Method addBeforeRemoveSubscription

src/backend/datasources/MQTTClient.cpp:459–509

! * \brief Adds a MQTTSubscription to the MQTTClient *Used when the user unsubscribes from a topic of a MQTTSubscription * * \param topic, the name of the topic * \param QoS */

 * \param QoS
 */
void MQTTClient::addBeforeRemoveSubscription(const QString& topicName, quint8 QoS) {
	// We can't add the subscription if it already exists
	if (!m_subscriptions.contains(topicName)) {
		// Subscribe to the topic
		const QMqttTopicFilter filter{topicName};
		auto* temp = m_client->subscribe(filter, QoS);
		if (temp) {
			// Add the MQTTSubscription and other connected data
			// qDebug()<<"Add subscription before remove: " << temp->topic() << "  " << temp->qos();
			m_subscriptions.push_back(temp->topic().filter());
			m_subscribedTopicNameQoS[temp->topic().filter()] = temp->qos();

			auto* newSubscription = new MQTTSubscription(temp->topic().filter());
			newSubscription->setMQTTClient(this);

			addChildFast(newSubscription);
			m_MQTTSubscriptions.push_back(newSubscription);

			// Search for the subscription the topic belonged to
			bool found = false;
			MQTTSubscription* superiorSubscription = nullptr;
			for (auto* subscription : m_MQTTSubscriptions) {
				if (checkTopicContains(subscription->subscriptionName(), topicName) && topicName != subscription->subscriptionName()) {
					found = true;
					superiorSubscription = subscription;
					break;
				}
			}

			if (found) {
				// Search for topics belonging to the superior(old) subscription
				// which are also contained by the new subscription
				QVector<MQTTTopic*> topics = superiorSubscription->topics();
				// 				qDebug()<< topics.size();

				QVector<MQTTTopic*> inferiorTopics;
				for (auto* topic : topics) {
					if (checkTopicContains(topicName, topic->topicName())) {
						inferiorTopics.push_back(topic);
					}
				}

				// Reparent these topics, in order to avoid data loss
				for (auto* inferiorTopic : inferiorTopics) {
					inferiorTopic->reparent(newSubscription);
				}
			}
			connect(temp, &QMqttSubscription::messageReceived, this, &MQTTClient::MQTTSubscriptionMessageReceived);
		}
	}
}

/*!
 * \brief Reparents the given MQTTTopic to the given MQTTSubscription