getSubscriptionsStatus method
Gets the current status of a subscription by topic.
A batch subscription contains the status of each subscribed topic as returned by the broker only if the status is active.
A status of MqttSubscriptionStatus.doesNotExist is returned if a single subscription failed or all the subscriptions in a batch subscription fail.
For a batch subscription the topic is the topic of the first subscription in the batch.
Implementation
MqttSubscriptionStatus getSubscriptionsStatus(String topic) =>
subscriptionsManager!.getSubscriptionsStatus(topic);