onConnect callback required for renewing subscriptions

[elementzonline]

onConnect callback feature is required when the client gets disconnected when there is network loss. This callback can be used to renew subscriptions.

[shamblett]

Yes OK I'll update the client to add one.

As a thought, the client maintains a list of subscriptions, would an option to automatically re-subscribe to these on re-connection be useful?

[drost]

On that note, how is reconnection supposed to work? If there is an error during the initial connect, I can't see that a reconnection attempt will be made.

[shamblett]

The client automatically tries to reconnect if the initial connection attempt fails, at the moment this is hard wired to 3 attempts in total, you can see this if you edit the mqtt_client.dart in the examples folder to connect to a non-existent broker and turn logging on

[elementzonline]

I solved this issue for now by using a 5 second one shot timer to call _connect when the timer expires in the _onDisconnect

void _onDisconnected() {
client.disconnect();
Timer(Duration(seconds: 5), _reconnect);
}

void _reconnect() {
print('MQTT client reconnecting');
_connect();
}

[shamblett]

OnConnect callback added, client re-published at 5.0.0.