4 This White Listing helper will html encode all tags and strip all attributes that aren't specifically allowed.
5 It also strips href/src tags with invalid protocols, like javascript: especially. It does its best to counter any
6 tricks that hackers may use, like throwing in unicode/ascii/hex values to get past the javascript: filters. Check out
7 the extensive test suite.
9 <%= white_list @article.body %>
11 You can add or remove tags/attributes if you want to customize it a bit.
15 WhiteListHelper.tags.merge %w(table td th)
19 WhiteListHelper.tags.delete 'div'
21 Change allowed attributes
23 WhiteListHelper.attributes.merge %w(id class style)
25 white_list accepts a block for custom tag escaping. Shown below is the default block that white_list uses if none is given.
26 The block is called for all bad tags, and every text node. node is an instance of HTML::Node (either HTML::Tag or HTML::Text).
27 bad is nil for text nodes inside good tags, or is the tag name of the bad tag.
29 <%= white_list(@article.body) { |node, bad| white_listed_bad_tags.include?(bad) ? nil : node.to_s.gsub(/</, '<') } %>