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dotnet
CleanSession==false not working
I use ManagedClient (Windows .net core) with Mosquitto as server. When I first connect I set CleanSession to false. After this I subscribe to several topics and receive Messages. After a call to StopAsync the message flow stops (intended). When I call StartAsync again (passing the same parameters including CleanSession==false) I am connected and can send messages. But I don't receive any in ApplicationMessageReceived handler.
I thought CleanSession==false kepps subscriptions alive (restortes them). Am I doing something wrong or is this an intended behaviour?
From https://www.hivemq.com/blog/mqtt-essentials-part-7-persistent-session-queuing-messages/:
When the clean session flag is set to false, the broker creates a persistent session for the client. All information and messages are preserved until the next time that the client requests a clean session. If the clean session flag is set to false and the broker already has a session available for the client, it uses the existing session and delivers previously queued messages to the client.
As far as I understand it, this is a bug. @chkr1011 Any ideas here?
@chkr1011 any news on this? Or exist there any extension points to hook in to make this scenario reliable?
The managed client currently does not support existing sessions. The reason is that this would also require a handling for exisitng subscriptions. This includes separating them into different lists in order to determine whether a subscription is "new" (added while being disconnected) or already present at the server.
I you need this feature I recommend to use the regular client from the core library. There you need to implement retries, reconnects on your own but you can also decide how to deal with such situations as a described above.
Since https://github.com/dotnet/MQTTnet/issues/492 and https://github.com/dotnet/MQTTnet/pull/836 seem to be done, this should be possible now, I guess?
