RDFLib will accept broken RDF/XML

[gromgull]

This RDF/XML is invalid and should raise an exception:

import rdflib

data='''<?xml version="1.0" encoding="utf-8"?>
<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
    xmlns:http="http://www.w3.org/2011/http#">

    <http:HeaderElement rdf:about="#he0">
        <http:params>
            <http:Parameter rdf:about="#param0_0" />
            <http:Parameter rdf:about="#param0_1" />
        </http:params>
    </http:HeaderElement>

</rdf:RDF>
'''

g = rdflib.Graph().parse(data=data)

print g.serialize(format='n3')

[gromgull]

Not so fast :)

[joernhees]

This currently breaks master... the test fails here:

   <rdf:Description about="http://meetings.example.com/cal#m1">
        <Location parseType="Resource">
            <zip xmlns="http://www.another.example.org/geographical#">02139</zip>
            <lat xmlns="http://www.another.example.org/geographical#">14.124425</lat>
            <long xmlns="http://www.another.example.org/geographical#">14.245</long>
        </Location>
        <chair resource="http://www.example.org/people#fred"/>
        <homePage resource="http://meetings.example.com/m1/hp"/>
    </rdf:Description>

who doesn't love rdf+xml: http://www.w3.org/TR/2014/REC-rdf-syntax-grammar-20140225/#section-Syntax-parsetype-resource

[gromgull]

Oh dear - It's not just that my hacky attempt at raising an exception wasn't working, but our parseType=Resource parsing is completely broken.

If I reduce down the example to this:

<?xml version="1.0" encoding="utf-8"?>
<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
    xmlns="http://www.example.org/meeting_organization#">

    <rdf:Description about="http://meetings.example.com/cal#m1">
        <Location parseType="Resource">
            <zip xmlns="http://www.another.example.org/geographical#">02139</zip>
            <lat xmlns="http://www.another.example.org/geographical#">14.124425</lat>
        </Location>
    </rdf:Description>
</rdf:RDF>

And parse it without my exception raising code, I get:

@prefix : <http://www.example.org/meeting_organization#> .
@prefix default1: <http://www.another.example.org/geographical#> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@prefix xml: <http://www.w3.org/XML/1998/namespace> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .

[] <parseType> "Resource" .

[] a default1:zip .

[] <about> "http://meetings.example.com/cal#m1" ;
    :Location [ a default1:lat ] .

which is complete gobblygook. AFAIK the rdf/xml code hasn't been touched for a long time, and it may have been broken forever. I'll investigate.

[gromgull]

So at first I started going back in rdflib history, and this was broken all the way back to version 2.0.6 - the earliest tagged version we have :)

BUT, as I start looking into the rdfxml parser, I realise that it's not the parsed that is broken, it's the example. The parseType here needs to be in the rdf namespace:

<?xml version="1.0" encoding="utf-8"?>
<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
    xmlns="http://www.example.org/meeting_organization#">

    <rdf:Description about="http://meetings.example.com/cal#m1">
        <Location rdf:parseType="Resource">
            <zip xmlns="http://www.another.example.org/geographical#">02139</zip>
            <lat xmlns="http://www.another.example.org/geographical#">14.124425</lat>
        </Location>
    </rdf:Description>
</rdf:RDF>

That XML parses fine, and no exception is raised.

:)

[joernhees]

phew ;)

the thing is: build still breaks.

[joernhees]

ah, i think you just forgot to restore https://github.com/RDFLib/rdflib/edit/master/test/test_issue363.py to something which works...

should we report upstream that http://www.w3.org/2000/10/swap/test/meet/white.rdf is broken?