Class: ONIX::Reader

Inherits:
Object
  • Object
show all
Includes:
Enumerable
Defined in:
lib/onix/reader.rb

Overview

This is the primary class for reading data from an ONIX file, and there’s really not much to it

Each file should contain a single header, and 1 or more products:

reader = ONIX::Reader.new("somefile.xml")

puts reader.header.inspect

reader.each do |product|
  puts product.inspect
end

The header will be returned as an ONIX::Header object, and the product will be an ONIX::Product.

The ONIX::Product class can be a bit of a hassle to work with, as data can be nested in it fairly deeply. To wrap all the products returned by the reader in a shim that provides simple accessor access to common attributes, pass the shim class as a second argument

reader = ONIX::Reader.new("somefile.xml", ONIX::APAProduct)

puts reader.header.inspect

reader.each do |product|
  puts product.inspect
end

APAProduct stands for Australian Publishers Association and provides simple access to the ONIX attributes that are commonly used in the Australian market.

As well as accessing the file header, there are handful of other read only attributes that might be useful

reader = ONIX::Reader.new("somefile.xml", ONIX::APAProduct)

puts reader.version
puts reader.xml_lang
puts reader.xml_version
puts reader.encoding

The version attribute is particuarly useful. There are multiple revisions of the ONIX spec, and you may need to handle the file differently based on what version it is.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(input, product_klass = ::ONIX::Product) ⇒ Reader

Returns a new instance of Reader.



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# File 'lib/onix/reader.rb', line 58

def initialize(input, product_klass = ::ONIX::Product)
  if input.kind_of?(String)
    @file   = File.open(input, "r")
    @reader = Nokogiri::XML::Reader(@file) { |cfg| cfg.dtdload.noent }
  elsif input.kind_of?(IO)
    @reader = Nokogiri::XML::Reader(input) { |cfg| cfg.dtdload.noent }
  else
    raise ArgumentError, "Unable to read from file or IO stream"
  end

  @product_klass = product_klass

  @release = find_release
  @header = find_header

  @xml_lang    ||= @reader.lang
  @xml_version ||= @reader.xml_version.to_f
end

Instance Attribute Details

#header ⇒ Object (readonly)

Returns the value of attribute header.



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# File 'lib/onix/reader.rb', line 56

def header
  @header
end

#release ⇒ Object (readonly)

Returns the value of attribute release.



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# File 'lib/onix/reader.rb', line 56

def release
  @release
end

Instance Method Details

#close ⇒ Object 



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# File 'lib/onix/reader.rb', line 92

def close
  @reader.close if @reader
end

#each(&block) ⇒ Object

Iterate over all the products in an ONIX file



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# File 'lib/onix/reader.rb', line 79

def each(&block)
  @reader.each do |node|
    if @reader.node_type == 1 && @reader.name == "Product"
      str = @reader.outer_xml
      if str.nil?
        yield @product_klass.new
      else
        yield @product_klass.from_xml(str)
      end
    end
  end
end