Contents

require 'open-uri'

module JSON::LD
  ##
  # A JSON-LD parser in Ruby.
  #
  # @see http://json-ld.org/spec/ED/20110507/
  # @author [Gregg Kellogg](http://greggkellogg.net/)
  class Reader < RDF::Reader
    format Format
    
    ##
    # Override normal symbol generation
    def self.to_sym
      :jsonld
    end

    ##
    # Initializes the RDF/JSON reader instance.
    #
    # @param  [IO, File, String]       input
    # @param  [Hash{Symbol => Object}] options
    #   any additional options (see `RDF::Reader#initialize`)
    # @yield  [reader] `self`
    # @yieldparam  [RDF::Reader] reader
    # @yieldreturn [void] ignored
    # @raise [RDF::ReaderError] if the JSON document cannot be loaded
    def initialize(input = $stdin, options = {}, &block)
      options[:base_uri] ||= options[:base]
      super do
        @options[:base] ||= base_uri.to_s if base_uri
        begin
          @doc = JSON.load(input)
        rescue JSON::ParserError => e
          raise RDF::ReaderError, "Failed to parse input document: #{e.message}" if validate?
          @doc = JSON.parse("{}")
        end

        if block_given?
          case block.arity
            when 0 then instance_eval(&block)
            else block.call(self)
          end
        end
      end
    end

    ##
    # @private
    # @see   RDF::Reader#each_statement
    def each_statement(&block)
      JSON::LD::API.toRDF(@doc, @options[:context], @options).each do |statement|
        # If RDF version is 1.0, fold literals with xsd:string to be just simple literals
        statement.object.datatype = nil if
          RDF::VERSION.to_s < "1.1" &&
          statement.object.literal? &&
          statement.object.datatype == RDF::XSD.string
        block.call(statement)
      end
    end

    ##
    # @private
    # @see   RDF::Reader#each_triple
    def each_triple(&block)
      each_statement do |statement|
        block.call(*statement.to_triple)
      end
    end
  end
end

Version data entries

3 entries across 3 versions & 1 rubygems

Version	Path
json-ld-1.0.5	lib/json/ld/reader.rb
json-ld-1.0.4	lib/json/ld/reader.rb
json-ld-1.0.3	lib/json/ld/reader.rb