New error type should be a PrepareError variant, not a URI

[divergentdave]

The way that section 2 is written suggests that it defines a new error type URI, urn:ietf:params:ppm:dap:error:unauthenticatedReport. However, the error is only ever produced during aggregation job processing, within the scope of a single report. Thus, what is really needed is a new PrepareError variant. DAP does not yet define a registry for extensibility of this enum, see ietf-wg-ppm/draft-ietf-ppm-dap#487.

[cpriebe]

Thanks! That makes sense to me. I was following the wording in https://datatracker.ietf.org/doc/draft-wang-ppm-dap-taskprov for which we might need the same?

Will add a TODO to the doc for now.

[cpriebe]

Note added but will leave this open to track the actual resolution.

[divergentdave]

I think taskprov is using error type URIs is alright, since its error can arise during report uploading. Only errors during report share preparation have to be represented using this more limited TLS-style enum.

[cpriebe]

Ah, right. That makes sense.