INT-3511: Document WebSocket Support

JIRA: https://jira.spring.io/browse/INT-3511

Add note about Broker destinations

Doc Polishing

INT-3511: Fix 'useBroker' Docs and provide compatibility with SF 4.1.1

Author: artembilan

spring-integration-websocket/src/main/java/org/springframework/integration/websocket/IntegrationWebSocketContainer.java

@@ -26,17 +26,13 @@
 import org.apache.commons.logging.LogFactory;
 
 import org.springframework.beans.factory.DisposableBean;
-import org.springframework.context.ApplicationEvent;
-import org.springframework.context.ApplicationEventPublisher;
-import org.springframework.context.ApplicationEventPublisherAware;
 import org.springframework.util.Assert;
 import org.springframework.web.socket.CloseStatus;
 import org.springframework.web.socket.SubProtocolCapable;
 import org.springframework.web.socket.WebSocketHandler;
 import org.springframework.web.socket.WebSocketMessage;
 import org.springframework.web.socket.WebSocketSession;
 import org.springframework.web.socket.handler.ConcurrentWebSocketSessionDecorator;
-import org.springframework.web.socket.messaging.SessionDisconnectEvent;
 
 /**
  * The high-level 'connection factory pattern' contract over low-level Web-Socket
@@ -59,7 +55,7 @@
  * @see org.springframework.integration.websocket.inbound.WebSocketInboundChannelAdapter
  * @see org.springframework.integration.websocket.outbound.WebSocketOutboundMessageHandler
  */
-public abstract class IntegrationWebSocketContainer implements ApplicationEventPublisherAware, DisposableBean {
+public abstract class IntegrationWebSocketContainer implements DisposableBean {
 
 	protected final Log logger = LogFactory.getLog(this.getClass());
 
@@ -75,8 +71,6 @@ public abstract class IntegrationWebSocketContainer implements ApplicationEventP
 
 	private volatile int sendBufferSizeLimit = 512 * 1024;
 
-	private ApplicationEventPublisher eventPublisher;
-
 	public void setSendTimeLimit(int sendTimeLimit) {
 		this.sendTimeLimit = sendTimeLimit;
 	}
@@ -85,11 +79,6 @@ public void setSendBufferSizeLimit(int sendBufferSizeLimit) {
 		this.sendBufferSizeLimit = sendBufferSizeLimit;
 	}
 
-	@Override
-	public void setApplicationEventPublisher(ApplicationEventPublisher applicationEventPublisher) {
-		this.eventPublisher = applicationEventPublisher;
-	}
-
 	public void setMessageListener(WebSocketListener messageListener) {
 		Assert.state(this.messageListener == null || this.messageListener == messageListener,
 				"'messageListener' is already configured");
@@ -146,15 +135,6 @@ public void destroy() throws Exception {
 		this.sessions.clear();
 	}
 
-	private void publishEvent(ApplicationEvent event) {
-		try {
-			this.eventPublisher.publishEvent(event);
-		}
-		catch (Throwable ex) {
-			logger.error("Error while publishing " + event, ex);
-		}
-	}
-
 	/**
 	 * An internal {@link WebSocketHandler} implementation to be used with native
 	 * Web-Socket containers.
@@ -192,9 +172,6 @@ public void afterConnectionClosed(WebSocketSession session, CloseStatus closeSta
 				if (IntegrationWebSocketContainer.this.messageListener != null) {
 					IntegrationWebSocketContainer.this.messageListener.afterSessionEnded(session, closeStatus);
 				}
-				else if (IntegrationWebSocketContainer.this.eventPublisher != null) {
-					publishEvent(new SessionDisconnectEvent(this, session.getId(), closeStatus));
-				}
 			}
 		}
 
@@ -203,10 +180,8 @@ public void handleTransportError(WebSocketSession session, Throwable exception)
 			WebSocketSession removed = IntegrationWebSocketContainer.this.sessions.remove(session.getId());
 			if (removed != null) {
 				IntegrationWebSocketContainer.this.sessions.remove(session.getId());
-				if (IntegrationWebSocketContainer.this.eventPublisher != null) {
-					publishEvent(new SessionErrorEvent(this, session.getId(), exception));
-				}
 			}
+			throw new Exception(exception);
 		}
 
 		@Override

spring-integration-websocket/src/main/java/org/springframework/integration/websocket/SessionErrorEvent.java

@@ -234,7 +234,8 @@
 								</xsd:documentation>
 								<xsd:appinfo>
 									<tool:annotation kind="ref">
-										<tool:expected-type type="org.springframework.web.socket.sockjs.frame.SockJsMessageCodec"/>
+										<tool:expected-type
+												type="org.springframework.web.socket.sockjs.frame.SockJsMessageCodec"/>
 									</tool:annotation>
 								</xsd:appinfo>
 							</xsd:annotation>
@@ -357,19 +358,18 @@
 					<xsd:attribute name="payload-type" type="xsd:string">
 						<xsd:annotation>
 							<xsd:documentation source="java:java.lang.Class">
-								Fully qualified name of the java type for the target `payload`
+								Fully qualified name of the java type for the target 'payload'
 								to convert from the incoming WebSocketMessage.
 							</xsd:documentation>
 						</xsd:annotation>
 					</xsd:attribute>
 					<xsd:attribute name="use-broker" default="false">
 						<xsd:annotation>
 							<xsd:documentation>
-								Flag to indicate if this adapter will send non-MESSAGE type WebSocketMessages
-								and messages with broker destinations to the `AbstractBrokerMessageHandler`
+								Flag to indicate if this adapter will send non-MESSAGE type 'WebSocketMessage's
+								and messages with broker destinations to the 'AbstractBrokerMessageHandler'
 								from the application context.
-								If the `AbstractBrokerMessageHandler` bean isn't present the warn log is emitted
-								and adapter behaviour is falling back to default like this attribute is 'false'.
+								The 'Broker Relay' configuration is required when 'use-broker' is 'true'.
 								This attribute is used only on server side. On client side it is ignored.
 								Defaults to 'false'.
 							</xsd:documentation>
@@ -441,7 +441,7 @@
 			<xsd:annotation>
 				<xsd:documentation>
 					Flag to indicate if the default converters should be registered after any custom
-					converters. This flag is used only if message-converters
+					converters. This flag is used only if 'message-converters'
 					are provided, otherwise all default converters will be registered.
 					Defaults to 'false'.
 				</xsd:documentation>

spring-integration-websocket/src/main/resources/org/springframework/integration/websocket/config/spring-integration-websocket-4.1.xsd

@@ -882,8 +882,7 @@ then you should simply provide an implementation of the <classname>ReleaseStrate
 	</section>
 
   <section id="reaper">
-    <title id="reaper">Managing State in an Aggregator:
-    MessageGroupStore</title>
+    <title>Managing State in an Aggregator: MessageGroupStore</title>
 
     <para>Aggregator (and some other patterns in Spring Integration) is a
     stateful pattern that requires decisions to be made based on a group of

src/reference/docbook/aggregator.xml

@@ -144,6 +144,7 @@
       <xi:include href="./syslog.xml"/>
       <xi:include href="./ip.xml"/>
       <xi:include href="./twitter.xml"/>
+      <xi:include href="./web-sockets.xml"/>
       <xi:include href="./ws.xml"/>
 	  <xi:include href="./xml.xml"/>
 	  <xi:include href="./xmpp.xml"/>