Add STOMP subscribe/unscubscribe ApplicationContext events

Issue: SPR-11813

Author: rstoyanchev

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

@@ -0,0 +1,71 @@
+/*
+ * 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 base class for events for a message received from a WebSocket client and
+ * parsed into a higher level sub-protocol (e.g. STOMP).
+ *
+ * @author Rossen Stoyanchev
+ * @since 4.0.3
+ */
+@SuppressWarnings("serial")
+public abstract class AbstractSubProtocolEvent 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
+	 */
+	protected AbstractSubProtocolEvent(Object source, Message<byte[]> message) {
+		super(source);
+		Assert.notNull(message, "'message' must not be null");
+		this.message = message;
+	}
+
+	/**
+	 * Return the Message associated with the event. Here is an example of
+	 * obtaining information about the session id or any headers in the
+	 * message:
+	 *
+	 * <pre class="code">
+	 * StompHeaderAccessor headers = StompHeaderAccessor.wrap(message);
+	 * headers.getSessionId();
+	 * headers.getSessionAttributes();
+	 * headers.getPrincipal();
+	 * </pre>
+	 *
+	 */
+	public Message<byte[]> getMessage() {
+		return this.message;
+	}
+
+
+	@Override
+	public String toString() {
+		return getClass().getSimpleName() + "[" + this.message + "]";
+	}
+}

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

@@ -17,9 +17,7 @@
 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
@@ -29,50 +27,15 @@
  * 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 {
+public class SessionConnectEvent extends AbstractSubProtocolEvent {
 
-	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;
+		super(source, message);
 	}
 
-	/**
-	 * Return the connect message.
-	 */
-	public Message<byte[]> getMessage() {
-		return this.message;
-	}
-
-
-	@Override
-	public String toString() {
-		return "SessionConnectEvent" + this.message;
-	}
 }

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

@@ -17,45 +17,22 @@
 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}.
+ * See {@link org.springframework.web.socket.messaging.SessionConnectEvent
+ * SessionConnectEvent}.
  *
  * @author Rossen Stoyanchev
  * @since 4.0.3
  */
 @SuppressWarnings("serial")
-public class SessionConnectedEvent extends ApplicationEvent {
+public class SessionConnectedEvent extends AbstractSubProtocolEvent {
 
-	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;
+		super(source, message);
 	}
 
-
-	@Override
-	public String toString() {
-		return "SessionConnectedEvent" + this.message;
-	}
 }

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

@@ -68,7 +68,7 @@ public CloseStatus getCloseStatus() {
 
 	@Override
 	public String toString() {
-		return "SessionDisconnectEvent[sessionId=" + this.sessionId +
+		return "SessionDisconnectEvent[sessionId=" + this.sessionId + ", " +
 				(this.status != null ? this.status.toString() : "closeStatus=null") + "]";
 	}
 }

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

@@ -0,0 +1,37 @@
+/*
+ * 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.messaging.Message;
+
+/**
+ * Event raised when a new WebSocket client using a Simple Messaging Protocol
+ * (e.g. STOMP) sends a subscription request.
+ *
+ * @author Rossen Stoyanchev
+ * @since 4.0.3
+ */
+@SuppressWarnings("serial")
+public class SessionSubscribeEvent extends AbstractSubProtocolEvent {
+
+
+	public SessionSubscribeEvent(Object source, Message<byte[]> message) {
+		super(source, message);
+	}
+
+}

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

@@ -0,0 +1,37 @@
+/*
+ * 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.messaging.Message;
+
+/**
+ * Event raised when a new WebSocket client using a Simple Messaging Protocol
+ * (e.g. STOMP) sends a request to remove a subscription.
+ *
+ * @author Rossen Stoyanchev
+ * @since 4.0.3
+ */
+@SuppressWarnings("serial")
+public class SessionUnsubscribeEvent extends AbstractSubProtocolEvent {
+
+
+	public SessionUnsubscribeEvent(Object source, Message<byte[]> message) {
+		super(source, message);
+	}
+
+}

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

@@ -219,8 +219,16 @@ public void handleMessageFromClient(WebSocketSession session,
 				headerAccessor.setUser(session.getPrincipal());
 				headerAccessor.setImmutable();
 
-				if (this.eventPublisher != null && StompCommand.CONNECT.equals(headerAccessor.getCommand())) {
-					publishEvent(new SessionConnectEvent(this, message));
+				if (this.eventPublisher != null) {
+					if (StompCommand.CONNECT.equals(headerAccessor.getCommand())) {
+						publishEvent(new SessionConnectEvent(this, message));
+					}
+					else if (StompCommand.SUBSCRIBE.equals(headerAccessor.getCommand())) {
+						publishEvent(new SessionSubscribeEvent(this, message));
+					}
+					else if (StompCommand.UNSUBSCRIBE.equals(headerAccessor.getCommand())) {
+						publishEvent(new SessionUnsubscribeEvent(this, message));
+					}
 				}
 
 				try {

spring-websocket/src/test/java/org/springframework/web/socket/messaging/StompSubProtocolHandlerTests.java

@@ -184,12 +184,24 @@ public void eventPublication() {
 		message = MessageBuilder.createMessage(EMPTY_PAYLOAD, headers.getMessageHeaders());
 		this.protocolHandler.handleMessageToClient(this.session, message);
 
+		headers = StompHeaderAccessor.create(StompCommand.SUBSCRIBE);
+		message = MessageBuilder.createMessage(EMPTY_PAYLOAD, headers.getMessageHeaders());
+		textMessage = new TextMessage(new StompEncoder().encode(message));
+		this.protocolHandler.handleMessageFromClient(this.session, textMessage, this.channel);
+
+		headers = StompHeaderAccessor.create(StompCommand.UNSUBSCRIBE);
+		message = MessageBuilder.createMessage(EMPTY_PAYLOAD, headers.getMessageHeaders());
+		textMessage = new TextMessage(new StompEncoder().encode(message));
+		this.protocolHandler.handleMessageFromClient(this.session, textMessage, this.channel);
+
 		this.protocolHandler.afterSessionEnded(this.session, CloseStatus.BAD_DATA, this.channel);
 
-		assertEquals("Unexpected events " + publisher.events, 3, publisher.events.size());
+		assertEquals("Unexpected events " + publisher.events, 5, publisher.events.size());
 		assertEquals(SessionConnectEvent.class, publisher.events.get(0).getClass());
 		assertEquals(SessionConnectedEvent.class, publisher.events.get(1).getClass());
-		assertEquals(SessionDisconnectEvent.class, publisher.events.get(2).getClass());
+		assertEquals(SessionSubscribeEvent.class, publisher.events.get(2).getClass());
+		assertEquals(SessionUnsubscribeEvent.class, publisher.events.get(3).getClass());
+		assertEquals(SessionDisconnectEvent.class, publisher.events.get(4).getClass());
 	}
 
 	@Test

src/asciidoc/index.adoc

@@ -38417,6 +38417,8 @@ to this event can wrap the contained message using `SimpMessageHeaderAccessor` o
 * `SessionConnectedEvent` -- published shortly after a `SessionConnectEvent` when the
 broker has sent a STOMP CONNECTED frame in response to the CONNECT. At this point the
 STOMP session can be considered fully established.
+* `SessionSubscribeEvent` -- published when a new STOMP SUBSCRIBE is received.
+* `SessionUnsubscribeEvent` -- published when a new STOMP UNSUBSCRIBE is received.
 * `SessionDisconnectEvent` -- published when a STOMP session ends. The DISCONNECT may
 have been sent from the client or it may also be automatically generated when the
 WebSocket session is closed. In some cases this event may be published more than once