ietf-xml-mime
[Top] [All Lists]

Re: Registration of media type application/xhtml-voice+xml

2005-07-13 23:51:16

At 01:33 05/07/14, Gerald McCobb wrote:

I asked the IESG to postpone the publication of the application/xhtml-voice+xml media type as an informational RFC. The registration is not correct. It should be application/xhtml+voice+xml. The application/xhtml+voice+xml media type was the original submission.

There is an issue with the original submission:

One of the reviewers pointed out that "a certain class of error could be avoided by renaming this application/xhtml-plus-voice+xml... I don't know of any other "+xml" [see RFC3023] media types that have a "+" in the name... a poorly-constructed regexp looking for +xml along the lines of /\+(.*)$/ would miss this one."

I agree with that reviewer that the type should not contain
'+' characters except before 'xml'. All other subtypes have used '-'
as a separator. The '+' separator was specifically introduced to
express the fact that the '+xml' part is something more than
a simple subtype.

Although there is probably nothing in RFC 3023 explicitly
disallowing the use of '+' for "arbitrary use", I think that
the whole rationale for '+xml' in Appendix A of RFC 3023
(in particular http://www.ietf.org/rfc/rfc3023.txt, A.12)
seem to indicate that it shouldn't be done.



I believe this argument is not strong enough to prevent approval of the application/xhtml+voice+xml media type:

2. The argument for having "+" in the subtype is unconvincing, given that the simplest method to determine if something is XML is also the safest, that is, if the last four characters are "+xml" or "/xml" then the document is XML, otherwise it is not. If that has to be done with regexps, instead of just examining the last four bytes, that would be /[/+]xml$/. If type and subtype were split already it would be /\+?xml$/ for the subtype.

I think the regexp example is only the tip of the iceberg. Not using
the plus will allow better future extensibility.


Regards, Martin.