PublicShow sourcerdf_http_plugin.pl -- RDF HTTP Plugin

This module allows loading data into the semantic web library directly from an HTTP server. The following example loads the RDF core data into the RDF database.

:- use_module(library(semweb/rdf_db)).
:- use_module(library(semweb/rdf_http_plugin)).

    ...,
    rdf_load('http://www.w3.org/1999/02/22-rdf-syntax-ns')
Source rdf_db:rdf_open_hook(+Scheme, +URL, +HaveModified, -Stream, -Cleanup, -Modified, -Format, +Options) is semidet[multifile]
Load hook implementation for HTTP(S) URLs.
Arguments:
HaveModified- is bound to a timestamp (number) if we already have a copy and that copy was modified at HaveModified.
Modified- is bound to unknown, not_modified or a timestamp.
Source rdf_content_type(?MediaType:atom, ?QualityValue:between(0.0,1.0), ?Format:rdf_format) is nondet[multifile]
Quality values are intended to be used in accordance with RFC 2616. Quality values are determined based on the following criteria:
LabelCriterionValue
ASupported RDF parser0.43
BRDF-specific content type0.33
COfficial content type0.23

For example, text/turtle has quality value 0.99 because it is an official content type that is RDF-specific and that has a parser in Semweb.

This intentionally allows the user to add another content type with a higher Q-value (i.e., >0.99).

Deduce the RDF encoding from the mime-type. This predicate is defined as multifile such that the user can associate additional content types to RDF formats.

See also
- Discussion http://richard.cyganiak.de/blog/2008/03/what-is-your-rdf-browsers-accept-header/
- N-Quadruples http://www.w3.org/ns/formats/N-Quads
- N-Triples http://www.w3.org/ns/formats/N-Triples
- N3 http://www.w3.org/ns/formats/N3
- RDFa http://www.w3.org/ns/formats/RDFa
- TriG http://www.w3.org/ns/formats/TriG
- Turtle http://www.w3.org/ns/formats/Turtle
- XML/RDF http://www.w3.org/ns/formats/RDF_XML
bug
- The turtle parser only parses a subset of n3. (The N3 format is treated as if it were Turtle.)