Spring WebFlux和WebSocket

Question

我正在尝试向使用Spring的现有应用程序添加WebSocket功能。它使用：

服务jsp页面的2.2.1.RELEASE

• Tomcat container

• Configured

当我试图通过JavaScript连接到它时(从jsp页面中)，我收到的错误是“WebSocket握手期间失败:错误:意外响应代码: 404”。

我注意到，如果我创建一个控制器类，映射url '/ws/event-emitter‘(映射在我的websocket配置中)，接受GET请求，当它试图打开websocket连接时，它会接收来自Javascript调用的请求，这使我更加困惑。

我遗漏了什么？

在阅读了Internet上的一些教程之后，我将配置设置如下：

<?xml version="1.0" encoding="UTF-8"?>

">https://maven.apache.org/xsd/maven-4.0.0.xsd"> 4.0.0 org.springframework.boot spring-启动器-父程序2.2.1.starter br.com.samsung监视器0.0.1-快照监视器健康检查监视器

<properties>
    <java.version>1.8</java.version>
</properties>

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-devtools</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-actuator</artifactId>
    </dependency>
    <!-- 
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-security</artifactId>
    </dependency>
     -->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-webflux</artifactId>
    </dependency>
    <dependency>
        <groupId>org.apache.tomcat.embed</groupId>
        <artifactId>tomcat-embed-jasper</artifactId>
        <scope>provided</scope>
    </dependency>
    <dependency>
        <groupId>org.projectreactor</groupId>
        <artifactId>reactor-spring</artifactId>
        <version>1.0.1.RELEASE</version>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-mail</artifactId>
    </dependency>

    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
        <exclusions>
            <exclusion>
                <groupId>org.junit.vintage</groupId>
                <artifactId>junit-vintage-engine</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
    <dependency>
        <groupId>org.springframework.security</groupId>
        <artifactId>spring-security-test</artifactId>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>com.microsoft.sqlserver</groupId>
        <artifactId>mssql-jdbc</artifactId>
        <scope>test</scope>
    </dependency>
    <!-- MongoDB -->
    <dependency>
        <groupId>org.springframework.data</groupId>
        <artifactId>spring-data-mongodb</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.data</groupId>
        <artifactId>spring-data-releasetrain</artifactId>
        <version>Lovelace-SR9</version>
        <type>pom</type>
        <scope>import</scope>
    </dependency>
</dependencies>

<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
        </plugin>
    </plugins>
</build>

​

@Configuration

公共类ReactiveWebSocketConfiguration {

@Autowired
private WebSocketHandler webSocketHandler;

@Bean
public HandlerMapping webSocketHandlerMapping() {
    Map<String, WebSocketHandler> map = new HashMap<>();
    map.put("/ws/event-emitter", webSocketHandler);

    SimpleUrlHandlerMapping handlerMapping = new SimpleUrlHandlerMapping();
    handlerMapping.setOrder(Ordered.HIGHEST_PRECEDENCE);
    handlerMapping.setUrlMap(map);
    return handlerMapping;
}

@Bean
public WebSocketHandlerAdapter handlerAdapter(WebSocketService webSocketService) {
    return new WebSocketHandlerAdapter(webSocketService);
}

@Bean
public WebSocketService webSocketService() {
    TomcatRequestUpgradeStrategy strategy = new TomcatRequestUpgradeStrategy();
    strategy.setMaxSessionIdleTimeout(0L);
    return new HandshakeWebSocketService(strategy);
}

}

@Component公共类ReactiveWebSocketHandler实现WebSocketHandler {

private static final ObjectMapper json = new ObjectMapper();

private Flux<String> eventFlux = Flux.generate(sink -> {
    Event event = new Event(randomUUID().toString(), now().toString());
    try {
        sink.next(json.writeValueAsString(event));
    } catch (JsonProcessingException e) {
        sink.error(e);
    }
});

private Flux<String> intervalFlux = Flux.interval(Duration.ofMillis(1000L))
  .zipWith(eventFlux, (time, event) -> event);

@Override
public Mono<Void> handle(WebSocketSession webSocketSession) {
    return webSocketSession.send(intervalFlux
      .map(webSocketSession::textMessage))
      .and(webSocketSession.receive()
        .map(WebSocketMessage::getPayloadAsText).log());
}

}

​

		<script>
		    var clientWebSocket = new WebSocket("ws://localhost:6600/ws/event-emitter");
		    clientWebSocket.onopen = function() {
		        console.log("clientWebSocket.onopen", clientWebSocket);
		        console.log("clientWebSocket.readyState", "websocketstatus");
		        clientWebSocket.send("event-me-from-browser");
		    }
		    clientWebSocket.onclose = function(error) {
		        console.log("clientWebSocket.onclose", clientWebSocket, error);
		        events("Closing connection");
		    }
		    clientWebSocket.onerror = function(error) {
		        console.log("clientWebSocket.onerror", clientWebSocket, error);
		        events("An error occured");
		    }
		    clientWebSocket.onmessage = function(error) {
		        console.log("clientWebSocket.onmessage", clientWebSocket, error);
		        events(error.data);
		    }
		    function events(responseEvent) {
		        document.querySelector(".events").innerHTML += responseEvent + "<br>";
		    }
		</script>

​

Answer 1

我可以让它工作，消除spring-启动程序-web和tomcat-嵌入-jasper依赖。我想春-启动-启动-网络可能与春-启动-启动-网络流量相冲突。

此外，我还将ReactiveWebSocketConfiguration类更改为使用ReactorNettyRequestUpgradeStrategy而不是TomcatRequestUpgradeStrategy设置WebSocketService bean。

@Bean
public WebSocketService webSocketService() {
    return new HandshakeWebSocketService(new ReactorNettyRequestUpgradeStrategy());
}

在这些更改之后，我的jsp页面停止工作，因为我的web容器从Tomcat更改为。我不得不使用Thymeleaf (添加了spring-boot-starter依赖项，配置它的基本结构并将我的页面转换为.html文件)，而不是传统的jsp。

由于时间限制，我选择了从传统的jsp改为Thymeleaf，因为我的应用程序只有很少的简单页面。

我用所有这些配置创建了一个非常简单的项目，包括一个通过javascript连接到websocket的虚拟页面。

https://github.com/atilio-araujo/spring-webflux-websocket

Answer 2

Spring WebFlux WebSocket：

只是为那些试图用websocket实现webflux的人添加这个答案。

1. OP由于某种原因同时具有web和webflux依赖关系。但是，您只需要only.
2. Implement依赖WebFlux，一个WebSocketHandler

    @Service
    public class WebFluxWebSocketHandler implements WebSocketHandler {
    
        @Override
        public Mono<Void> handle(WebSocketSession webSocketSession) {
            Flux<WebSocketMessage> stringFlux = webSocketSession.receive()
                    .map(WebSocketMessage::getPayloadAsText)
                    .map(String::toUpperCase)
                    .map(webSocketSession::textMessage);
            return webSocketSession.send(stringFlux);
        }
    
    }

1. 添加了路径处理程序映射.这里，处理程序是websockethandler.

的一个实例

     @Bean
       public HandlerMapping handlerMapping(){
           Map<String, WebFluxWebSocketHandler> handlerMap = Map.of(
                   "/test", handler
           );
           return new SimpleUrlHandlerMapping(handlerMap, 1);
       }

就这样!现在客户端应该能够连接到ws://localhost:8080/test

查看这里获取更多信息- https://www.vinsguru.com/spring-webflux-websocket/