The `Request::Trigger` message is clumsy
It has a type field (common.event_type) and based on its value, one of the push or patch fields should be used. This screams for an enum solution.
However, note that changing this is going to break all existing adapter implementations. That is OK, but the transition needs to be managed.
In addition to being clumsy, the request message could contain the broker run id, in case the adapter wants to include it in its run log