- From: Seaborne, Andy <andy.seaborne@hp.com>
- Date: Sat, 17 May 2008 20:24:36 +0000
- To: Manu Sporny <msporny@digitalbazaar.com>, RDFa mailing list <public-rdf-in-xhtml-tf@w3.org>, Benjamin Nowack <bnowack@semsol.com>
- CC: Dave Beckett <dave@dajobe.org>
> -----Original Message----- > From: Manu Sporny [mailto:msporny@digitalbazaar.com] > Sent: 17 May 2008 19:53 > To: RDFa mailing list; Seaborne, Andy; Benjamin Nowack > Cc: Dave Beckett > Subject: 2 RDFa SPARQL Test Harness Issues > > Hi all, > > This is a summary of all the current RDFa Test Harness issues that we > have including a couple I found this morning. I'm cc'ing Andy and Benji > in the hope that they have some insight into these issues. All test > cases can be viewed via Crazy Ivan (RDFa Test Harness): > > http://rdfa.digitalbazaar.com/rdfa-test-harness/ > > UTF-8 issues with ARC and SPARQL.org - TCs 60, and 108 > ------------------------------------------------------ > > We currently have two test cases that use UTF-8 characters (TC#60 and > TC#108). The SPARQL.org and ARC SPARQL engines both die processing > queries containing multi-byte UTF-8 characters: > > Here's what SPARQL.org does: > http://sparql.org/sparql?query=%EF%BB%BFASK+WHERE+%7B%0D%0A%09%3Chttp%3A%2F%2 > Fwww.example.org%2F%23matsumoto- > kimiko%3E+%3Chttp%3A%2F%2Fwww.w3.org%2F1999%2F02%2F22-rdf-syntax- > ns%23type%3E+%3Chttp%3A%2F%2Fxmlns.com%2Ffoaf%2F0.1%2FPerson%3E+.%0D%0A%09%3C > http%3A%2F%2Fwww.example.org%2F%23matsumoto- > kimiko%3E+%3Chttp%3A%2F%2Fxmlns.com%2Ffoaf%2F0.1%2Fname%3E+%22%E6%9D%BE%E6%9C > %AC+%E5%90%8E%E5%AD%90%22+.%0D%0A%7D&default-graph- > uri=http%3A%2F%2Frdfa.digitalbazaar.com%2Flibrdfa%2Frdfa2rdf.py%3Furi%3Dhttp% > 3A%2F%2Fwww.w3.org%2F2006%2F07%2FSWD%2FRDFa%2Ftestsuite%2Fxhtml1- > testcases%2F0060.xhtml&stylesheet=%2Fxml-to-html.xsl It starts with "\ufeffASK", i.e. a BOM. You don't want the BOM - this is not a text file, it's a parameter string to a SPARQL request - and the query string be presented in UTF-8. SPARQL is only defined for UTF-8. Remove the BOM and the bomb will not go off. I then get "ASK => true" > > We had not seen this issue until now due to a cut-paste issue in the > Test Harness, which made both the XHTML and SPARQL queries look for "?? > ??" (four question marks separated by a space in the middle). The TCs > were updated to use the proper UTF-8 characters, which broke the SPARQL > engines. Andy, Benji - any chance that this could be fixed in the near > future? > > False Positives in Test Harness with TCs 52, 53, and 58 > ------------------------------------------------------- > > We currently have a couple of bnode tests showing a PASS when they > should be FAIL. All test cases have what we thought was the proper way > to check for a bnode's existence. This bug exists in librdfa and had not > been caught until Dave Beckett pointed out an issue with these Test > Cases and librdfa. I had erroneously replied stating that those test > cases pass in the Test Harness (which they do, and they have always > done). However, they should not be passing. Take TC #52, librdfa and > SPARQL.org as an example. Here's the XHTML: > > ---------------------------------------------------------------------- > <?xml version="1.0" encoding="UTF-8"?> > <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" > "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"> > <html xmlns="http://www.w3.org/1999/xhtml" > xmlns:foaf="http://xmlns.com/foaf/0.1/"> > <head> > <title>Test 0052</title> > </head> > <body> > <p typeof="foaf:Person" resource="http://www.example.org/#me"> > John Doe > </p> > </body> > </html> > ---------------------------------------------------------------------- > > librdfa produces the following RDF/XML, which is incorrect - the node > should not contain an @rdf:about... > > ---------------------------------------------------------------------- > <?xml version="1.0" encoding="utf-8"?> > <rdf:RDF > xmlns:foaf="http://xmlns.com/foaf/0.1/" > xmlns:xh1="http://www.w3.org/1999/xhtml/vocab#" > xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" > > > <foaf:Person rdf:about="http://www.example.org/#me"> > </foaf:Person> > </rdf:RDF> > ---------------------------------------------------------------------- > > but SPARQL.org, surprisingly says that there is a solution to the query. > > ---------------------------------------------------------------------- > ASK WHERE { > _:a > <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> > <http://xmlns.com/foaf/0.1/Person> . > } > ---------------------------------------------------------------------- > That's looks right to me - bNodes in a SPARQL query are variables (unnamed existentals), not constants of the query. For plain RDF, they match like any other variable. That query is the same as ASK WHERE { ?x a <http://xmlns.com/foaf/0.1/Person> } (bNodes match differently over OWL-DL as they can match an anonymous disjunction but this is not OWL-DL). > This leads me to believe that the SPARQL above doesn't do what we think > it does, but I haven't been able to find any documentation detailing how > bnode identification happens in SPARQL queries. > > The question that we're attempting to ask above is "is there a bnode > that has an rdf:type of foaf:Person?", not "is there any node that has > an rdf:type of foaf:Person?". Maybe something like: ASK { ?x a <http://xmlns.com/foaf/0.1/Person> FILTER(isBlank(?x)) } http://www.w3.org/TR/rdf-sparql-query/#func-isBlank Andy > > -- manu > > -- > Manu Sporny > President/CEO - Digital Bazaar, Inc. > blog: DB Launches Medical Record Sales Service with Shepherd Medical > http://blog.digitalbazaar.com/2008/02/24/health2trade/
Received on Saturday, 17 May 2008 20:27:11 UTC