private Set<String> getMatchingSubscriptions(String partition, String topic) {
Set<String> topicFilterKeys = new HashSet<>();
ListIterator<String> pathIterator =
Arrays.asList(topic.split(Constant.PATH_SEPARATOR)).listIterator();
List<String> growingTitles = new ArrayList<>();
while (pathIterator.hasNext()) {
String name = pathIterator.next();
List<String> slWildCardList = new ArrayList<>(growingTitles);
if (pathIterator.hasNext()) {
// We deal with wildcard.
slWildCardList.add(Constant.SINGLE_LEVEL_WILDCARD);
topicFilterKeys.add(quickCheckIdKey(partition, slWildCardList));
} else {
// we deal with full topic
slWildCardList.add(name);
}
List<String> reverseSlWildCardList = new ArrayList<>(slWildCardList);
growingTitles.add(name);
int sizeOfTopic = slWildCardList.size();
if (sizeOfTopic > 1) {
sizeOfTopic -= 1;
for (int i = 0; i < sizeOfTopic; i++) {
if (i >= 0) {
slWildCardList.set(i, Constant.MULTI_LEVEL_WILDCARD);
reverseSlWildCardList.set(sizeOfTopic - i, Constant.MULTI_LEVEL_WILDCARD);
topicFilterKeys.add(quickCheckIdKey(partition, slWildCardList));
topicFilterKeys.add(quickCheckIdKey(partition, reverseSlWildCardList));
}
}
}
}
topicFilterKeys.add(quickCheckIdKey(partition, growingTitles));
return topicFilterKeys;
}
/**
* Provides the Observer with a new item to observe.
*
* <p>The {@link com.caricah.iotracah.core.modules.Server} may call this method 0 or more times.
*
* <p>The {@code Observable} will not call this method again after it calls either {@link
* #onCompleted} or {@link #onError}.
*
* @param iotMessage the item emitted by the Observable
*/
@Override
public void onNext(IOTMessage iotMessage) {
getExecutorService()
.submit(
() -> {
log.info(" onNext : received {}", iotMessage);
try {
IOTMessage response = null;
switch (iotMessage.getMessageType()) {
case ConnectMessage.MESSAGE_TYPE:
ConnectMessage connectMessage = (ConnectMessage) iotMessage;
response =
ConnectAcknowledgeMessage.from(
connectMessage.isDup(),
connectMessage.getQos(),
connectMessage.isRetain(),
connectMessage.getKeepAliveTime(),
MqttConnectReturnCode.CONNECTION_ACCEPTED);
break;
case SubscribeMessage.MESSAGE_TYPE:
SubscribeMessage subscribeMessage = (SubscribeMessage) iotMessage;
List<Integer> grantedQos = new ArrayList<>();
subscribeMessage
.getTopicFilterList()
.forEach(
topic -> {
String topicKey =
quickCheckIdKey(
"",
Arrays.asList(topic.getKey().split(Constant.PATH_SEPARATOR)));
Set<String> channelIds = subscriptions.get(topicKey);
if (Objects.isNull(channelIds)) {
channelIds = new HashSet<>();
}
channelIds.add(subscribeMessage.getConnectionId());
subscriptions.put(topicKey, channelIds);
grantedQos.add(topic.getValue());
});
response =
SubscribeAcknowledgeMessage.from(
subscribeMessage.getMessageId(), grantedQos);
break;
case UnSubscribeMessage.MESSAGE_TYPE:
UnSubscribeMessage unSubscribeMessage = (UnSubscribeMessage) iotMessage;
response =
UnSubscribeAcknowledgeMessage.from(unSubscribeMessage.getMessageId());
break;
case Ping.MESSAGE_TYPE:
response = iotMessage;
break;
case PublishMessage.MESSAGE_TYPE:
PublishMessage publishMessage = (PublishMessage) iotMessage;
Set<String> matchingTopics =
getMatchingSubscriptions("", publishMessage.getTopic());
for (String match : matchingTopics) {
Set<String> channelIds = subscriptions.get(match);
if (Objects.nonNull(channelIds)) {
channelIds.forEach(
id -> {
PublishMessage clonePublishMessage = publishMessage.cloneMessage();
clonePublishMessage.copyTransmissionData(iotMessage);
clonePublishMessage.setConnectionId(id);
pushToServer(clonePublishMessage);
});
}
}
if (MqttQoS.AT_MOST_ONCE.value() == publishMessage.getQos()) {
break;
} else if (MqttQoS.AT_LEAST_ONCE.value() == publishMessage.getQos()) {
response = AcknowledgeMessage.from(publishMessage.getMessageId());
break;
}
case PublishReceivedMessage.MESSAGE_TYPE:
case ReleaseMessage.MESSAGE_TYPE:
case CompleteMessage.MESSAGE_TYPE:
case DisconnectMessage.MESSAGE_TYPE:
case AcknowledgeMessage.MESSAGE_TYPE:
default:
DisconnectMessage disconnectMessage = DisconnectMessage.from(true);
disconnectMessage.copyTransmissionData(iotMessage);
throw new ShutdownException(disconnectMessage);
}
if (Objects.nonNull(response)) {
response.copyTransmissionData(iotMessage);
pushToServer(response);
}
} catch (ShutdownException e) {
IOTMessage response = e.getResponse();
if (Objects.nonNull(response)) {
pushToServer(response);
}
} catch (Exception e) {
log.error(" onNext : Serious error that requires attention ", e);
}
});
}