Class: Traject::MarcReader

Inherits:
Object
  • Object
show all
Includes:
Enumerable
Defined in:
lib/traject/marc_reader.rb

Overview

A Reader class that can be used with Traject::Indexer.reader, to read MARC records.

Includes Enumerable for convenience.

Reads in Marc records using ruby marc. Depends on config variables to determine what serialization type to expect, and other parameters controlling de-serialization.

NOTE: MarcReader can not handle Marc8 encoding. If you need to read binary records in MARC8, use Traject::Marc4JReader instead.

Settings:

["marc_source.type"]  serialization type. default 'binary'
              * "binary". Actual marc.
              * "xml", MarcXML
              * "json". (NOT YET IMPLEMENTED) The "marc-in-json" format, encoded as newline-seperated
                json. A simplistic newline-seperated json, with no comments
                allowed, and no unescpaed internal newlines allowed in the json
                objects -- we just read line by line, and assume each line is a
                marc-in-json. http://dilettantes.code4lib.org/blog/2010/09/a-proposal-to-serialize-marc-in-json/
["marc_reader.xml_parser"] For XML type, which XML parser to tell Marc::Reader
                           to use. Anything recognized by Marc::Reader :parser
                           argument. By default, asks Marc::Reader to take
                           it's best guess as to highest performance available
                           installed option.

Can NOT yet read Marc8, input is always assumed UTF8.

Constant Summary collapse

@@best_xml_parser = 
MARC::XMLReader.best_available

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(input_stream, settings) ⇒ MarcReader

Returns a new instance of MarcReader.



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# File 'lib/traject/marc_reader.rb', line 39

def initialize(input_stream, settings)
  @settings = Traject::Indexer::Settings.new settings
  @input_stream = input_stream
end

Instance Attribute Details

#input_stream ⇒ Object (readonly)

Returns the value of attribute input_stream.



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# File 'lib/traject/marc_reader.rb', line 35

def input_stream
  @input_stream
end

#settings ⇒ Object (readonly)

Returns the value of attribute settings.



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# File 'lib/traject/marc_reader.rb', line 35

def settings
  @settings
end

Instance Method Details

#each(*args, &block) ⇒ Object 



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# File 'lib/traject/marc_reader.rb', line 60

def each(*args, &block)
  self.internal_reader.each(*args, &block)
end

#internal_reader ⇒ Object

Creates proper kind of ruby MARC reader, depending on settings or guesses.



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# File 'lib/traject/marc_reader.rb', line 46

def internal_reader
  unless defined? @internal_reader
    @internal_reader =
      case settings["marc_source.type"]
      when "xml"
        parser = settings["marc_reader.xml_parser"] || @@best_xml_parser
        MARC::XMLReader.new(self.input_stream, :parser=> parser)
      else
        MARC::Reader.new(self.input_stream)
      end
  end
  return @internal_reader
end