Re: [dotNetRDF-develop] DESCRIBE query and Sesame

[Rob V. <ra...@ec...>]

Ok I will try and get a Sesame instance up and running so I can debug the problem properly.

 

Which error messages in particular are unhelpful, improving error messages is one of the things I have been working on currently so if you could tell me which messages are problematic I’ll aim to improve them.  I guess that you probably mean the generic  "A HTTP error occurred while querying the Store" error that you get from the Sesame connector?  The problem here is that when making the query over HTTP I don’t necessarily get a coherent response back from the server, I could potentially extract the returned response text (if any) from the response and append that to the exception message if that would help?  Though I notice that the server doesn’t necessarily return any error messages in the response depending on where the error is in the query.

 

Rob

 

From: Sergey Novikov [mailto:ser...@gm...] 
Sent: 08 September 2010 10:59
To: Rob Vesse
Subject: Re: DESCRIBE query and Sesame

 

Hi, Rob.

 

Exported from SVN latest version today. Exception exist and message the same.

 

By the way. When I execute sparql queries that contains errors - messages from exceptions is not helpfull at all. Don't know if it possible to do something, but any improvements would be great.


Best regards,

Sergey Novikov



On Tue, Sep 7, 2010 at 12:45 PM, Rob Vesse <ra...@ec...> wrote:

Hi Sergey

 

Think I have fixed this bug in SVN as of revision 970.  Can you confirm for me whether this is now fixed as I don’t have an instance of plain Sesame itself to test against (I test against AllegroGraph which implements the Sesame HTTP protocol).

 

By the way I see from your stack trace you may still be using dotNetRDF 0.2.2?  If you are you should consider upgrading to the 0.3.0 release or the latest SVN builds asap as they contain many bug fixes and improvements particularly with regards to adding many more SPARQL 1.1 Query and Update features.

 

Best Regards,

 

Rob Vesse

 

From: Sergey Novikov [mailto:ser...@gm...] 
Sent: 03 September 2010 16:11
To: ra...@ec...
Subject: DESCRIBE query and Sesame

 

Hi, Rob

 

I'm having some difficulties with DESCRIBE construction in DotNetRDF.

 

For instance, this simple query:

 

return store.ExecuteQuery(@"DESCRIBE <http://test.com/TestPerson1>");

 

cause exception:

 

[VDS.RDF.Parsing.RdfParseException] = {"The input was not a single boolean value as a String"}

 

with stack trace:

 

   at VDS.RDF.Parsing.SparqlBooleanParser.Load(SparqlResultSet results, StreamReader input) in D:\Upload\!DevelopSemantic\RipicsSemantic\Semantic\dotNetRDF022Alpha2010-08-18\Trunk\Libraries\core\Parsing\SparqlBooleanParser.cs:line 87

   at VDS.RDF.Storage.SesameHttpProtocolConnector.Query(String sparqlQuery) in D:\Upload\!DevelopSemantic\RipicsSemantic\Semantic\dotNetRDF022Alpha2010-08-18\Trunk\Libraries\core\Storage\SesameHttpProtocolConnector.cs:line 169

   at VDS.RDF.NativeTripleStore.ExecuteQuery(String query) in D:\Upload\!DevelopSemantic\RipicsSemantic\Semantic\dotNetRDF022Alpha2010-08-18\Trunk\Libraries\core\Core\NativeTripleStore.cs:line 78

   at CommonMethods.RDFBasicIO.SPARQLRequest(String query) in D:\Upload\!DevelopSemantic\RipicsSemantic\AssetManagement\Common\RDFBasicIO.cs:line 105

 

I've tested this query through sesame web interface and it work fine returning me couple relevant results. 

 

Can you find what is wrong?

 

Thank you.


Best regards,

Sergey Novikov