examples don't work; "SPARQL engine unsupported"

[Mike Travers]

The examples given in the introductory doc doesn't work

Download:
http://the-blank.net/files/activerdf/activerdf_example_sparql.rb

$ ruby /misc/downloads/activerdf_example_sparql.rb
/usr/local/lib/ruby/gems/1.8/gems/activerdf_sparql-1.3.5/lib/activerdf_sparql/sparql.rb:40:in `initialize': SPARQL engine unsupported (ActiveRdfError)
 from /usr/local/lib/ruby/gems/1.8/gems/activerdf-1.6.8/lib/active_rdf/federation/connection_pool.rb:146:in `new'
 from /usr/local/lib/ruby/gems/1.8/gems/activerdf-1.6.8/lib/active_rdf/federation/connection_pool.rb:146:in `send'
 from /usr/local/lib/ruby/gems/1.8/gems/activerdf-1.6.8/lib/active_rdf/federation/connection_pool.rb:146:in `create_adapter'
 from /usr/local/lib/ruby/gems/1.8/gems/activerdf-1.6.8/lib/active_rdf/federation/connection_pool.rb:76:in `add_data_source'
 from /misc/downloads/activerdf_example_sparql.rb:4

inserting an :engine parameter helps (although the server won't accept the connection)

[Eyal Oren (ikbeneyal)]

I don't know what the files on http://the-blank.net are. The official ActiveRDF distribution on RubyForge contains test code and examples including code to access a SPARQL endpoint. That code works. It looks as if the code you mention from http://the-blank.net is old and doesn't comply to the ActiveRDF API. That's not a bug in ActiveRDF. Please have a look at the test and example code in the official distribution.

With respect to the endpoint used in those examples (http://dbpedia.org/sparql), that endpoint is indeed refusing connections right now. I don't know why (it's an open data endpoint and not under our control).

[Mike Travers (mt-alum)]

Thanks for the response...that link was on an ActiveRDf page, but I
can't find it now. I found similar bad examples from the ActiveRDF doc
site, for instance on this page:
  http://wiki.activerdf.org/ActiveRDF

I found my way around the problem, just trying to improve the docs for others.

Mike

On Jan 24, 2008 1:44 AM, Eyal Oren <email address hidden> wrote:
> I don't know what the files on http://the-blank.net are. The official
> ActiveRDF distribution on RubyForge contains test code and examples
> including code to access a SPARQL endpoint. That code works. It looks
> as if the code you mention from http://the-blank.net is old and doesn't
> comply to the ActiveRDF API. That's not a bug in ActiveRDF. Please have
> a look at the test and example code in the official distribution.
>
> With respect to the endpoint used in those examples
> (http://dbpedia.org/sparql), that endpoint is indeed refusing
> connections right now. I don't know why (it's an open data endpoint and
> not under our control).
>
> ** Changed in: activerdf
> Assignee: (unassigned) => Eyal Oren (ikbeneyal)
> Status: New => Invalid
>
>
> --
> examples don't work; "SPARQL engine unsupported"
> https://bugs.launchpad.net/bugs/185464
> You received this bug notification because you are a direct subscriber
> of the bug.
>

[Mike Travers (mt-alum)]

While I've got your attention...it looks like ActiveRDF doesn't
support named graphs (SPARQL FROM clauses); is this right? I reported
this as an issue a while back:
  https://bugs.launchpad.net/activerdf/+bug/177782
I might go ahead and add this myself, although I'm fairly new to the
Ruby universe.

On Jan 24, 2008 1:44 AM, Eyal Oren <email address hidden> wrote:
> I don't know what the files on http://the-blank.net are. The official
> ActiveRDF distribution on RubyForge contains test code and examples
> including code to access a SPARQL endpoint. That code works. It looks
> as if the code you mention from http://the-blank.net is old and doesn't
> comply to the ActiveRDF API. That's not a bug in ActiveRDF. Please have
> a look at the test and example code in the official distribution.
>
> With respect to the endpoint used in those examples
> (http://dbpedia.org/sparql), that endpoint is indeed refusing
> connections right now. I don't know why (it's an open data endpoint and
> not under our control).
>
> ** Changed in: activerdf
> Assignee: (unassigned) => Eyal Oren (ikbeneyal)
> Status: New => Invalid
>
>
> --
> examples don't work; "SPARQL engine unsupported"
> https://bugs.launchpad.net/bugs/185464
> You received this bug notification because you are a direct subscriber
> of the bug.
>

[Jim Amsden (jimamsden)]

I'm getting the same problem on Mac OS X 10.6.1, activerdf 1.6.11 and activerdf_sparql 1.3.6, with Ruby 1.6.7. What is the work-around?