unsubscribeSubscription method
Unsubscribe from a subscription.
Implementation
void unsubscribeSubscription(MqttSubscription? subscription) {
if (subscription == null) {
throw ArgumentError(
'MqttSubscriptionManager::unsubscribeSubscription - subscription is null');
}
final unsubscribeMsg = MqttUnsubscribeMessage()
.withMessageIdentifier(messageIdentifierDispenser.nextMessageIdentifier)
.fromTopic(subscription.topic)
.withUserProperties(subscription.userProperties);
_connectionHandler.sendMessage(unsubscribeMsg);
pendingUnsubscriptions[unsubscribeMsg.variableHeader.messageIdentifier] =
<MqttSubscription>[subscription];
}