creating large file xml in ruby

Solution 1

If speed is your main concern, I'd just use libxml-ruby directly:

$ time ruby test.rb real    0m7.352suser    0m5.867ssys     0m0.921s

The API is pretty straight forward:

require 'rubygems'require 'xml'doc = XML::Document.new()doc.root = XML::Node.new('root_node')root = doc.root500000.times do |k|  root << elem1 = XML::Node.new('products')  elem1 << elem2 = XML::Node.new('widget')  elem2['id'] = k.to_s  elem2['name'] = 'Awesome widget'enddoc.save('foo.xml', :indent => false, :encoding => XML::Encoding::UTF_8)

Using :indent => true doesn't make much difference in this case, but for more complex XML files it might.

$ time ruby test.rb #(with indent)real    0m7.395suser    0m6.050ssys     0m0.847s

Solution 2

Of course the fastest solution, and that doesn't build up on memory is just to write the XML manually but that will easily generate other sources of error like possibly invalid XML:

$ time ruby test.rb real    0m1.131suser    0m0.873ssys     0m0.126s

Here's the code:

f = File.open("foo.xml", "w")f.puts('<doc>')500000.times do |k|  f.puts "<product><widget id=\"#{k}\" name=\"Awesome widget\" /></product>"endf.puts('</doc>')f.close