Re: Fuseki - Reasoning on request

[Andy Seaborne]

On 22/04/16 10:43, Dominique Vandensteen wrote:

Hi,
I've configured my fuseki to use reasoning. Is it possible to, by default
disable this, and enable it by passing a parameter to the sparql request?

Dominique



Not in the general case.  If the data is read-onlyFuseki (or you are 
careful and only update through the inference service), you can have two 
sets of services over one dataset.  This is best supported in the 
current development builds - it's not in a release in a reliable way.


Andy

Re: Fuseki: how to configure direct dereferencing?

[Andy Seaborne]

Fuseki does not support much for dereferencing inside a dataset.  The 
question is what should be returned?


1/
A simple case is "DESCRIBE " (that can be done by a reverse proxy 
rewrite (I think).


2/
Graph Store Protocol : Fuseki support both direct and indirect naming.

A direct name is

http://www.example.com/mydataset/path/resource

(caution - service names take precedence - 
http://www.example.com/mydataset/sparql for example).


That names a graph in the dataset and you get back the whole graph. So 
to use it for dereferencing a URI, the graph naming needs to correspond 
to resources.




What did you want back from a dereference request? (what are the limits 
on the RDF?)


There seem to be a lot of choices on what to return (include lists?) so 
a front end dereference service might be the ideal set up.


Andy

rdfs:seeAlso Pubby ?

On 22/04/16 11:05, Frans Knibbe wrote:

Hello,

I am sorry to have to return to this question. It seems I am still having
problems with dereferencing URIs. In my first message I described loading
Fuseki with a sample RDF dataset and then trying dereferencing the URIs in
that dataset. I managed to get it working for the URI of the dataset itself
(http://www.example.com/mydataset/data in the example), but a test with an
individual resource in the dataset, for example http://www.example.com/
mydataset/data/something, failed.

It could be that I am trying to get something out of Fuseki for which it
was not intended. So I wonder: Is dereferencing URIs of RDF-data (not just
graphs) stored in some kind of Jena data store supported by Fuseki (or
perhaps another Jena component) by configuration only?

Regards,
Frans

2016-04-15 15:10 GMT+02:00 Frans Knibbe :


Hello again,

By coincidence I seem to have just stumbled across the answer to my
question. In another Apache HTTPD configuration file I noticed the
ProxyPreserveHost directive. The default setting is Off, but when enabled
(ProxyPreserveHost On), the original host name will be sent to the Fuseki
server. And that does the trick.

I am glad it is working now, and that I did not have to resort to
mod_rewrite.

Regards,
Frans



2016-04-15 14:26 GMT+02:00 Frans Knibbe :


Hello,

Being new to Jena and Fuseki, I am trying to use Fuseki as both a SPARQL
server and a means to directy access data with HTTP GET.

I have got Fuseki (version 1.3.1) running on http://localhost:3030. I
want data to be accessible to the outside world on http://www.example.com
(well, not really, but this is an example). In my Apache web server I have
set

ServerName www.example.com
ProxyPass / http://localhost:3030/
ProxyPassReverse / http://localhost:3030/

I have started Fuseki like this:
./fuseki-server -v --update --mem /mydataset

And I loaded small sample dataset like this:

s-put -v http://www.example.com/mydataset/data
http://www.example.com/mydataset/data mydataset.ttl

Getting the data out via s-get works. What does not work is getting the
data via HTTP:

curl -g -H "Accept: text/turtle" http://www.example.com/mydataset/data

This results in Fuseki reporting the following error:

Error 404: No such graph: 

How could this problem be resolved? Could I change something in my web
server configuration or in my Fuseki settings to make this work?

Regards,
Frans

Imported ontology handling

[Laurent Rucquoy]

Hello,

I want to manage a TDB notably to store observations which use terms
defined in an external ontology.

This ontology is defined in OWL files available on the following web page:
https://bioportal.bioontology.org/ontologies/RADLEX?p=summary

Example of OWL file used:
- 3.13.1 version :
http://data.bioontology.org/ontologies/RADLEX/submissions/36/download?apikey=8b5b7825-538d-40e0-9e9e-5ab9274a9aeb
- 3.12 version :
http://data.bioontology.org/ontologies/RADLEX/submissions/31/download?apikey=8b5b7825-538d-40e0-9e9e-5ab9274a9aeb


What is the best practice to handle the ontology use ?

My idea is to import the OWL file as a named model in my TDB whereas my
instances are stored in the default model. These instances will be linked
to the ontology through  resources (where
RID is the local id of terms defined in this ontology)

When I will have to reason with the ontology, I will use a 'work' model
resulting from the union of the ontology named model and the default model.


My questions:

1) Is this the right way to reason with imported ontologies (i.e. the
default model to store the instances, named models used to import different
versions of an ontology and a 'work' model resulting from the union of
default model and named model) ?


2) How can I handle the different versions of OWL files ?

e.g. in one version of this ontology, the RID31872 term is identified by the
 uri
while the same term is identified by the
 uri

Which information will be the more useful to store in my default model to
be able to link to the corresponding term in the different versions of the
ontology since the base uri could change from one version to the other
(while the local part is still the same) ?


Thank you in advance for your help.

Sincerely,
Laurent

Re: Fuseki: how to configure direct dereferencing?

[Paul Hermans]

Hi Frans,

We always put something in front of Fuseki for the dereferencing way of 
publishing.
In our case the highly configurable NetKernel LOD edition. 
Have also a look at Graphity.


Kind Regards,
Paul Hermans













On 22/04/16 12:05, "Frans Knibbe"  wrote:

>Hello,
>
>I am sorry to have to return to this question. It seems I am still having
>problems with dereferencing URIs. In my first message I described loading
>Fuseki with a sample RDF dataset and then trying dereferencing the URIs in
>that dataset. I managed to get it working for the URI of the dataset itself
>(http://www.example.com/mydataset/data in the example), but a test with an
>individual resource in the dataset, for example http://www.example.com/
>mydataset/data/something, failed.
>
>It could be that I am trying to get something out of Fuseki for which it
>was not intended. So I wonder: Is dereferencing URIs of RDF-data (not just
>graphs) stored in some kind of Jena data store supported by Fuseki (or
>perhaps another Jena component) by configuration only?
>
>Regards,
>Frans
>
>2016-04-15 15:10 GMT+02:00 Frans Knibbe :
>
>> Hello again,
>>
>> By coincidence I seem to have just stumbled across the answer to my
>> question. In another Apache HTTPD configuration file I noticed the
>> ProxyPreserveHost directive. The default setting is Off, but when enabled
>> (ProxyPreserveHost On), the original host name will be sent to the Fuseki
>> server. And that does the trick.
>>
>> I am glad it is working now, and that I did not have to resort to
>> mod_rewrite.
>>
>> Regards,
>> Frans
>>
>>
>>
>> 2016-04-15 14:26 GMT+02:00 Frans Knibbe :
>>
>>> Hello,
>>>
>>> Being new to Jena and Fuseki, I am trying to use Fuseki as both a SPARQL
>>> server and a means to directy access data with HTTP GET.
>>>
>>> I have got Fuseki (version 1.3.1) running on http://localhost:3030. I
>>> want data to be accessible to the outside world on http://www.example.com
>>> (well, not really, but this is an example). In my Apache web server I have
>>> set
>>>
>>> ServerName www.example.com
>>> ProxyPass / http://localhost:3030/
>>> ProxyPassReverse / http://localhost:3030/
>>>
>>> I have started Fuseki like this:
>>> ./fuseki-server -v --update --mem /mydataset
>>>
>>> And I loaded small sample dataset like this:
>>>
>>> s-put -v http://www.example.com/mydataset/data
>>> http://www.example.com/mydataset/data mydataset.ttl
>>>
>>> Getting the data out via s-get works. What does not work is getting the
>>> data via HTTP:
>>>
>>> curl -g -H "Accept: text/turtle" http://www.example.com/mydataset/data
>>>
>>> This results in Fuseki reporting the following error:
>>>
>>> Error 404: No such graph: 
>>>
>>> How could this problem be resolved? Could I change something in my web
>>> server configuration or in my Fuseki settings to make this work?
>>>
>>> Regards,
>>> Frans
>>>
>>>
>>

Re: Fuseki: how to configure direct dereferencing?

[Frans Knibbe]

Hello,

I am sorry to have to return to this question. It seems I am still having
problems with dereferencing URIs. In my first message I described loading
Fuseki with a sample RDF dataset and then trying dereferencing the URIs in
that dataset. I managed to get it working for the URI of the dataset itself
(http://www.example.com/mydataset/data in the example), but a test with an
individual resource in the dataset, for example http://www.example.com/
mydataset/data/something, failed.

It could be that I am trying to get something out of Fuseki for which it
was not intended. So I wonder: Is dereferencing URIs of RDF-data (not just
graphs) stored in some kind of Jena data store supported by Fuseki (or
perhaps another Jena component) by configuration only?

Regards,
Frans

2016-04-15 15:10 GMT+02:00 Frans Knibbe :

> Hello again,
>
> By coincidence I seem to have just stumbled across the answer to my
> question. In another Apache HTTPD configuration file I noticed the
> ProxyPreserveHost directive. The default setting is Off, but when enabled
> (ProxyPreserveHost On), the original host name will be sent to the Fuseki
> server. And that does the trick.
>
> I am glad it is working now, and that I did not have to resort to
> mod_rewrite.
>
> Regards,
> Frans
>
>
>
> 2016-04-15 14:26 GMT+02:00 Frans Knibbe :
>
>> Hello,
>>
>> Being new to Jena and Fuseki, I am trying to use Fuseki as both a SPARQL
>> server and a means to directy access data with HTTP GET.
>>
>> I have got Fuseki (version 1.3.1) running on http://localhost:3030. I
>> want data to be accessible to the outside world on http://www.example.com
>> (well, not really, but this is an example). In my Apache web server I have
>> set
>>
>> ServerName www.example.com
>> ProxyPass / http://localhost:3030/
>> ProxyPassReverse / http://localhost:3030/
>>
>> I have started Fuseki like this:
>> ./fuseki-server -v --update --mem /mydataset
>>
>> And I loaded small sample dataset like this:
>>
>> s-put -v http://www.example.com/mydataset/data
>> http://www.example.com/mydataset/data mydataset.ttl
>>
>> Getting the data out via s-get works. What does not work is getting the
>> data via HTTP:
>>
>> curl -g -H "Accept: text/turtle" http://www.example.com/mydataset/data
>>
>> This results in Fuseki reporting the following error:
>>
>> Error 404: No such graph: 
>>
>> How could this problem be resolved? Could I change something in my web
>> server configuration or in my Fuseki settings to make this work?
>>
>> Regards,
>> Frans
>>
>>
>

Fuseki - Reasoning on request

[Dominique Vandensteen]

Hi,
I've configured my fuseki to use reasoning. Is it possible to, by default
disable this, and enable it by passing a parameter to the sparql request?

Dominique