1RDF::Query::ServiceDescUrsieprtiCoonn(t3r)ibuted Perl DoRcDuFm:e:nQtuaetriyo:n:ServiceDescription(3)
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6 RDF::Query::ServiceDescription - Class for describing federated query
7 data sources.
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10 This document describes RDF::Query::ServiceDescription version 2.918.
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13 "new ( $service_uri, %data )"
14 "new_from_uri ( $url )"
15 Creates a new service description object using the DARQ-style
16 service description data located at $url.
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18 "new_with_model ( $model )"
19 Creates a new service description object using the DARQ-style
20 service description data loaded in the supplied $model object.
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22 "url"
23 Returns the endpoint URL of the service.
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25 "size"
26 Returns the number of triples the service claims to have.
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28 "label"
29 Returns the label of the service.
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31 "definitive"
32 Returns true if the endpoint claims to have definitive information.
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34 "capabilities"
35 Returns an ARRAY reference of capabilities (as HASH references) of
36 the service. Each capability will contain information on size,
37 selectivity, any subject-object filter, and required predicate,
38 with the following classes:
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40 $capability->{object_selectivity} # RDF::Trine::Node::Literal xsd:double
41 $capability->{sofilter} # RDF::Query::Expression
42 $capability->{size} # RDF::Trine::Node::Literal xsd:integer
43 $capability->{pred} # RDF::Trine::Node::Resource
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45 "patterns"
46 Returns an ARRAY reference of
47 RDF::Query::Algebra::BasicGraphPattern objects representing common
48 patterns used by the endpoint.
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50 "computed_statement_generator"
51 Returns a closure appropriate for passing to
52 "RDF::Query->add_computed_statement_generator" to generate
53 statement iterators for the remote service.
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55 This closure takes "($query, $bridge, \%bound, $subj, $pred, $obj
56 [, $context ] )" as arguments and returns either "undef" if no
57 statements can be generated given the arguments, or a
58 "RDF::Trine::Iterator::Graph" iterator containing statements
59 matching "$subj, $pred, $obj [, $context ]".
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61 "answers_triple_pattern ( $triple )"
62 Returns true if the service described by this object can answer
63 queries comprised of the supplied triple pattern.
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66 Gregory Todd Williams <gwilliams@cpan.org>
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70perl v5.38.0 2023-07-21 RDF::Query::ServiceDescription(3)