Strip style attributes with nokogiri

keepitterron picture keepitterron · May 23, 2011 · Viewed 11.8k times · Source

I'm scrapling an html page with nokogiri and i want to strip out all style attributes.
How can I achieve this? (i'm not using rails so i can't use it's sanitize method and i don't want to use sanitize gem 'cause i want to blacklist remove not whitelist)

html = open(url)
doc = Nokogiri::HTML(html.read)
doc.css('.post').each do |post|
puts post.to_s
end

=> <p><span style="font-size: x-large">bla bla <a href="http://torrentfreak.com/netflix-is-killing-bittorrent-in-the-us-110427/">statistica</a> blabla</span></p>

I want it to be

=> <p><span>bla bla <a href="http://torrentfreak.com/netflix-is-killing-bittorrent-in-the-us-110427/">statistica</a> blabla</span></p>

Answer

Phrogz picture Phrogz · May 24, 2011
require 'nokogiri'

html = '<p class="post"><span style="font-size: x-large">bla bla</span></p>'
doc = Nokogiri::HTML(html)
doc.xpath('//@style').remove
puts doc.css('.post')
#=> <p class="post"><span>bla bla</span></p>

Edited to show that you can just call NodeSet#remove instead of having to use .each(&:remove).

Note that if you have a DocumentFragment instead of a Document, Nokogiri has a longstanding bug where searching from a fragment does not work as you would expect. The workaround is to use:

doc.xpath('@style|.//@style').remove