47 lines
1.1 KiB
Ruby
47 lines
1.1 KiB
Ruby
# frozen_string_literal: true
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# allow users to specify class attributes in their html
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# scrub invalid class names
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module OtwSanitize
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class UserClassSanitizer
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def self.transformer
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lambda do |env|
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# Check this node even if it is already safelisted.
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new(env[:node]).sanitized_node
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end
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end
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attr_reader :node
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# Takes a Nokogiri node
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def initialize(node)
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@node = node
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end
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# Update the class attribute with the sanitized value
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def sanitized_node
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return if user_classes.blank?
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node['class'] = sanitized_classes
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node
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end
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# Turn the class string into an array, select the valid values
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# then rejoin them
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def sanitized_classes
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user_classes.split(" ").
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select { |user_class| valid_class?(user_class) }.
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join(" ")
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end
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# let through alphanumeric class names with a dash/underscore
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def valid_class?(str)
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str =~ /^[a-zA-Z][\w\-]+$/
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end
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# If the element is something like <p class="apple banana">
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# then the value will be the string "apple banana"
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def user_classes
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node['class']
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end
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end
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end
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