  INFO 3475 --- [ctor-http-nio-2] server.request.Flux.SwitchIfEmpty.1      : onSubscribe(FluxSwitchIfEmpty.SwitchIfEmptySubscriber)
2019-05-09 17:02:08.813  INFO 3475 --- [ctor-http-nio-2] server.response.Flux.Map.2               : onSubscribe(FluxMap.MapSubscriber)
2019-05-09 17:02:08.814  INFO 3475 --- [ctor-http-nio-2] server.response.Flux.Map.2               : request(1)
2019-05-09 17:02:08.814  INFO 3475 --- [ctor-http-nio-2] server.request.Flux.SwitchIfEmpty.1      : request(1)
2019-05-09 17:02:08.838  INFO 3475 --- [ctor-http-nio-2] server.request.Flux.SwitchIfEmpty.1      : onNext(The message 1The message 2The message 3The message 4The message 5The message 6The message 7The message 8The message 9The message 10The message 11The message 12The message 13The message 14The message 15The message 16The message 17The message 18The message 19The message 20The message 21The message 22The message 23The message 24The message 25The message 26The message 27The message 28The message 29The message 30The message 31The message 32The message 33The message 34The message 35The message 36The message 37The message 38The message 39The message 40The message 41The message 42The message 43The message 44The message 45The message 46The message 47The message 48The message 49The message 50The message 51The message 52The message 53The message 54The message 55The message 56The message 57The message 58The message 59The message 60The message 61The message 62The message 63The message 64The message 65The message 66The message 67The message 68The message 69The message 70The message 71The message 72The message 73The message 74The message 75The message 76The message 77The message 78The message 79The message 80The message 81The message 82The message 83The message 84The message 85The message 86The message 87The message 88The message 89The message 90The message 91The message 92The message 93The message 94The message 95The message 96The message 97The message 98The message 99The message 100)
2019-05-09 17:02:08.840  INFO 3475 --- [ctor-http-nio-2] server.response.Flux.Map.2               : onNext(CSubeSX3yIVP2CD6FRlojg==)
2019-05-09 17:02:08.852  INFO 3475 --- [ctor-http-nio-2] server.response.Flux.Map.2               : request(32)
2019-05-09 17:02:08.852  INFO 3475 --- [ctor-http-nio-2] server.request.Flux.SwitchIfEmpty.1      : request(32)
2019-05-09 17:02:08.852  INFO 3475 --- [ctor-http-nio-2] server.request.Flux.SwitchIfEmpty.1      : onComplete()
2019-05-09 17:02:08.852  INFO 3475 --- [ctor-http-nio-2] server.response.Flux.Map.2               : onComplete()
2019-05-09 17:02:47.394  INFO 3475 --- [ctor-http-nio-2] server.response.Flux.Map.2               : cancel()
2019-05-09 17:02:47.394  INFO 3475 --- [ctor-http-nio-2] server.request.Flux.SwitchIfEmpty.1      : cancel()

我看到所有的文本片断都同时到达服务器，因此作为流量流中的一个大元素进行处理（还可以验证只计算了一个MD5散列而不是100）。

我所期望的是，服务器还将从客户机接收文本片段作为流量流中的元素，否则对于服务器来说，它不是真正的反应，而只是一个普通的阻塞请求。

Answer 1

如果要实现流式效果，可以：

• 使用支持流的不同内容类型-application/stream+JSON。查看以下SO线程：Spring WebFlux Flux行为与非流应用程序/json
• 将底层协议更改为更适合流模型的协议，例如WebSockets。https://howtodoinjava.com/spring-webflux/reactive-websockets/