Copyright (c) 2014, David Kitchen <david@buro9.com> All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. * Neither the name of the organisation (Microcosm) nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

package bluemonday

import (
	
)
StrictPolicy returns an empty policy, which will effectively strip all HTML elements and their attributes from a document.
func () *Policy {
	return NewPolicy()
}
StripTagsPolicy is DEPRECATED. Use StrictPolicy instead.
func () *Policy {
	return StrictPolicy()
}
UGCPolicy returns a policy aimed at user generated content that is a result of HTML WYSIWYG tools and Markdown conversions. This is expected to be a fairly rich document where as much markup as possible should be retained. Markdown permits raw HTML so we are basically providing a policy to sanitise HTML5 documents safely but with the least intrusion on the formatting expectations of the user.
func () *Policy {

	 := NewPolicy()
///////////////////// Global attributes // /////////////////////
"class" is not permitted as we are not allowing users to style their own content

	.AllowStandardAttributes()
//////////////////////////// Global URL format policy // ////////////////////////////

	.AllowStandardURLs()
////////////////////////////// Declarations and structure // //////////////////////////////
"xml" "xslt" "DOCTYPE" "html" "head" are not permitted as we are expecting user generated content to be a fragment of HTML and not a full document.
//////////////////////// Sectioning root tags // ////////////////////////
"article" and "aside" are permitted and takes no attributes
	.AllowElements("article", "aside")
"body" is not permitted as we are expecting user generated content to be a fragment of HTML and not a full document.
"details" is permitted, including the "open" attribute which can either be blank or the value "open".
	.AllowAttrs(
		"open",
	).Matching(regexp.MustCompile(`(?i)^(|open)$`)).OnElements("details")
"fieldset" is not permitted as we are not allowing forms to be created.
"figure" is permitted and takes no attributes
	.AllowElements("figure")
"nav" is not permitted as it is assumed that the site (and not the user) has defined navigation elements
"section" is permitted and takes no attributes
	.AllowElements("section")
"summary" is permitted and takes no attributes
	.AllowElements("summary")
//////////////////////// Headings and footers // ////////////////////////
"footer" is not permitted as we expect user content to be a fragment and not structural to this extent
"h1" through "h6" are permitted and take no attributes
	.AllowElements("h1", "h2", "h3", "h4", "h5", "h6")
"header" is not permitted as we expect user content to be a fragment and not structural to this extent
"hgroup" is permitted and takes no attributes
	.AllowElements("hgroup")
/////////////////////////////////// Content grouping and separating // ///////////////////////////////////
"blockquote" is permitted, including the "cite" attribute which must be a standard URL.
	.AllowAttrs("cite").OnElements("blockquote")
"br" "div" "hr" "p" "span" "wbr" are permitted and take no attributes
	.AllowElements("br", "div", "hr", "p", "span", "wbr")
///////// Links // /////////
"a" is permitted
	.AllowAttrs("href").OnElements("a")
"area" is permitted along with the attributes that map image maps work
	.AllowAttrs("name").Matching(
		regexp.MustCompile(`^([\p{L}\p{N}_-]+)$`),
	).OnElements("map")
	.AllowAttrs("alt").Matching(Paragraph).OnElements("area")
	.AllowAttrs("coords").Matching(
		regexp.MustCompile(`^([0-9]+,)+[0-9]+$`),
	).OnElements("area")
	.AllowAttrs("href").OnElements("area")
	.AllowAttrs("rel").Matching(SpaceSeparatedTokens).OnElements("area")
	.AllowAttrs("shape").Matching(
		regexp.MustCompile(`(?i)^(default|circle|rect|poly)$`),
	).OnElements("area")
	.AllowAttrs("usemap").Matching(
		regexp.MustCompile(`(?i)^#[\p{L}\p{N}_-]+$`),
	).OnElements("img")
"link" is not permitted
/////////////////// Phrase elements // ///////////////////
The following are all inline phrasing elements
	.AllowElements("abbr", "acronym", "cite", "code", "dfn", "em",
		"figcaption", "mark", "s", "samp", "strong", "sub", "sup", "var")
"q" is permitted and "cite" is a URL and handled by URL policies
	.AllowAttrs("cite").OnElements("q")
"time" is permitted
	.AllowAttrs("datetime").Matching(ISO8601).OnElements("time")
////////////////// Style elements // //////////////////
block and inline elements that impart no semantic meaning but style the document
	.AllowElements("b", "i", "pre", "small", "strike", "tt", "u")
"style" is not permitted as we are not yet sanitising CSS and it is an XSS attack vector
//////////////////// HTML5 Formatting // ////////////////////
"bdi" "bdo" are permitted
	.AllowAttrs("dir").Matching(Direction).OnElements("bdi", "bdo")
"rp" "rt" "ruby" are permitted
	.AllowElements("rp", "rt", "ruby")
///////////////////////// HTML5 Change tracking // /////////////////////////
"del" "ins" are permitted
	.AllowAttrs("cite").Matching(Paragraph).OnElements("del", "ins")
	.AllowAttrs("datetime").Matching(ISO8601).OnElements("del", "ins")
///////// Lists // /////////

	.AllowLists()
////////// Tables // //////////

	.AllowTables()
///////// Forms // /////////
By and large, forms are not permitted. However there are some form elements that can be used to present data, and we do permit those "button" "fieldset" "input" "keygen" "label" "output" "select" "datalist" "textarea" "optgroup" "option" are all not permitted
"meter" is permitted
	.AllowAttrs(
		"value",
		"min",
		"max",
		"low",
		"high",
		"optimum",
	).Matching(Number).OnElements("meter")
"progress" is permitted
	.AllowAttrs("value", "max").Matching(Number).OnElements("progress")
//////////////////// Embedded content // ////////////////////
Vast majority not permitted "audio" "canvas" "embed" "iframe" "object" "param" "source" "svg" "track" "video" are all not permitted

	.AllowImages()

	return