class RDF::TriG::Format

TriG format specification.

@example Obtaining an TriG format class

RDF::Format.for("etc/foaf.trig")
RDF::Format.for(:file_name      => "etc/foaf.trig")
RDF::Format.for(file_extension: "trig")
RDF::Format.for(:content_type   => "application/trig")

@example Obtaining serialization format MIME types

RDF::Format.content_types      #=> {"application/trig" => [RDF::TriG::Format]}

@example Obtaining serialization format file extension mappings

RDF::Format.file_extensions    #=> {trig: "application/trig"}

@see www.w3.org/TR/rdf-testcases/#ntriples

Public Class Methods

detect(sample) click to toggle source

Sample detection to see if it matches TriG

Use a text sample to detect the format of an input file. Sub-classes implement a matcher sufficient to detect probably format matches, including disambiguating between other similar formats.

@param [String] sample Beginning several bytes (~ 1K) of input. @return [Boolean]

# File lib/rdf/trig/format.rb, line 37
def self.detect(sample)
  !!sample.match(%r(
    (?:
      (?:\s*(?:(?:<[^>]*>) | (?:\w*:\w+) | (?:"[^"]*")))?           # IRIref
      \s*\{                                                         # Graph Start
      (?:
        (?:\s*(?:(?:<[^>]*>) | (?:\w*:\w+) | (?:"[^"]*"))\s*[,;]) ||
        (?:\s*(?:(?:<[^>]*>) | (?:\w*:\w+) | (?:["']+[^"']*["']+))){3}
      )*                                                            # triples
      [\s\.]*\}\s*                                                  # Graph end
    )
  )mx) && !(
    sample.match(%r(@keywords|=)) ||                                # N3
    sample.match(%r(<(?:\/|html|rdf))i) ||                          # HTML, RDF/XML
    sample.match(%r(^(?:\s*<[^>]*>){4}.*\.\s*$)) ||                 # N-Quads
    sample.match(%r("@(context|subject|iri)"))                      # JSON-LD
  )
end