I have 5 products in operation with a web app that subscribes to the event streams from each product’s devices and logs or acts on those events. Recently I have noticed that there are duplicate events being received. Sometimes these are duplicates (2 the same) and some times triplicates (3 the same) and very occasionally quadruplicates (4 the same). I know that they are the same because the message contain a date/time stamp in the data body when they were created. The duplicates are across all products and are random.
In the past I have seen duplicates where the web app subscribed to both a user account and the product account - every event was duplicated. This issue was addressed a while back once all devices were moved to be products.
There is a possibility that the device is resending the event message [each device has a store and send mechanism which only deletes the messages when there is a confirmed publish].
Just wondering if anyone else has seen duplicated messages at their web apps?