Bizarre field switch between cli and file output in Ruby - ruby

Question

I'm having such an strange issue with an ruby script which i'm working with... in this script i parse an iTunes Library xml file and form objects for Artists, Albums and Tracks. In my Album class, i have two numeric field, YEAR and TRACK_COUNT.
My script parses correctly the two fields, let's say, for example, the output of it:
#<Album:0x007f59b1472a18 #compilation=false, #title="Straight Out Of Hell", #year=2013, #track_count=13, #trackList=[], #coverList=[]>
when i output this same object to file, it get crippled, transforming to this, here in json format:
{"compilation":false,"title":"Straight Out Of Hell","year":13,"track_count":13,"trackList":[],"coverList":[]}]
as you can see, the field YEAR get overwritten with the value in TRACK_COUNT field... i'm getting crazy with this, as i don't do any change to this field between these outputs!
UPDATE
As asked by #Amadan...
http://pastebin.com/1FUuvaCr Biblioteca.xml (EXCERPT)
http://pastebin.com/F8wgu6bz Track.rb
http://pastebin.com/3qhd4TRU Song.rb
http://pastebin.com/RNf5S7AZ dependencies.rb
http://pastebin.com/haXPpJgN Cover.rb
http://pastebin.com/1JYtT1nn Artist.rb
http://pastebin.com/qsgLsAJa Album.rb
http://pastebin.com/eiUAMfwR app.rb (MAIN SCRIPT)

Answer 1

This is happening because your source file is not as clean as you believe it to be. In some albums in the source XML, "Track Count" and "Year" are appearing on the same line, without a recognized line break between them. So you might have a line like this:
<key>Track Count</key><integer>12</integer><key>Year</key><integer>2006</integer>
When your if-else-if ladder asks if "track count" appears in the line, it does, so you're grabbing the first <integer>something</integer> match on the line. This works fine. But when you try to extract the year out of this line, you're again asking for the first <integer> on the line, which is the Track Count.
The bigger problem is that you're attempting to parse an XML file line-by-line, and that's not how they're meant to be read. Install the nokogiri gem and call this:
data = Nokogiri::XML('Biblioteca.xml')
Now you can get to any information contained in the document. The official tutorials on user Nokogiri are here: http://www.nokogiri.org/tutorials/
Use this method to parse your file:
def parse filename
xml = Nokogiri::XML(filename)
songs = xml.css('dict key').select{|key| key.text =~ /^[0-9]{4}$/}
songs.map do |song|
info = {}
song.next_element.css('key').each do |attribute|
info[attribute.text] = attribute.next_element.text
end
info
end
end
This will create a list of song hashes. Here are some examples for how to use it:
# load the two songs in your example file
songs = parse('Biblioteca.xml')
# Get the year of the first song
songs[0]['Year'] #=> 2006
# Get the Track Count of the second song's album
songs[1]['Track Count'] #=> 12
# Get the Name of the second song
songs[1]['Name'] #=> 'Baby Come On'
# Get the Album name of the second song
songs[1]['Album'] #=> 'When Your Heart Stops Beating'
From here, you can easily put info into your song objects. Let me know if you have any more questions.

Answer 2

I've found a library for iTunes dodgy plist xml standart... Nokogiri-plist... working fine now :D