Validation irrespective of DOCTYPE?

[Jeff Turner <jeff@socialchange.net.au>]

Hi,

I'm getting XML from a socket, which may or may not contain a DOCTYPE
declaration, which would indicate the associated DTD. Either way, I'd
like to validate this XML. Two approaches I can think of:

 - build a non-validated DOM, add the DOCTYPE decl to the DOM,
   revalidate the DOM. Hampered by lack of revalidating parsers.
 - Manually parse the XML and add the DOCTYPE to the text stream, and
   then do a validating parse.

Or can I just insist that my upstream source supplies a DOCTYPE? Is this
commonly regarded as part of the XML "contract"?

thanks,

--Jeff