How to access attributes using Nokogiri
- by Liz
I have a simple task of accessing the values of some attributes. Below is a simple script that uses Nokogiri::XML::Builder to create a simple xml doc.
require 'nokogiri'
builder = Nokogiri::XML::Builder.new(:encoding => 'UTF-8') do |xml|
xml.Placement(:messageId => "392847-039820-938777", :system => "MOD", :version => "2.0") {
xml.objects {
xml.object(:myattribute => "99", :anotherattrib => "333")
xml.nextobject_ '9387toot'
xml.Entertainment "Last Man Standing"
}
}
end
puts builder.to_xml
puts builder.root.attributes["messageId"]
The results are below:
<?xml version="1.0" encoding="UTF-8"?>
<Placement messageId="392847-039820-938777" version="2.0" system="MOD">
<objects>
<object anotherattrib="333" myattribute="99"/>
<nextobject>9387toot</nextobject>
<Entertainment>Last Man Standing</Entertainment>
</objects>
</Placement>
C:/Ruby/lib/ruby/gems/1.8/gems/nokogiri-1.4.2-x86-mingw32/lib/nokogiri/xml/document.rb:178:in `add_child': Document already has a root node (RuntimeError)
from C:/Ruby/lib/ruby/gems/1.8/gems/nokogiri-1.4.2-x86-mingw32/lib/nokogiri/xml/node.rb:455:in `parent='
from C:/Ruby/lib/ruby/gems/1.8/gems/nokogiri-1.4.2-x86-mingw32/lib/nokogiri/xml/builder.rb:358:in `insert'
from C:/Ruby/lib/ruby/gems/1.8/gems/nokogiri-1.4.2-x86-mingw32/lib/nokogiri/xml/builder.rb:350:in `method_missing'
from C:/Documents and Settings/etrojan/workspace/Lads/tryXPATH2.rb:15
The xml that is generated looks fine. However, my attempts to access attributes cause an error to be generated, "Document already has a root node". I don't understand why a puts statement would cause this error. Any suggestions would be greatly appreciated.