module ActionView::Helpers::SanitizeHelper
The SanitizeHelper
module provides a set of methods for scrubbing text of undesired HTML elements. These helper methods extend Action View making them callable within your template files.
Public Instance Methods
Sanitizes HTML input, stripping all but known-safe tags and attributes.
It also strips href/src attributes with unsafe protocols like javascript:
, while also protecting against attempts to use Unicode, ASCII, and hex character references to work around these protocol filters. All special characters will be escaped.
The default sanitizer is Rails::Html::SafeListSanitizer. See Rails HTML Sanitizers for more information.
Custom sanitization rules can also be provided.
Please note that sanitizing user-provided text does not guarantee that the resulting markup is valid or even well-formed.
Options¶ ↑
-
:tags
- An array of allowed tags. -
:attributes
- An array of allowed attributes. -
:scrubber
- A Rails::Html scrubber or Loofah::Scrubber object that defines custom sanitization rules. A custom scrubber takes precedence over custom tags and attributes.
Examples¶ ↑
Normal use:
<%= sanitize @comment.body %>
Providing custom lists of permitted tags and attributes:
<%= sanitize @comment.body, tags: %w(strong em a), attributes: %w(href) %>
Providing a custom Rails::Html scrubber:
class CommentScrubber < Rails::Html::PermitScrubber def initialize super self.tags = %w( form script comment blockquote ) self.attributes = %w( style ) end def skip_node?(node) node.text? end end <%= sanitize @comment.body, scrubber: CommentScrubber.new %>
See Rails HTML Sanitizer for documentation about Rails::Html scrubbers.
Providing a custom Loofah::Scrubber:
scrubber = Loofah::Scrubber.new do |node| node.remove if node.name == 'script' end <%= sanitize @comment.body, scrubber: scrubber %>
See Loofah’s documentation for more information about defining custom Loofah::Scrubber objects.
To set the default allowed tags or attributes across your application:
# In config/application.rb config.action_view.sanitized_allowed_tags = ['strong', 'em', 'a'] config.action_view.sanitized_allowed_attributes = ['href', 'title']
# File lib/action_view/helpers/sanitize_helper.rb, line 81 def sanitize(html, options = {}) self.class.safe_list_sanitizer.sanitize(html, options)&.html_safe end
Sanitizes a block of CSS code. Used by sanitize
when it comes across a style attribute.
# File lib/action_view/helpers/sanitize_helper.rb, line 86 def sanitize_css(style) self.class.safe_list_sanitizer.sanitize_css(style) end
Strips all link tags from html
leaving just the link text.
strip_links('<a href="http://www.rubyonrails.org">Ruby on Rails</a>') # => Ruby on Rails strip_links('Please e-mail me at <a href="mailto:me@email.com">me@email.com</a>.') # => Please e-mail me at me@email.com. strip_links('Blog: <a href="http://www.myblog.com/" class="nav" target=\"_blank\">Visit</a>.') # => Blog: Visit. strip_links('<<a href="https://example.org">malformed & link</a>') # => <malformed & link
# File lib/action_view/helpers/sanitize_helper.rb, line 120 def strip_links(html) self.class.link_sanitizer.sanitize(html) end