[XML-SIG] XBEL DTD validation question

[Fred L. Drake, Jr.]

On Tuesday 24 May 2005 15:16, Carol Le wrote:
 > I apologize if this is not the right place to direct my question, but
 > I have not been able to find any forums with support for XBEL.  If
 > this is not the write place to direct these questions, please let me
 > know where I can get some help.  :c)

This is as good a place as any.

 > I am working on a master's thesis that argues for a standard to be
 > established for internet bookmarks.  My thesis investigates XBEL as a

I'd be interested in seeing the result, or a summary, when your thesis is 
complete.

 > One error that I continually get throughout my XML document is
 > something like the following:
 > -- Attribute value "09BDE5A6-6CE7-4137-AD4D-5FC6D380BFD5" of type ID
 > must be a name
 > This happens for every <bookmark id="someID"> tag that I use where
 > someID does not start with a letter.  Does XBEL only allow name
 > ID's?  Safari uses these id's that can oftentimes start with a
 > number.  Does this mean that for XBEL, you cannot use Safari's ID's?

XBEL uses XML IDs.  It sounds like Safari is using something else as an 
identifier; not unreasonable.  Encoding these into XBEL requires using some 
other metadata structure.

 > The second error that I get is something like the following:
 > -- Attribute "file-version" must be declared for element type
 > "metadata".
 > This occurs for every single <metadata> element I have.  For the
 > above error, for example, the metadata element was <metadata
 > owner="Safari" file-version="1"/>.  From reading the DTD and looking
 > at some XBEL examples, I was under the understanding that the
 > metadata attribute was so that you could put any application-specific
 > items.  However, all of my application-specific items are not
 > validating correctly.  Any suggestions?

To validate, you'll need to create a new DTD that adds the additional 
structures you need.  DTD validation can't specify that unknown attributes 
are allowed; this is a general limitation of DTDs.  It should be fairly easy 
to create a derived DTD that supports the additional structures you need.  
Alternatively, you could create another kind of schema (W3C XSD, RelaxNG) for 
ues in validating specific documents.


  -Fred

-- 
Fred L. Drake, Jr.   <fdrake at acm.org>