[DAS2] Dasypus status

[Andrew Dalke]

Me:
>>    - we were going to change the <PROP> section of the
>> spec, right?  What were the changes?

Lincoln:
> I don't know!  What *were* the changes?

Here's the current spec

   <PROP> (zero or more)
   A property of this feature. Properties are typed using the
   ptype attribute. The value of the property may indicated by
   a URL given by the href attribute, or may be given inline
   as the CDATA content of the <PROP> section.

   ptype – a URL describing the property type
   href (optional) – a URL that provides more information
    about the property of this feature, can be used for
    database XREFs
   mime_type (optional) – MIME type of the CDATA contents
   content_encoding (optional) – Encoding of the CDATA contents
   CDATA text – Content

The proposal was to get rid of the CDATA text.  That makes
things less complex, at the cost of a potential extra
network lookup.  We can get rid of the mime_type and
content_encoding fields too.

We don't need to have the extra lookup.  A couple days
ago I was reminded of the "data" URL scheme
     http://www.ietf.org/rfc/rfc2397.txt

That RFC gives a couple of examples:

   data:,A%20brief%20note

is the text/plain string "A brief note"


    <IMG
    SRC="data:image/gif;base64,R0lGODdhMAAwAPAAAAAAAP///ywAAAAAMAAw
    AAAC8IyPqcvt3wCcDkiLc7C0qwyGHhSWpjQu5yqmCYsapyuvUUlvONmOZtfzgFz
    ByTB10QgxOR0TqBQejhRNzOfkVJ+5YiUqrXF5Y5lKh/DeuNcP5yLWGsEbtLiOSp
    a/TPg7JpJHxyendzWTBfX0cxOnKPjgBzi4diinWGdkF8kjdfnycQZXZeYGejmJl
    ZeGl9i2icVqaNVailT6F5iJ90m6mvuTS4OK05M0vDk0Q4XUtwvKOzrcd3iq9uis
    F81M1OIcR7lEewwcLp7tuNNkM3uNna3F2JQFo97Vriy/Xl4/f1cf5VWzXyym7PH
    hhx4dbgYKAAA7"
    ALT="Larry">

is an inline image of some bearded dude, in b&w.

More info about the data URI scheme (dated)
   http://www.mozilla.org/quality/networking/docs/aboutdata.html
with on-line examples at
   http://www.mozilla.org/quality/networking/testing/datatests.html

Cool!  Safari understands it!  Actually, it seems that
everyone except IE understand it these days.

Anyway, using a data URL scheme lets us get rid of the
CDATA, content_encoding and mime_type fields of the <PROP>
and still let us embed small chunks of data in-line.

					Andrew
					dalke at dalkescientific.com