org.springframework.messaging.simp.SimpMessageSendingOperations Maven / Gradle / Ivy
/*
* Copyright 2002-2017 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.messaging.simp;
import java.util.Map;
import org.springframework.lang.Nullable;
import org.springframework.messaging.MessagingException;
import org.springframework.messaging.core.MessagePostProcessor;
import org.springframework.messaging.core.MessageSendingOperations;
/**
* A specialization of {@link MessageSendingOperations} with methods for use with
* the Spring Framework support for Simple Messaging Protocols (like STOMP).
*
* For more on user destinations see
* {@link org.springframework.messaging.simp.user.UserDestinationResolver
* UserDestinationResolver}.
*
*
Generally it is expected the user is the one authenticated with the
* WebSocket session (or by extension the user authenticated with the
* handshake request that started the session). However if the session is
* not authenticated, it is also possible to pass the session id (if known)
* in place of the user name. Keep in mind though that in that scenario,
* you must use one of the overloaded methods that accept headers making sure the
* {@link org.springframework.messaging.simp.SimpMessageHeaderAccessor#setSessionId
* sessionId} header has been set accordingly.
*
* @author Rossen Stoyanchev
* @since 4.0
*/
public interface SimpMessageSendingOperations extends MessageSendingOperations {
/**
* Send a message to the given user.
* @param user the user that should receive the message.
* @param destination the destination to send the message to.
* @param payload the payload to send
*/
void convertAndSendToUser(String user, String destination, Object payload) throws MessagingException;
/**
* Send a message to the given user.
* By default headers are interpreted as native headers (e.g. STOMP) and
* are saved under a special key in the resulting Spring
* {@link org.springframework.messaging.Message Message}. In effect when the
* message leaves the application, the provided headers are included with it
* and delivered to the destination (e.g. the STOMP client or broker).
*
If the map already contains the key
* {@link org.springframework.messaging.support.NativeMessageHeaderAccessor#NATIVE_HEADERS "nativeHeaders"}
* or was prepared with
* {@link org.springframework.messaging.simp.SimpMessageHeaderAccessor SimpMessageHeaderAccessor}
* then the headers are used directly. A common expected case is providing a
* content type (to influence the message conversion) and native headers.
* This may be done as follows:
*
* SimpMessageHeaderAccessor accessor = SimpMessageHeaderAccessor.create();
* accessor.setContentType(MimeTypeUtils.TEXT_PLAIN);
* accessor.setNativeHeader("foo", "bar");
* accessor.setLeaveMutable(true);
* MessageHeaders headers = accessor.getMessageHeaders();
* messagingTemplate.convertAndSendToUser(user, destination, payload, headers);
*
* Note: if the {@code MessageHeaders} are mutable as in
* the above example, implementations of this interface should take notice and
* update the headers in the same instance (rather than copy or re-create it)
* and then set it immutable before sending the final message.
* @param user the user that should receive the message (must not be {@code null})
* @param destination the destination to send the message to (must not be {@code null})
* @param payload the payload to send (may be {@code null})
* @param headers the message headers (may be {@code null})
*/
void convertAndSendToUser(String user, String destination, Object payload, Map headers)
throws MessagingException;
/**
* Send a message to the given user.
* @param user the user that should receive the message (must not be {@code null})
* @param destination the destination to send the message to (must not be {@code null})
* @param payload the payload to send (may be {@code null})
* @param postProcessor a postProcessor to post-process or modify the created message
*/
void convertAndSendToUser(String user, String destination, Object payload, MessagePostProcessor postProcessor)
throws MessagingException;
/**
* Send a message to the given user.
* See {@link #convertAndSend(Object, Object, java.util.Map)} for important
* notes regarding the input headers.
* @param user the user that should receive the message
* @param destination the destination to send the message to
* @param payload the payload to send
* @param headers the message headers
* @param postProcessor a postProcessor to post-process or modify the created message
*/
void convertAndSendToUser(String user, String destination, Object payload, @Nullable Map headers,
@Nullable MessagePostProcessor postProcessor) throws MessagingException;
}