Whole structure is accessible through ONIX::ONIXMessage object :

message = ONIX::ONIXMessage.new
message.parse("onix_file.xml")
# first product
pp message.products.first
# first identifier of first product
pp message.products.first.identifiers.first

Ruby elements variables are underscored, lowercase of ONIX tags (Product -> product, DescriptiveDetail -> descriptive_detail) and pluralized in case of array (ProductSupply -> product_supplies).

High level methods give abstracted and simplified access to the most important data.
See https://www.rubydoc.info/gems/im_onix/ONIX/Product for high level API rdoc and onix_pp.rb, onix3_to_onix2.rb and onix3_to_onix3.rb sample in bin/

Usage :

onix_pp.rb onix.xml
onix3_to_onix2.rb onix.xml
onix3_to_onix3.rb onix.xml

Launch this command:

bundle exec rake test

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