[redland] perl or commandline interface to raptor?

[Dave Beckett]

>>>Dan Brickley said:
> 
> Dave,
> 
> I'm trying to plug Raptor (via Redland Perl or commandline ntriple output)
> into some Perl stuff I'm working on. Any chance of a quick HOWTO for
> getting triples back from URI or chunk-of-markup input, eg. via the Perl
> interface or commandline?

The distribution perl/example.pl code can be cut down to do this.
Customising it for raptor, and deleting all error checking gives:

use RDF;
my $uri=new RDF::URI("file:$test_file");
my $parser=new RDF::Parser('raptor');
my $stream=$parser->parse_as_stream($uri,$uri);
while(!$stream->end) {
  print "Statement: ",$stream->next->as_string,"\n";
}
$stream=undef;

You'll need to get the content to a local file since redland doesn't
do URI retrieval; but there are Perl modules for that.  In which
case, change the 
  my $stream=$parser->parse_as_stream($uri,$uri);
to
  my $stream=$parser->parse_as_stream($uri,$base_uri);
where $uri is the URI of the local file and $base_uri is the remote URI.

However, the above doesn't generate N-Triples output.


> .. I had a quick stab at compiling
> http://www.redland.opensource.ac.uk/raptor/rdfdump.c but was put off by
> all the autoconf stuff. BTW you ship an rdfdump.c in the repat directory
> too (Jason's), which I found a little confusing.

Imagination failed me in naming there.  rdfparse?
Not too tricky to build:

  ./configure
  make rdfdump
  ./rdfdump -o ntriples file:local-file baseURI

again, you'll need to get the baseURI content into local-file.

> In general, I reckon it'd be hand for all RDF parsers to be callable on
> the commandline via some agreed conventions, outputting ntriples. To date
> I've mostly used Eric P's Perl one, but now I find I need to parse/load
> 16Mb of RDF annotations it is time to shift to a C parser...

Dave