Modifying the AMQP topic within the JavaScript mapping

[manucano8]

When specifying a target using AMQP 0.9.1, you have to set an address: "<exchange-name"/<"routing-key">.

I want to be able to overwrite this property in the JavaScript mapping, being able to route each message to a different AMQP queue depending on which property of a thing has been modified, or depending on the value taken by a specific property.

I think that this is possible in MQTT with mqtt.topic, a special header which overwrites the topic configured for the target, but I don't know if the same is possible with AMQP. If not, it would be good to implement it.

[thjaeckle]

Sure, that makes sense for all other connection types as well 👍

Good issue for a simple contribution to Ditto