On 14/09/11 17:26, Tim Harsch wrote:
I used the TDB example config to create the config below. It should
allow me to use FROM and FROM NAMED clauses to alter the dataset queried
from the TDB quads, (with named graphs loaded). But not attempt to load
RDF from the web. It appears it attempts to still fetch documents from
web, as I usually get URL not found message from Joseki. Is this a bug?
or something I'm doing wrong?
Thanks,
Tim
Hi Tim,
Joseki does dataset processing before the request gets to TDB hence the
attempt to load from the web.
Fuseki (=Joseki4) should this right. In Fuseki, the handling of
FROM-web loading is delegated to service. There are two kinds of
service - dataset-backed and a general executor that has no background
data. That means the one case of having FROM-web loading AND a fixed
dataset isn't supported on the same service endpoint; it can be added
but I haven't seen it used to effect.
So in Fuseki, the dataset gets to see the whole request, and decide what
to do with FROM. And so TDB handles it as a restriction over the
configured dataset.
While we get sorted out with Apache release process, the current
development snapshot of 0.2.1 is the best to use (include draft
configuration file support, simpler but not compatible with Joseki).
Andy
@prefix rdfs:<http://www.w3.org/2000/01/rdf-schema#> .
@prefix rdf:<http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix xsd:<http://www.w3.org/2001/XMLSchema#> .
@prefix module:<http://joseki.org/2003/06/module#> .
@prefix joseki:<http://joseki.org/2005/06/configuration#> .
@prefix ja:<http://jena.hpl.hp.com/2005/11/Assembler#> .
@prefix sdb:<http://jena.hpl.hp.com/2007/sdb#> .
@prefix tdb:<http://jena.hpl.hp.com/2008/tdb#> .
<> rdfs:label "Joseki Configuration File - TDB example" .
# Stripped down to support one service that exposes an
# TDB store as a SPARQL endpoint for query.
[] rdf:type joseki:Server .
## --------------------------------------------------------------
## Services
<#service1>
rdf:type joseki:Service ;
rdfs:label "SPARQL-TDB" ;
joseki:serviceRef "sparql" ; # web.xml must route this name to
Joseki
joseki:dataset<#dataset> ;
joseki:processor joseki:MyProcessorSPARQL ;
.
## --------------------------------------------------------------
## Datasets
## Initialize TDB.
[] ja:loadClass "com.hp.hpl.jena.tdb.TDB" .
tdb:DatasetTDB rdfs:subClassOf ja:RDFDataset .
tdb:GraphTDB rdfs:subClassOf ja:Model .
## ---- A whole dataset managed by TDB
<#dataset> rdf:type tdb:DatasetTDB ;
tdb:location "icdTest" ;
.
## --------------------------------------------------------------
## Processors
joseki:MyProcessorSPARQL
rdfs:label "SPARQL processor with no web loading" ;
rdf:type joseki:Processor ;
module:implementation
[ rdf:type joseki:ServiceImpl ;
module:className<java:org.joseki.processors.SPARQL>
] ;
# This processor will accept queries with FROM/FROM NAMED
joseki:allowExplicitDataset "true"^^xsd:boolean ;
joseki:allowWebLoading "false"^^xsd:boolean ;
# The database is safe for MRSW (multiple-reader, single-writer).
joseki:lockingPolicy joseki:lockingPolicyMRSW ;
.
