# markdown is released under the BSD license
# Copyright 2007, 2008 The Python Markdown Project (v. 1.7 and later)
# Copyright 2004, 2005, 2006 Yuri Takhteyev (v. 0.2-1.6b)
# Copyright 2004 Manfred Stienstra (the original version)
#
# 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 <organization> 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 PYTHON MARKDOWN PROJECT ''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 ANY CONTRIBUTORS TO THE PYTHON MARKDOWN PROJECT
# 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.
"""
HeaderID Extension for Python-Markdown
======================================
Auto-generate id attributes for HTML headers.
Basic usage:
>>> import markdown
>>> text = "# Some Header #"
>>> md = markdown.markdown(text, ['headerid'])
>>> print md
<h1 id="some-header">Some Header</h1>
All header IDs are unique:
>>> text = '''
... #Header
... #Header
... #Header'''
>>> md = markdown.markdown(text, ['headerid'])
>>> print md
<h1 id="header">Header</h1>
<h1 id="header_1">Header</h1>
<h1 id="header_2">Header</h1>
To fit within a html template's hierarchy, set the header base level:
>>> text = '''
... #Some Header
... ## Next Level'''
>>> md = markdown.markdown(text, ['headerid(level=3)'])
>>> print md
<h3 id="some-header">Some Header</h3>
<h4 id="next-level">Next Level</h4>
Works with inline markup.
>>> text = '#Some *Header* with [markup](http://example.com).'
>>> md = markdown.markdown(text, ['headerid'])
>>> print md
<h1 id="some-header-with-markup">Some <em>Header</em> with <a href="http://example.com">markup</a>.</h1>
Turn off auto generated IDs:
>>> text = '''
... # Some Header
... # Another Header'''
>>> md = markdown.markdown(text, ['headerid(forceid=False)'])
>>> print md
<h1>Some Header</h1>
<h1>Another Header</h1>
Use with MetaData extension:
>>> text = '''header_level: 2
... header_forceid: Off
...
... # A Header'''
>>> md = markdown.markdown(text, ['headerid', 'meta'])
>>> print md
<h2>A Header</h2>
Copyright 2007-2011 [Waylan Limberg](http://achinghead.com/).
Project website: <http://packages.python.org/Markdown/extensions/header_id.html>
Contact: markdown@freewisdom.org
License: BSD (see ../docs/LICENSE for details)
Dependencies:
* [Python 2.3+](http://python.org)
* [Markdown 2.0+](http://packages.python.org/Markdown/)
"""
from __future__ import absolute_import
from __future__ import unicode_literals
from . import Extension
from ..treeprocessors import Treeprocessor
import re
import logging
import unicodedata
logger = logging.getLogger('MARKDOWN')
IDCOUNT_RE = re.compile(r'^(.*)_([0-9]+)$')
def slugify(value, separator):
""" Slugify a string, to make it URL friendly. """
value = unicodedata.normalize('NFKD', value).encode('ascii', 'ignore')
value = re.sub('[^\w\s-]', '', value.decode('ascii')).strip().lower()
return re.sub('[%s\s]+' % separator, separator, value)
def unique(id, ids):
""" Ensure id is unique in set of ids. Append '_1', '_2'... if not """
while id in ids or not id:
m = IDCOUNT_RE.match(id)
if m:
id = '%s_%d'% (m.group(1), int(m.group(2))+1)
else:
id = '%s_%d'% (id, 1)
ids.add(id)
return id
def itertext(elem):
""" Loop through all children and return text only.
Reimplements method of same name added to ElementTree in Python 2.7
"""
if elem.text:
yield elem.text
for e in elem:
for s in itertext(e):
yield s
if e.tail:
yield e.tail
class HeaderIdTreeprocessor(Treeprocessor):
""" Assign IDs to headers. """
IDs = set()
def run(self, doc):
start_level, force_id = self._get_meta()
slugify = self.config['slugify']
sep = self.config['separator']
for elem in doc.getiterator():
if elem.tag in ['h1', 'h2', 'h3', 'h4', 'h5', 'h6']:
if force_id:
if "id" in elem.attrib:
id = elem.get('id')
else:
id = slugify(''.join(itertext(elem)), sep)
elem.set('id', unique(id, self.IDs))
if start_level:
level = int(elem.tag[-1]) + start_level
if level > 6:
level = 6
elem.tag = 'h%d' % level
def _get_meta(self):
""" Return meta data suported by this ext as a tuple """
level = int(self.config['level']) - 1
force = self._str2bool(self.config['forceid'])
if hasattr(self.md, 'Meta'):
if 'header_level' in self.md.Meta:
level = int(self.md.Meta['header_level'][0]) - 1
if 'header_forceid' in self.md.Meta:
force = self._str2bool(self.md.Meta['header_forceid'][0])
return level, force
def _str2bool(self, s, default=False):
""" Convert a string to a booleen value. """
s = str(s)
if s.lower() in ['0', 'f', 'false', 'off', 'no', 'n']:
return False
elif s.lower() in ['1', 't', 'true', 'on', 'yes', 'y']:
return True
return default
class HeaderIdExtension(Extension):
def __init__(self, configs):
# set defaults
self.config = {
'level' : ['1', 'Base level for headers.'],
'forceid' : ['True', 'Force all headers to have an id.'],
'separator' : ['-', 'Word separator.'],
'slugify' : [slugify, 'Callable to generate anchors'],
}
for key, value in configs:
self.setConfig(key, value)
def extendMarkdown(self, md, md_globals):
md.registerExtension(self)
self.processor = HeaderIdTreeprocessor()
self.processor.md = md
self.processor.config = self.getConfigs()
if 'attr_list' in md.treeprocessors.keys():
# insert after attr_list treeprocessor
md.treeprocessors.add('headerid', self.processor, '>attr_list')
else:
# insert after 'prettify' treeprocessor.
md.treeprocessors.add('headerid', self.processor, '>prettify')
def reset(self):
self.processor.IDs = set()
def makeExtension(configs=None):
return HeaderIdExtension(configs=configs)