连接排空后打开新的连接。 Google云消息传递

我对Google Cloud Messaging有点新鲜。 我们一直在使用它几个月,但最近我们得到了“连接排水”信息。 发生这种情况时,所有通信都会停止

Google说:https://developer.android.com/google/gcm/ccs.html#response

当您收到CONNECTION_DRAINING消息时,应立即开始将消息发送到另一个CCS连接,并根据需要打开一个新连接。 但是,您应该保持原始连接处于打开状态,并继续接收可能通过连接发送的消息(并确认它们)--CSCS将在准备就绪后处理关闭连接。

我的问题是

  • 如果我手动打开一个新连接,如果我不关闭现有连接,它如何知道要使用哪个连接?
  • 如果同时发送6条消息,我该如何停止打开6个连接的方法? 或者我对此感到困惑?
  • 为什么连接耗尽会发生?
  • 我很惊讶这个例子中的代码还没有发挥作用。 它看起来像它几乎所有你需要的东西。 它是否已经在代码中完成了,我错过了它?

    我没有在我的代码中的主要方法,我用servlet作为触发器。 我的连接就像这样被初始化了

    @PostConstruct
        public void init() throws Exception{
            try {
                smackCcsClient.connect(Long.parseLong(env.getProperty("gcm.api")), env.getProperty("gcm.key"));
            }catch (IOException e ){
                e.printStackTrace();
            }catch(SmackException e){
                e.printStackTrace();
            }catch(XMPPException e){
                e.printStackTrace();
            }
        }
    

    但是在此之后,我再也不会碰到连接。 我是否处理了这个错误,是我应该更频繁地接触的东西,还是我需要跟踪的东西?

    _______________________在问题后加入______________________

    我在他们的示例代码中添加了一个连接以尝试重新初始化连接。 它看起来像这样:

    if ("CONNECTION_DRAINING".equals(controlType)) {
                connectionDraining = true;
                //Open new connection because old connection will be closing or is already closed.
                try {
                    connect(Long.parseLong(env.getProperty("gcm.api")), env.getProperty("gcm.key"));
                } catch (XMPPException e) {
                    e.printStackTrace();
                } catch (IOException e) {
                    e.printStackTrace();
                } catch (SmackException e) {
                    e.printStackTrace();
                }
    
            } else {
                logger.log(Level.INFO, "Unrecognized control type: %s. This could happen if new features are " + "added to the CCS protocol.",
                        controlType);
            }
    

    我已经编写了一个处理这种情况的代码(基本上将新的下游消息转移到一个新的连接)......未经彻底测试......

    import java.util.Deque;
    import java.util.HashMap;
    import java.util.Map;
    import java.util.concurrent.ConcurrentLinkedDeque;
    
    import javax.net.ssl.SSLSocketFactory;
    
    import org.jivesoftware.smack.ConnectionConfiguration;
    import org.jivesoftware.smack.ConnectionConfiguration.SecurityMode;
    import org.jivesoftware.smack.ConnectionListener;
    import org.jivesoftware.smack.PacketInterceptor;
    import org.jivesoftware.smack.PacketListener;
    import org.jivesoftware.smack.SmackException.NotConnectedException;
    import org.jivesoftware.smack.XMPPConnection;
    import org.jivesoftware.smack.filter.PacketTypeFilter;
    import org.jivesoftware.smack.packet.DefaultPacketExtension;
    import org.jivesoftware.smack.packet.Message;
    import org.jivesoftware.smack.packet.Packet;
    import org.jivesoftware.smack.packet.PacketExtension;
    import org.jivesoftware.smack.provider.PacketExtensionProvider;
    import org.jivesoftware.smack.provider.ProviderManager;
    import org.jivesoftware.smack.tcp.XMPPTCPConnection;
    import org.jivesoftware.smack.util.StringUtils;
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    import org.xmlpull.v1.XmlPullParser;
    
    import com.fasterxml.jackson.core.type.TypeReference;
    
    
    /**
     * Based on https://developer.android.com/google/gcm/ccs.html#smack
     * 
     * @author Abhinav.Dwivedi
     *
     */
    public class SmackCcsClient implements CcsClient {
        private static final Logger logger = LoggerFactory.getLogger(SmackCcsClient.class);
        private static final String GCM_SERVER = "gcm.googleapis.com";
        private static final int GCM_PORT = 5235;
        private static final String GCM_ELEMENT_NAME = "gcm";
        private static final String GCM_NAMESPACE = "google:mobile:data";
        private static volatile SmackCcsClient instance;
        static {
            ProviderManager.addExtensionProvider(GCM_ELEMENT_NAME, GCM_NAMESPACE, new PacketExtensionProvider() {
                @Override
                public PacketExtension parseExtension(XmlPullParser parser) throws Exception {
                    String json = parser.nextText();
                    return new GcmPacketExtension(json);
                }
            });
        }
        private final Deque<Channel> channels;
    
        public static SmackCcsClient instance() {
            if (instance == null) {
                synchronized (SmackCcsClient.class) {
                    if (instance == null) {
                        instance = new SmackCcsClient();
                    }
                }
            }
            return instance;
        }
    
        private SmackCcsClient() {
            channels = new ConcurrentLinkedDeque<Channel>();
            channels.addFirst(connect());
        }
    
        private class Channel {
            private XMPPConnection connection;
            /**
             * Indicates whether the connection is in draining state, which means that it will not accept any new downstream
             * messages.
             */
            private volatile boolean connectionDraining = false;
    
            /**
             * Sends a packet with contents provided.
             */
            private void send(String jsonRequest) throws NotConnectedException {
                Packet request = new GcmPacketExtension(jsonRequest).toPacket();
                connection.sendPacket(request);
            }
    
            private void handleControlMessage(Map<String, Object> jsonObject) {
                logger.debug("handleControlMessage(): {}", jsonObject);
                String controlType = (String) jsonObject.get("control_type");
                if ("CONNECTION_DRAINING".equals(controlType)) {
                    connectionDraining = true;
                } else {
                    logger.info("Unrecognized control type: {}. This could happen if new features are "
                            + "added to the CCS protocol.", controlType);
                }
            }
        }
    
        /**
         * Sends a downstream message to GCM.
         *
         */
        @Override
        public void sendDownstreamMessage(String message) throws Exception {
            Channel channel = channels.peekFirst();
            if (channel.connectionDraining) {
                synchronized (channels) {
                    channel = channels.peekFirst();
                    if (channel.connectionDraining) {
                        channels.addFirst(connect());
                        channel = channels.peekFirst();
                    }
                }
            }
            channel.send(message);
            logger.debug("Message Sent via CSS: ({})", message);
        }
    
        /**
         * Handles an upstream data message from a device application.
         *
         */
        protected void handleUpstreamMessage(Map<String, Object> jsonObject) {
            // PackageName of the application that sent this message.
            String category = (String) jsonObject.get("category");
            String from = (String) jsonObject.get("from");
            @SuppressWarnings("unchecked")
            Map<String, String> payload = (Map<String, String>) jsonObject.get("data");
            logger.info("Message received from device: category ({}), from ({}), payload: ({})", category, from,
                    JsonUtil.toJson(payload));
        }
    
        /**
         * Handles an ACK.
         *
         * <p>
         * Logs a INFO message, but subclasses could override it to properly handle ACKs.
         */
        public void handleAckReceipt(Map<String, Object> jsonObject) {
            String messageId = (String) jsonObject.get("message_id");
            String from = (String) jsonObject.get("from");
            logger.debug("handleAckReceipt() from: {}, messageId: {}", from, messageId);
        }
    
        /**
         * Handles a NACK.
         *
         * <p>
         * Logs a INFO message, but subclasses could override it to properly handle NACKs.
         */
        protected void handleNackReceipt(Map<String, Object> jsonObject) {
            String messageId = (String) jsonObject.get("message_id");
            String from = (String) jsonObject.get("from");
            logger.debug("handleNackReceipt() from: {}, messageId: ", from, messageId);
        }
    
        /**
         * Creates a JSON encoded ACK message for an upstream message received from an application.
         *
         * @param to
         *            RegistrationId of the device who sent the upstream message.
         * @param messageId
         *            messageId of the upstream message to be acknowledged to CCS.
         * @return JSON encoded ack.
         */
        protected static String createJsonAck(String to, String messageId) {
            Map<String, Object> message = new HashMap<String, Object>();
            message.put("message_type", "ack");
            message.put("to", to);
            message.put("message_id", messageId);
            return JsonUtil.toJson(message);
        }
    
        /**
         * Connects to GCM Cloud Connection Server using the supplied credentials.
         * 
         * @return
         */
        @Override
        public Channel connect() {
            try {
                Channel channel = new Channel();
                ConnectionConfiguration config = new ConnectionConfiguration(GCM_SERVER, GCM_PORT);
                config.setSecurityMode(SecurityMode.enabled);
                config.setReconnectionAllowed(true);
                config.setRosterLoadedAtLogin(false);
                config.setSendPresence(false);
                config.setSocketFactory(SSLSocketFactory.getDefault());
    
                channel.connection = new XMPPTCPConnection(config);
                channel.connection.connect();
    
                channel.connection.addConnectionListener(new LoggingConnectionListener());
    
                // Handle incoming packets
                channel.connection.addPacketListener(new PacketListener() {
                    @Override
                    public void processPacket(Packet packet) {
                        logger.debug("Received: ({})", packet.toXML());
                        Message incomingMessage = (Message) packet;
                        GcmPacketExtension gcmPacket = (GcmPacketExtension) incomingMessage.getExtension(GCM_NAMESPACE);
                        String json = gcmPacket.getJson();
                        try {
                            Map<String, Object> jsonObject = JacksonUtil.DEFAULT.mapper().readValue(json,
                                    new TypeReference<Map<String, Object>>() {});
                            // present for ack, nack and control, null otherwise
                            Object messageType = jsonObject.get("message_type");
                            if (messageType == null) {
                                // Normal upstream data message
                                handleUpstreamMessage(jsonObject);
                                // Send ACK to CCS
                                String messageId = (String) jsonObject.get("message_id");
                                String from = (String) jsonObject.get("from");
                                String ack = createJsonAck(from, messageId);
                                channel.send(ack);
                            } else if ("ack".equals(messageType.toString())) {
                                // Process Ack
                                handleAckReceipt(jsonObject);
                            } else if ("nack".equals(messageType.toString())) {
                                // Process Nack
                                handleNackReceipt(jsonObject);
                            } else if ("control".equals(messageType.toString())) {
                                // Process control message
                                channel.handleControlMessage(jsonObject);
                            } else {
                                logger.error("Unrecognized message type ({})", messageType.toString());
                            }
                        } catch (Exception e) {
                            logger.error("Failed to process packet ({})", packet.toXML(), e);
                        }
                    }
                }, new PacketTypeFilter(Message.class));
    
                // Log all outgoing packets
                channel.connection.addPacketInterceptor(new PacketInterceptor() {
                    @Override
                    public void interceptPacket(Packet packet) {
                        logger.debug("Sent: {}", packet.toXML());
                    }
                }, new PacketTypeFilter(Message.class));
    
                channel.connection.login(ExternalConfig.gcmSenderId() + "@gcm.googleapis.com", ExternalConfig.gcmApiKey());
                return channel;
            } catch (Exception e) {
                logger.error(Logging.FATAL, "Error in creating channel for GCM communication", e);
                throw new RuntimeException(e);
            }
        }
    
        /**
         * XMPP Packet Extension for GCM Cloud Connection Server.
         */
        private static final class GcmPacketExtension extends DefaultPacketExtension {
    
            private final String json;
    
            public GcmPacketExtension(String json) {
                super(GCM_ELEMENT_NAME, GCM_NAMESPACE);
                this.json = json;
            }
    
            public String getJson() {
                return json;
            }
    
            @Override
            public String toXML() {
                return String.format("<%s xmlns="%s">%s</%s>", GCM_ELEMENT_NAME, GCM_NAMESPACE,
                        StringUtils.escapeForXML(json), GCM_ELEMENT_NAME);
            }
    
            public Packet toPacket() {
                Message message = new Message();
                message.addExtension(this);
                return message;
            }
        }
    
        private static final class LoggingConnectionListener implements ConnectionListener {
    
            @Override
            public void connected(XMPPConnection xmppConnection) {
                logger.info("Connected.");
            }
    
            @Override
            public void authenticated(XMPPConnection xmppConnection) {
                logger.info("Authenticated.");
            }
    
            @Override
            public void reconnectionSuccessful() {
                logger.info("Reconnecting..");
            }
    
            @Override
            public void reconnectionFailed(Exception e) {
                logger.error("Reconnection failed.. ", e);
            }
    
            @Override
            public void reconnectingIn(int seconds) {
                logger.info("Reconnecting in {} secs", seconds);
            }
    
            @Override
            public void connectionClosedOnError(Exception e) {
                logger.info("Connection closed on error.");
            }
    
            @Override
            public void connectionClosed() {
                logger.info("Connection closed.");
            }
        }
    }
    

    我也是GCM的新手,面临同样的问题...我通过在CONNECTION_DRAINING消息上创建新的SmackCcsClient()来解决它。 较旧的连接应该仍然存在并接收消息,但不会发送,因为:

    protected volatile boolean connectionDraining = true;

    Google表示CCS将关闭连接:

    CCS将在准备就绪时处理启动连接。

    在CCS关闭连接之前,您将能够接收来自两个连接的消息,但只能以新消息发送消息。 当旧连接关闭时,它应该被销毁,我不知道是否垃圾收集器被调用或不...试图解决这个问题

    PS:我不能100%确定这个答案,但也许会为讨论开辟更多的空间。


    我只是将FCM Connection Draining的代码推送到我的FCM XMPP Server示例中。

    项目:用于FCM的XMPP连接服务器,使用最新版本的Smack库(4.2.2)+连接排水实施。

    GitHub链接:https://github.com/carlosCharz/fcmxmppserverv2

    YouTube链接:https://youtu.be/KVKEj6PeLTc

    如果您遇到问题,请查看我的疑难解答部分。 希望你能找到它有用。 问候!

    链接地址: http://www.djcxy.com/p/23487.html

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