convert itunes music library to database sqlite3 using ruby

xml2db.rb

#!/usr/bin/env ruby 
=begin
  * Name: xml.rb
  * Description   parses xml iTunes Music Library and inserts into database
    so other apps can use, rather than each time parsing xml file
  * Author: Original - Aaron Patterson (xml parsing portion)
    http://groups.google.com/group/nokogiri-talk/browse_thread/thread/97973521c6f5f0dc
  *         Additions by rkumar
  * Date:  2010-08-04
  * License:
    Same as Ruby's License (http://www.ruby-lang.org/LICENSE.txt)

  * create the itunes.sqlite file using http://gist.github.com/508400
  @usage 
   ./xml2db.rb iTunes\ Music\ Library.xml
=end
require 'rubygems'
require 'nokogiri'
require 'sqlite3'
require 'arrayfields'
require "highline/import"

def table_insert_hash db, table, hash
  str = "INSERT INTO #{table} ("
  qstr = [] # question marks
  fields = [] # field names
  bind_vars = [] # values to insert
  hash.each_pair { |name, val| 
    fields << name
    bind_vars << val
    qstr << "?"
  }
  fstr = fields.join(",")
  str << fstr
  str << ") values ("
  str << qstr.join(",")
  str << ")"
  #puts str
  db.execute(str, *bind_vars)
  rowid = db.get_first_value( "select last_insert_rowid();")
  return rowid
end

counter = 0
dbname = "itunes.sqlite"
raise " #{dbname} must exist with tables in it - use http://gist.github.com/508400"
db = SQLite3::Database.new(dbname)
list = []
filename = ARGV[0] || File.expand_path("~/Music/iTunes/iTunes Music Library.xml")
doc = Nokogiri::XML(File.open(filename, 'r'))

# Find each dictionary item and loop through it
doc.xpath('/plist/dict/dict/dict').each do |node|

  #hash     = {}
  hash     = Hash.new("Not found")
  last_key = nil

  # Stuff the key value pairs in to hash.  We know a key is followed by
  # a value, so we'll just skip blank nodes, save the key, then when we
  # find the value, add it to the hash
  node.children.each do |child|

    next if child.blank? # Don't care about blank nodes

    if child.name == 'key'
      # Save off the key, lowercasing and putting _ for space
      last_key = child.text.tr('A-Z','a-z').tr(' ','_')
    else
      # Use the key we saved
      hash[last_key] = child.text
    end
  end

  list << hash # push on to our list
  hash["track_id"] = hash["track_id"].to_i
  table_insert_hash db, "tracks", hash
  print "."
  counter += 1
  # for testing
  if counter > 100
    #puts "exiting during testing"
    #exit
  end
end
puts "#{counter} items"