I will be looking at you MQTT implmentation with interest as I use MQTT regularly. However there is no way,IMHO, "Blobs" of any size will (or should IMHO) use MQTT. Trying to send Blob's does one of two things

a. Stops (OK to a trickle) all other MQTT traffic as you have to set buffers so large to get the Blob transfer within a reasonable time.

b. Using smaller buffers ,i found , just means very very long download times (Note my testing was with RPI acting as a Broker and using Python clent on Windows as receiver, RPI as a client as the Publisher ).

The above does depend on file sizes and small JPG would be fine!

Most other devices,i have have used, work pretty well except for a few devices (but really thats down to driver protocol problems - e.g. Moonlite focuser protocol and the temp reading times out too quickly!)

An alternative maybe,would be to just send the file name(and associated IP address or DNS name) of the Blob and/or initiate another protocol to broadcast/stream the file.

For Internet or distributed Indi I think MQTT has a few advantages IMO - all local working(one SCB) not really IMO.

Nice One

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