Re: [xml] issue with libxml2, python and entities

[Daniel Veillard <veillard redhat com>]

On Sat, Jan 27, 2007 at 12:34:21AM +0000, Mike Kneller wrote:
> I am not sure if I have located a bug or not....
> 
> Using Python (2.4) and libxml2.2.6.22
> 
> When I load an document containing an entity, if I attempt to read  
> the value of a node containing an entity, I get the text content and  
> the entity disappears.
> In the following example, when looking at root.content I would expect  
> to see '©2007', instead all I get is '2007'.
> 
> I was advised on the #XML IRC channel to construct a simple test  
> case, so here it is:
> 

  On IRC you said the entity was defined in the internal subset, it's not

> File 1: test.xml
> 
> <?xml version="1.0"?>
> <!DOCTYPE content [
> <!ENTITY % HTMLlat1 PUBLIC
>     "-//W3C//ENTITIES Latin 1 for XHTML//EN"
>     "http://www.w3.org/TR/xhtml1/DTD/xhtml-lat1.ent";>
> %HTMLlat1;
> ]>
> <content>
> 	<p>&copy;2007</p>
> </content>

  libxml2 doesn't load externl subset by default,

> File 2: testcase.py
> 
> import libxml2
> sourcedoc = libxml2.parseFile( 'test.xml' )
> root = sourcedoc.getRootElement()
> print root.serialize()
> print root.content

  So your content element has 2 children an entity reference
to copy whose content is unknown and the text node with "2007"
> 
> Reading the source for libxml2.py, I find the following:
>      def getContent(self):
>          """Read the value of a node, this can be either the text
>             carried directly by this node if it's a TEXT node or the
>             aggregate string of the values carried by this node
>             child's (TEXT and ENTITY_REF). Entity references are
>             substituted. """
>          ret = libxml2mod.xmlNodeGetContent(self._o)
>          return ret
> 
> 
> Which in my (admittedly limited) understanding I would have thought  
> would return the translated entity as well as the text when I examine  
> root.content.
> 
> Is this a bug, or am I doing something wrong?

  Not askling to load the external subset, use readFile and pass the
XML_PARSE_DTDLOAD option. It should work even with the ancient version
2.6.22 , but please firtst upgrade first in case of problem.

Daniel

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