@Override
public void onReconnected() {
log.info("reconnected");
if (mode.contains(MODE.RESEND_SUBSCRIBE_ON_RECONNECTED)) {
Set<String> channels;
// channel as sourceDispatcherId
channels = new HashSet<String>();
channels.add(getSourceDispatcherId());
driverImpl.subscribeChannels(channels);
// channels as object_IDs registered with localObjectsMap
channels = localObjectsMap.keySet();
if (!channels.isEmpty()) {
driverImpl.subscribeChannels(channels);
}
// all channels registered with subscribersMap
channels = subscribersMap.getSubscribedChannels();
if (!channels.isEmpty()) {
driverImpl.subscribeChannels(channels);
}
// re-SUBSCRIBE completed with all the registered channels.
pubSubDriverSuspended = false; // Resumed
} else {
// You may add some code here to inform other objects that
// the network connectivity has resumed or the pubsub server
// has become available.
}
}
/**
* Closes the services.
*
* <p>You can also do "try-with-resources" to automatically close this class.
*/
public void close() {
// TODO: Graceful termination of all the components and the transport
// TODO: subscriptionFeeder termination
driverImpl.close();
remoteTransactions.onFinalize();
subscribersMap.clear();
log.info("terminated");
}
/**
* Channel unsubscription service.
*
* @param subscriberId subscriber's object ID
* @param channelsToBeUnsubscribed channels to be unsubscribed
*/
public void unsubscribeChannels(
final String subscriberId, final Map<String, Set<String>> channelsToBeUnsubscribed) {
Set<String> channels = new HashSet<>();
for (String publisherId : channelsToBeUnsubscribed.keySet()) {
Set<String> eventIds = channelsToBeUnsubscribed.get(publisherId);
for (String eventId : eventIds) {
String channel = channelString(publisherId, eventId);
if (subscribersMap.removeSubscription(channel, subscriberId)) {
channels.add(channel);
}
}
}
if (!channels.isEmpty() && !pubSubDriverSuspended) {
driverImpl.unsubscribeChannels(channels);
}
}
/**
* onMessage implementation.
*
* <p>This method has two roles:
*
* <ul>
* <li>Works like a mail transfer agent to transfer a received request or event to {@link
* org.o3project.odenos.remoteobject.RemoteObject}.
* <li>Supports both synchronous and asynchronous messaging.
* </ul>
*/
@Override
public void onMessage(final String channel, byte[] message) {
serial++; // Serial number for incoming messages.
try {
BufferUnpacker upk = msgpack.createBufferUnpacker(message);
// read delivery header.
byte type = upk.readByte();
final int sno = upk.readInt(); // Sequence number for outgoing request messages.
final String sourceObjectId = upk.readString(); // i.e., channel
RemoteObject localObject = null;
Queue<Mail> mailbox = null;
Mail mail = null;
switch (type) {
case TYPE_REQUEST: // Transaction(request): synchronous operation
/*
* --- request --> dispatchRequest() -------> [RemoteObject]
* |
* <-- response --- publishResponseAsync() <-------+
*/
final Request request = upk.read(Request.class);
if (log.isDebugEnabled()) {
log.debug(
"Request received:\n"
+ " MessageDispatcher: {}\n"
+ " sno: {}\n"
+ " channel: {}\n"
+ " method: {}\n"
+ " objectId: {}\n"
+ " sourceObjectId: {}\n"
+ " path: /{}/\n"
+ " body: {}",
sourceDispatcherId,
sno,
channel,
request.method,
request.objectId,
sourceObjectId,
request.path,
request.getBodyValue());
}
// Wraps the request with Mail and deliver it to a mailbox.
String to = request.objectId;
mail = new Mail(serial, sno, to, sourceObjectId, this, request, null);
localObject = localObjectsMap.get(to);
if (localObject != null) {
mailbox = localObject.getMailbox();
synchronized (mailbox) {
mailbox.add(mail);
if (!localObject.isRunning()) {
localObject.setRunning(true);
// Assigns a thread to read a mail in the mailbox.
actor.read(localObject);
}
}
}
break;
case TYPE_RESPONSE: // Transaction(response): synchronous operation
/*
* publishRequestAsync()
* requestSync() -> [RemoteTransaction] ---- request -----> [RemoteObject]
* <-- ^ |
* | publishResponseAsync()
* | |
* +- signalResponse() <-- response --+
*/
Response response = upk.read(Response.class);
if (log.isDebugEnabled()) {
log.debug(
"Response received:\n"
+ " MessageDispatcher: {}\n"
+ " channel: {}\n"
+ " statusCode: {}\n"
+ " body: {}",
sourceDispatcherId,
channel,
response.statusCode,
response.getBodyValue());
}
remoteTransactions.signalResponse(sno, response);
break;
case TYPE_EVENT: // Asynchronous
/*
* publishEventAsync() -- event --> dispatchEvent() --> [RemoteObject]
* :
* [EventSubscriptionMap]
*/
final Event event = upk.read(Event.class);
if (log.isDebugEnabled()) {
log.debug(
"Event received:\n"
+ " MessageDispatcher: {}\n"
+ " channel: {}\n"
+ " body: {}",
sourceDispatcherId,
channel,
event.getBodyValue());
}
// All the subscribers of the channel
final Collection<String> subscribers = subscribersMap.getSubscribers(channel);
if (subscribers == null) { // No subscribers found on the channel
if (log.isDebugEnabled()) {
log.debug("no subscribers subscribing the channel: {}", channel);
}
return; // Silently discards the event
}
// Wraps the event with Mail and deliver it to a mailbox.
for (String subscriber : subscribers) {
localObject = localObjectsMap.get(subscriber);
if (localObject != null) {
mail = new Mail(serial, sno, subscriber, channel, this, null, event);
mailbox = localObject.getMailbox();
synchronized (mailbox) {
mailbox.add(mail);
if (!localObject.isRunning()) {
localObject.setRunning(true);
// Assigns a thread to read a mail in the mailbox.
actor.read(localObject);
}
}
}
}
break;
default:
break;
}
} catch (Exception e) {
log.error("onMessage failed", e);
}
}
