boot - SSE

boot - SSE 使用

sse(Server Sent Event)，直译为服务器发送事件，顾名思义，也就是客户端可以获取到服务器发送的事件

webflux 使用

@GetMapping("/stream-sse")
public Flux<ServerSentEvent<String>> streamEvents() {
    return Flux.interval(Duration.ofSeconds(1))
        .map(sequence -> ServerSentEvent.<String> builder()
             .id(String.valueOf(sequence))
             .event("periodic-event")
             .data("SSE - " + LocalTime.now().toString())
             .build());
}

@GetMapping(path = "/stream-flux", produces = MediaType.TEXT_EVENT_STREAM_VALUE)
public Flux<String> streamFlux() {
    return Flux.interval(Duration.ofSeconds(1))
        .map(sequence -> "Flux - " + LocalTime.now().toString());
}

spring-mvc 方式

@GetMapping("/stream-sse-mvc")
public SseEmitter streamSseMvc() {
    SseEmitter emitter = new SseEmitter();
    ExecutorService sseMvcExecutor = Executors.newSingleThreadExecutor();
    sseMvcExecutor.execute(() -> {
        try {
            for (int i = 0; true; i++) {
                SseEmitter.SseEventBuilder event = SseEmitter.event()
                    .data("SSE MVC - " + LocalTime.now().toString())
                    .id(String.valueOf(i))
                    .name("sse event - mvc");
                emitter.send(event);
                Thread.sleep(1000);
            }
        } catch (Exception ex) {
            emitter.completeWithError(ex);
        }
    });
    return emitter;
}