Handle incorrect revision numbers more cleanly

[bifurcation]

The submission workflow has the author submit a tag in the form of draft-documentname-revision, which gets used as the file name in submission. If the author submits a tag with the incorrect version (say -03 when the most recent published is -01), then the datatracker will return a 400 error on submission and the CI job will fail with no message other than the 400.

It seems like the submission script could check that the tag has the correct form and revision for the document in question, and if not, fail with a helpful error. It would also be helpful to provide a more intelligible error in response to datatracker errors. ("The datatracker didn't like your submission. Have you checked...?")

[martinthomson]

I just tried this myself and got this:

{"error": "Validation Error", "messages": ["Invalid revision (revision 02 is expected)"]}+ echo

Admittedly, this is buried in a bunch of diagnostic messages, but this is a hugely error-prone sequence that runs rarely, so suppressing those might be unwise.

That said, I think we can probably avoid doing an upload if the tag is not the next in sequence or a new name with -00. Then, as you say, the error message can be a lot clearer.