Add session lifecycle ApplicationEvent's

Issue: SPR-11578

spring-websocket/src/main/java/org/springframework/web/socket/messaging/SessionConnectEvent.java

@@ -0,0 +1,78 @@
+/*
+ * Copyright 2002-2014 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.web.socket.messaging;
+
+
+import org.springframework.context.ApplicationEvent;
+import org.springframework.messaging.Message;
+import org.springframework.util.Assert;
+
+/**
+ * Event raised when a new WebSocket client using a Simple Messaging Protocol
+ * (e.g. STOMP) as the WebSocket sub-protocol issues a connect request.
+ *
+ * <p>Note that this is not the same as the WebSocket session getting established
+ * but rather the client's first attempt to connect within the the sub-protocol,
+ * for example sending the STOMP CONNECT frame.
+ *
+ * <p>The provided {@link #getMessage() message} can be examined to check
+ * information about the connected user, The session id, and any headers
+ * sent by the client, for STOMP check the class
+ * {@link org.springframework.messaging.simp.stomp.StompHeaderAccessor}.
+ * For example:
+ *
+ * <pre class="code">
+ * StompHeaderAccessor headers = StompHeaderAccessor.wrap(message);
+ * headers.getSessionId();
+ * headers.getSessionAttributes();
+ * headers.getPrincipal();
+ * </pre>
+ *
+ * @author Rossen Stoyanchev
+ * @since 4.0.3
+ */
+@SuppressWarnings("serial")
+public class SessionConnectEvent extends ApplicationEvent {
+
+	private final Message<byte[]> message;
+
+
+	/**
+	 * Create a new SessionConnectEvent.
+	 *
+	 * @param source the component that published the event (never {@code null})
+	 * @param message the connect message
+	 */
+	public SessionConnectEvent(Object source, Message<byte[]> message) {
+		super(source);
+		Assert.notNull(message, "'message' must not be null");
+		this.message = message;
+	}
+
+	/**
+	 * Return the connect message.
+	 */
+	public Message<byte[]> getMessage() {
+		return this.message;
+	}
+
+
+	@Override
+	public String toString() {
+		return "SessionConnectEvent: message=" + message;
+	}
+}

spring-websocket/src/main/java/org/springframework/web/socket/messaging/SessionConnectedEvent.java

@@ -0,0 +1,61 @@
+/*
+ * Copyright 2002-2014 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.web.socket.messaging;
+
+
+import org.springframework.context.ApplicationEvent;
+import org.springframework.messaging.Message;
+import org.springframework.util.Assert;
+
+/**
+ * A connected event represents the server response to a client's connect request.
+ * See {@link org.springframework.web.socket.messaging.SessionConnectEvent}.
+ *
+ * @author Rossen Stoyanchev
+ * @since 4.0.3
+ */
+@SuppressWarnings("serial")
+public class SessionConnectedEvent extends ApplicationEvent {
+
+	private final Message<byte[]> message;
+
+
+	/**
+	 * Create a new event.
+	 *
+	 * @param source the component that published the event (never {@code null})
+	 * @param message the connected message
+	 */
+	public SessionConnectedEvent(Object source, Message<byte[]> message) {
+		super(source);
+		Assert.notNull(message, "'message' must not be null");
+		this.message = message;
+	}
+
+	/**
+	 * Return the connected message.
+	 */
+	public Message<byte[]> getMessage() {
+		return this.message;
+	}
+
+
+	@Override
+	public String toString() {
+		return "SessionConnectedEvent: message=" + message;
+	}
+}

spring-websocket/src/main/java/org/springframework/web/socket/messaging/SessionDisconnectEvent.java

@@ -0,0 +1,74 @@
+/*
+ * Copyright 2002-2014 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.web.socket.messaging;
+
+
+import org.springframework.context.ApplicationEvent;
+import org.springframework.messaging.Message;
+import org.springframework.util.Assert;
+import org.springframework.web.socket.CloseStatus;
+
+/**
+ * Event raised when the session of a WebSocket client using a Simple Messaging
+ * Protocol (e.g. STOMP) as the WebSocket sub-protocol is closed.
+ *
+ * <p>Note that this event may be raised more than once for a single session and
+ * therefore event consumers should be idempotent and ignore a duplicate event..
+ *
+ * @author Rossen Stoyanchev
+ * @since 4.0.3
+ */
+@SuppressWarnings("serial")
+public class SessionDisconnectEvent extends ApplicationEvent {
+
+	private final String sessionId;
+
+	private final CloseStatus status;
+
+	/**
+	 * Create a new event.
+	 *
+	 * @param source the component that published the event (never {@code null})
+	 * @param sessionId the disconnect message
+	 * @param closeStatus
+	 */
+	public SessionDisconnectEvent(Object source, String sessionId, CloseStatus closeStatus) {
+		super(source);
+		Assert.notNull(sessionId, "'sessionId' must not be null");
+		this.sessionId = sessionId;
+		this.status = closeStatus;
+	}
+
+	/**
+	 * Return the session id.
+	 */
+	public String getSessionId() {
+		return this.sessionId;
+	}
+
+	/**
+	 * Return the status with which the session was closed.
+	 */
+	public CloseStatus getCloseStatus() {
+		return this.status;
+	}
+
+	@Override
+	public String toString() {
+		return "SessionDisconnectEvent: sessionId=" + this.sessionId;
+	}
+}

spring-websocket/src/main/java/org/springframework/web/socket/messaging/StompSubProtocolHandler.java

@@ -28,6 +28,8 @@
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 
+import org.springframework.context.ApplicationEventPublisher;
+import org.springframework.context.ApplicationEventPublisherAware;
 import org.springframework.messaging.Message;
 import org.springframework.messaging.MessageChannel;
 import org.springframework.messaging.simp.SimpMessageType;
@@ -57,7 +59,7 @@
  * @author Andy Wilkinson
  * @since 4.0
  */
-public class StompSubProtocolHandler implements SubProtocolHandler {
+public class StompSubProtocolHandler implements SubProtocolHandler, ApplicationEventPublisherAware {
 
 	/**
 	 * The name of the header set on the CONNECTED frame indicating the name
@@ -76,6 +78,8 @@ public class StompSubProtocolHandler implements SubProtocolHandler {
 
 	private UserSessionRegistry userSessionRegistry;
 
+	private ApplicationEventPublisher eventPublisher;
+
 
 	/**
 	 * Configure the maximum size allowed for an incoming STOMP message.
@@ -120,6 +124,12 @@ public List<String> getSupportedProtocols() {
 		return Arrays.asList("v10.stomp", "v11.stomp", "v12.stomp");
 	}
 
+	@Override
+	public void setApplicationEventPublisher(ApplicationEventPublisher applicationEventPublisher) {
+		this.eventPublisher = applicationEventPublisher;
+	}
+
+
 	/**
 	 * Handle incoming WebSocket messages from clients.
 	 */
@@ -167,6 +177,11 @@ public void handleMessageFromClient(WebSocketSession session,
 				headers.setUser(session.getPrincipal());
 
 				message = MessageBuilder.withPayload(message.getPayload()).setHeaders(headers).build();
+
+				if (SimpMessageType.CONNECT.equals(headers.getMessageType()) && this.eventPublisher != null) {
+					this.eventPublisher.publishEvent(new SessionConnectEvent(this, message));
+				}
+
 				outputChannel.send(message);
 			}
 			catch (Throwable ex) {
@@ -231,6 +246,11 @@ else if (SimpMessageType.MESSAGE.equals(headers.getMessageType())) {
 
 		try {
 			message = MessageBuilder.withPayload(message.getPayload()).setHeaders(headers).build();
+
+			if (headers.getCommand() == StompCommand.CONNECTED && this.eventPublisher != null) {
+				this.eventPublisher.publishEvent(new SessionConnectedEvent(this, (Message<byte[]>) message));
+			}
+
 			byte[] bytes = this.stompEncoder.encode((Message<byte[]>) message);
 			TextMessage textMessage = new TextMessage(bytes);
 
@@ -329,6 +349,11 @@ public void afterSessionEnded(WebSocketSession session, CloseStatus closeStatus,
 		StompHeaderAccessor headers = StompHeaderAccessor.create(StompCommand.DISCONNECT);
 		headers.setSessionId(session.getId());
 		Message<?> message = MessageBuilder.withPayload(new byte[0]).setHeaders(headers).build();
+
+		if (this.eventPublisher != null) {
+			this.eventPublisher.publishEvent(new SessionDisconnectEvent(this, session.getId(), closeStatus));
+		}
+
 		outputChannel.send(message);
 	}
 

spring-websocket/src/main/java/org/springframework/web/socket/messaging/SubProtocolWebSocketHandler.java

@@ -28,6 +28,8 @@
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 
+import org.springframework.context.ApplicationEventPublisher;
+import org.springframework.context.ApplicationEventPublisherAware;
 import org.springframework.context.SmartLifecycle;
 import org.springframework.messaging.Message;
 import org.springframework.messaging.MessageChannel;
@@ -60,8 +62,8 @@
  * @author Andy Wilkinson
  * @since 4.0
  */
-public class SubProtocolWebSocketHandler
-		implements WebSocketHandler, SubProtocolCapable, MessageHandler, SmartLifecycle {
+public class SubProtocolWebSocketHandler implements WebSocketHandler,
+		SubProtocolCapable, MessageHandler, SmartLifecycle, ApplicationEventPublisherAware {
 
 	private final Log logger = LogFactory.getLog(SubProtocolWebSocketHandler.class);
 
@@ -84,6 +86,8 @@ public class SubProtocolWebSocketHandler
 
 	private volatile boolean running = false;
 
+	private ApplicationEventPublisher eventPublisher;
+
 
 	public SubProtocolWebSocketHandler(MessageChannel clientInboundChannel, SubscribableChannel clientOutboundChannel) {
 		Assert.notNull(clientInboundChannel, "ClientInboundChannel must not be null");
@@ -114,18 +118,24 @@ public List<SubProtocolHandler> getProtocolHandlers() {
 	 * Register a sub-protocol handler.
 	 */
 	public void addProtocolHandler(SubProtocolHandler handler) {
+
 		List<String> protocols = handler.getSupportedProtocols();
 		if (CollectionUtils.isEmpty(protocols)) {
 			logger.warn("No sub-protocols, ignoring handler " + handler);
 			return;
 		}
+
 		for (String protocol: protocols) {
 			SubProtocolHandler replaced = this.protocolHandlers.put(protocol, handler);
 			if ((replaced != null) && (replaced != handler) ) {
 				throw new IllegalStateException("Failed to map handler " + handler
 						+ " to protocol '" + protocol + "', it is already mapped to handler " + replaced);
 			}
 		}
+
+		if (handler instanceof ApplicationEventPublisherAware) {
+			((ApplicationEventPublisherAware) handler).setApplicationEventPublisher(this.eventPublisher);
+		}
 	}
 
 	/**
@@ -178,6 +188,10 @@ public int getSendBufferSizeLimit() {
 		return sendBufferSizeLimit;
 	}
 
+	@Override
+	public void setApplicationEventPublisher(ApplicationEventPublisher eventPublisher) {
+		this.eventPublisher = eventPublisher;
+	}
 
 	@Override
 	public boolean isAutoStartup() {