Jetstream and Redirection using NATS

[rhodee]

I learned about subject mapping and wondered if it was possible to configure NATS to perform redirection. I was not able to find docs or issues. My challenge is I have a CDC envelope which looks like this:

type Event struct {
    ID     string    `json:"id"`
    Schema string    `json:"schema"`
    Table  string    `json:"table"`
    Action string    `json:"action"`
    Data   EventData `json:"data"`
}

Within Data the payload field contains a CloudEvent (validated for consistency before CDC emission). What approaches can be used to read and concatenate the aggregatetype and aggregateid fields and then use the resulting value as the subject to redirect to?

Is it possible to create a configuration like the following?

{
  "name": "allevents",
  "subjects": [ "allevents.*"],
  "retention": "limits",
  ...
  "republish": [
    {
      "src": "allevents",
      "dest": "{{$msg.data.aggregatetype.aggregateid}}"
    }
  ]

I came across Nex, and it seems more advanced than what I think my needs are.