I'm currently in the process of migrating my Django application monitoring from beeline to OpenTelemetry. One feature of beeline was the add_rollup_field function which can specify a field to be summed in a trace's root span. For example, if we add a db.total_duration rollup field, we can use that to sum all of the db.duration values for a root span.
What would be the best way to implement this in OpenTelemetry? Is there a good way to pass these values to parent spans and eventually to the root span? I've looked into Baggage but that appears to mainly be used to update a context for passing down the call stack, not up.