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Parsing data from XML using Ruby and Nokogiri

Submitted by: @import:stackexchange-codereview·Mar 10, 2026·

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xmlparsingusingrubyandfromdatanokogiri

Problem

I have a method that parses XML into an array of hashes.

Here is the original XML:

Here is the final array of hashes:

[{:queuePosition=>"0", :typeID=>"20495", :level=>"3", :startSP=>"2829", :endSP=>"16000", :startTime=>"2013-03-04 16:25:50", :endTime=>"2013-03-05 01:02:20"}, {:queuePosition=>"1", :typeID=>"19767", :level=>"4", :startSP=>"40000", :endSP=>"226275", :startTime=>"2013-03-05 01:02:20", :endTime=>"2013-03-07 06:40:31"}]

Here is the method, which uses Nokogiri for parsing:

def get_training_queue(xml_data)
  queue = []
  xml_data.xpath("//row").each do |skill_in_queue|
    skill = {}
    skill_in_queue.attributes.each do |details|
      skill[details[0].to_s.to_sym] = details[1].to_s
    end
    queue 

This works great, but it feels a bit inelegant.  

I'm curious if there is a better way to create the hashes within the internal loop?

I am calling to_s` because I couldn't figure out a way to pull out just the key/value without doing so, and it 'feels' like I'm missing some more elegant way of doing that.

Solution

Notes:

Use functional Enumerable#map instead of imperative pattern obj = [] + Enumerable#each + Array#




Use Kernel#Hash to build a hash from its pairs. Note that this method is very ugly and some prefer a more OOP approach, in that case check Enumerable#mash from Facets.

Use nokogiri_node.text.




Arguments in blocks can be unpacked.



I'd write:

require 'nokogiri'
require 'facets'

def get_training_queue(xml_data)
  xml_data.xpath("//row").map do |skill_in_queue|
    skill_in_queue.attributes.mash do |name, attribute|
      [name.to_sym, attribute.text]
    end
  end
end


All those

each`s and in-place updates show that you think in imperative terms instead of functional, check this wiki page.

Code Snippets

require 'nokogiri'
require 'facets'

def get_training_queue(xml_data)
  xml_data.xpath("//row").map do |skill_in_queue|
    skill_in_queue.attributes.mash do |name, attribute|
      [name.to_sym, attribute.text]
    end
  end
end

Context

StackExchange Code Review Q#23449, answer score: 4

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