You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
107 lines
3.0 KiB
107 lines
3.0 KiB
# -*- encoding: utf-8 -*-
|
|
|
|
from __future__ import unicode_literals
|
|
|
|
import pkg_resources
|
|
|
|
from distutils.version import LooseVersion as Version
|
|
|
|
HTML5LIB_VERSION = Version(pkg_resources.get_distribution("html5lib").version)
|
|
HTML5LIB_SIMPLETREE = Version("0.95")
|
|
|
|
import html5lib
|
|
from html5lib.sanitizer import HTMLSanitizer
|
|
from html5lib.serializer import HTMLSerializer
|
|
|
|
import misaka
|
|
|
|
|
|
def Sanitizer(elements, attributes):
|
|
|
|
class Inner(HTMLSanitizer):
|
|
|
|
# attributes found in Sundown's HTML serializer [1]
|
|
# except for <img> tag,
|
|
# because images are not generated anyways.
|
|
#
|
|
# [1] https://github.com/vmg/sundown/blob/master/html/html.c
|
|
allowed_elements = ["a", "p", "hr", "br", "ol", "ul", "li",
|
|
"pre", "code", "blockquote",
|
|
"del", "ins", "strong", "em",
|
|
"h1", "h2", "h3", "h4", "h5", "h6",
|
|
"table", "thead", "tbody", "th", "td"] + elements
|
|
|
|
# href for <a> and align for <table>
|
|
allowed_attributes = ["align", "href"] + attributes
|
|
|
|
# remove disallowed tokens from the output
|
|
def disallowed_token(self, token, token_type):
|
|
return None
|
|
|
|
return Inner
|
|
|
|
|
|
def sanitize(tokenizer, document):
|
|
|
|
parser = html5lib.HTMLParser(tokenizer=tokenizer)
|
|
domtree = parser.parseFragment(document)
|
|
|
|
if HTML5LIB_VERSION > HTML5LIB_SIMPLETREE:
|
|
builder = "etree"
|
|
|
|
for link in domtree.findall(".//{http://www.w3.org/1999/xhtml}a"):
|
|
if link.get('href', None):
|
|
link.set("rel", "nofollow noopener")
|
|
|
|
else:
|
|
builder = "simpletree"
|
|
|
|
stream = html5lib.treewalkers.getTreeWalker(builder)(domtree)
|
|
serializer = HTMLSerializer(
|
|
quote_attr_values=True, omit_optional_tags=False)
|
|
|
|
return serializer.render(stream)
|
|
|
|
|
|
def Markdown(extensions=("strikethrough", "superscript", "autolink",
|
|
"fenced-code")):
|
|
|
|
renderer = Unofficial()
|
|
md = misaka.Markdown(renderer, extensions=extensions)
|
|
|
|
def inner(text):
|
|
rv = md(text).rstrip("\n")
|
|
if rv.startswith("<p>") or rv.endswith("</p>"):
|
|
return rv
|
|
return "<p>" + rv + "</p>"
|
|
|
|
return inner
|
|
|
|
|
|
class Unofficial(misaka.HtmlRenderer):
|
|
"""A few modifications to process "common" Markdown.
|
|
|
|
For instance, fenced code blocks (~~~ or ```) are just wrapped in <code>
|
|
which does not preserve line breaks. If a language is given, it is added
|
|
to <code class="$lang">, compatible with Highlight.js.
|
|
"""
|
|
|
|
def blockcode(self, text, lang):
|
|
lang = ' class="{0}"'.format(lang) if lang else ''
|
|
return "<pre><code{1}>{0}</code></pre>\n".format(text, lang)
|
|
|
|
|
|
class Markup(object):
|
|
|
|
def __init__(self, conf):
|
|
|
|
parser = Markdown(conf.getlist("options"))
|
|
sanitizer = Sanitizer(
|
|
conf.getlist("allowed-elements"),
|
|
conf.getlist("allowed-attributes"))
|
|
|
|
self._render = lambda text: sanitize(sanitizer, parser(text))
|
|
|
|
def render(self, text):
|
|
return self._render(text)
|