There is no obvious way to set the trace ID for a message when the traceparent header is missing from the incoming message.

One use case example: for messages received from an external source (i.e. not controlled by the developer of the camel route), the incoming message body contains the trace ID.  It would be nice if there was a way to set the current trace ID with the one found in the message body.

There is a way to get into the current span via ActiveSpanManager.getSpan(exchange), but the API here doesn't allow you to override the ID.