Ditto Protocol messages of acknowledgements come in 2 different protocol topic variants.

Acknowledgement

An acknowledgment addressing a specific acknowledgement label contains that label as last part of the topic:

<namespace>/<thingName>/things/<channel>/acks/<ack-label>

The Ditto Protocol representation of an Acknowledgement is specified as follows:

Acknowledgements (aggregating)

An acknowledgment for aggregated structures contains several single acknowledgements as its payload, and the topic is without a label:

<namespace>/<thingName>/things/<channel>/acks

The Ditto Protocol representation of Acknowledgements is specified as follows:

Combined status code

The status code of the aggregating acknowledgements is derived based on the status codes of the contained single acks.

  • if only one acknowledgement is included, this acknowledgment’s status code is used
  • if several acknowledgements are included:
    • if all contained acknowledgements are successful (200>= HTTP status <=299), the overall status code is 200 (OK)
    • if at least one acknowledgement failed (HTTP status >299), the overall status code is 424 (Dependency failed)
Tags: protocol