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.
406 lines
15 KiB
406 lines
15 KiB
"""
|
|
Python Markdown
|
|
|
|
A Python implementation of John Gruber's Markdown.
|
|
|
|
Documentation: https://python-markdown.github.io/
|
|
GitHub: https://github.com/Python-Markdown/markdown/
|
|
PyPI: https://pypi.org/project/Markdown/
|
|
|
|
Started by Manfred Stienstra (http://www.dwerg.net/).
|
|
Maintained for a few years by Yuri Takhteyev (http://www.freewisdom.org).
|
|
Currently maintained by Waylan Limberg (https://github.com/waylan),
|
|
Dmitry Shachnev (https://github.com/mitya57) and Isaac Muse (https://github.com/facelessuser).
|
|
|
|
Copyright 2007-2018 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)
|
|
|
|
License: BSD (see LICENSE.md for details).
|
|
"""
|
|
|
|
import codecs
|
|
import sys
|
|
import logging
|
|
import importlib
|
|
from . import util
|
|
from .preprocessors import build_preprocessors
|
|
from .blockprocessors import build_block_parser
|
|
from .treeprocessors import build_treeprocessors
|
|
from .inlinepatterns import build_inlinepatterns
|
|
from .postprocessors import build_postprocessors
|
|
from .extensions import Extension
|
|
from .serializers import to_html_string, to_xhtml_string
|
|
|
|
__all__ = ['Markdown', 'markdown', 'markdownFromFile']
|
|
|
|
|
|
logger = logging.getLogger('MARKDOWN')
|
|
|
|
|
|
class Markdown:
|
|
"""Convert Markdown to HTML."""
|
|
|
|
doc_tag = "div" # Element used to wrap document - later removed
|
|
|
|
output_formats = {
|
|
'html': to_html_string,
|
|
'xhtml': to_xhtml_string,
|
|
}
|
|
|
|
def __init__(self, **kwargs):
|
|
"""
|
|
Creates a new Markdown instance.
|
|
|
|
Keyword arguments:
|
|
|
|
* extensions: A list of extensions.
|
|
If an item is an instance of a subclass of `markdown.extension.Extension`, the instance will be used
|
|
as-is. If an item is of type string, first an entry point will be loaded. If that fails, the string is
|
|
assumed to use Python dot notation (`path.to.module:ClassName`) to load a markdown.Extension subclass. If
|
|
no class is specified, then a `makeExtension` function is called within the specified module.
|
|
* extension_configs: Configuration settings for extensions.
|
|
* output_format: Format of output. Supported formats are:
|
|
* "xhtml": Outputs XHTML style tags. Default.
|
|
* "html": Outputs HTML style tags.
|
|
* tab_length: Length of tabs in the source. Default: 4
|
|
|
|
"""
|
|
|
|
self.tab_length = kwargs.get('tab_length', 4)
|
|
|
|
self.ESCAPED_CHARS = ['\\', '`', '*', '_', '{', '}', '[', ']',
|
|
'(', ')', '>', '#', '+', '-', '.', '!']
|
|
|
|
self.block_level_elements = [
|
|
# Elements which are invalid to wrap in a `<p>` tag.
|
|
# See https://w3c.github.io/html/grouping-content.html#the-p-element
|
|
'address', 'article', 'aside', 'blockquote', 'details', 'div', 'dl',
|
|
'fieldset', 'figcaption', 'figure', 'footer', 'form', 'h1', 'h2', 'h3',
|
|
'h4', 'h5', 'h6', 'header', 'hr', 'main', 'menu', 'nav', 'ol', 'p', 'pre',
|
|
'section', 'table', 'ul',
|
|
# Other elements which Markdown should not be mucking up the contents of.
|
|
'canvas', 'dd', 'dt', 'group', 'iframe', 'li', 'math', 'noscript', 'output',
|
|
'progress', 'script', 'style', 'tbody', 'td', 'th', 'thead', 'tr', 'video'
|
|
]
|
|
|
|
self.registeredExtensions = []
|
|
self.docType = ""
|
|
self.stripTopLevelTags = True
|
|
|
|
self.build_parser()
|
|
|
|
self.references = {}
|
|
self.htmlStash = util.HtmlStash()
|
|
self.registerExtensions(extensions=kwargs.get('extensions', []),
|
|
configs=kwargs.get('extension_configs', {}))
|
|
self.set_output_format(kwargs.get('output_format', 'xhtml'))
|
|
self.reset()
|
|
|
|
def build_parser(self):
|
|
""" Build the parser from the various parts. """
|
|
self.preprocessors = build_preprocessors(self)
|
|
self.parser = build_block_parser(self)
|
|
self.inlinePatterns = build_inlinepatterns(self)
|
|
self.treeprocessors = build_treeprocessors(self)
|
|
self.postprocessors = build_postprocessors(self)
|
|
return self
|
|
|
|
def registerExtensions(self, extensions, configs):
|
|
"""
|
|
Register extensions with this instance of Markdown.
|
|
|
|
Keyword arguments:
|
|
|
|
* extensions: A list of extensions, which can either
|
|
be strings or objects.
|
|
* configs: A dictionary mapping extension names to config options.
|
|
|
|
"""
|
|
for ext in extensions:
|
|
if isinstance(ext, str):
|
|
ext = self.build_extension(ext, configs.get(ext, {}))
|
|
if isinstance(ext, Extension):
|
|
ext._extendMarkdown(self)
|
|
logger.debug(
|
|
'Successfully loaded extension "%s.%s".'
|
|
% (ext.__class__.__module__, ext.__class__.__name__)
|
|
)
|
|
elif ext is not None:
|
|
raise TypeError(
|
|
'Extension "{}.{}" must be of type: "{}.{}"'.format(
|
|
ext.__class__.__module__, ext.__class__.__name__,
|
|
Extension.__module__, Extension.__name__
|
|
)
|
|
)
|
|
return self
|
|
|
|
def build_extension(self, ext_name, configs):
|
|
"""
|
|
Build extension from a string name, then return an instance.
|
|
|
|
First attempt to load an entry point. The string name must be registered as an entry point in the
|
|
`markdown.extensions` group which points to a subclass of the `markdown.extensions.Extension` class.
|
|
If multiple distributions have registered the same name, the first one found is returned.
|
|
|
|
If no entry point is found, assume dot notation (`path.to.module:ClassName`). Load the specified class and
|
|
return an instance. If no class is specified, import the module and call a `makeExtension` function and return
|
|
the Extension instance returned by that function.
|
|
"""
|
|
configs = dict(configs)
|
|
|
|
entry_points = [ep for ep in util.INSTALLED_EXTENSIONS if ep.name == ext_name]
|
|
if entry_points:
|
|
ext = entry_points[0].load()
|
|
return ext(**configs)
|
|
|
|
# Get class name (if provided): `path.to.module:ClassName`
|
|
ext_name, class_name = ext_name.split(':', 1) if ':' in ext_name else (ext_name, '')
|
|
|
|
try:
|
|
module = importlib.import_module(ext_name)
|
|
logger.debug(
|
|
'Successfully imported extension module "%s".' % ext_name
|
|
)
|
|
except ImportError as e:
|
|
message = 'Failed loading extension "%s".' % ext_name
|
|
e.args = (message,) + e.args[1:]
|
|
raise
|
|
|
|
if class_name:
|
|
# Load given class name from module.
|
|
return getattr(module, class_name)(**configs)
|
|
else:
|
|
# Expect makeExtension() function to return a class.
|
|
try:
|
|
return module.makeExtension(**configs)
|
|
except AttributeError as e:
|
|
message = e.args[0]
|
|
message = "Failed to initiate extension " \
|
|
"'%s': %s" % (ext_name, message)
|
|
e.args = (message,) + e.args[1:]
|
|
raise
|
|
|
|
def registerExtension(self, extension):
|
|
""" This gets called by the extension """
|
|
self.registeredExtensions.append(extension)
|
|
return self
|
|
|
|
def reset(self):
|
|
"""
|
|
Resets all state variables so that we can start with a new text.
|
|
"""
|
|
self.htmlStash.reset()
|
|
self.references.clear()
|
|
|
|
for extension in self.registeredExtensions:
|
|
if hasattr(extension, 'reset'):
|
|
extension.reset()
|
|
|
|
return self
|
|
|
|
def set_output_format(self, format):
|
|
""" Set the output format for the class instance. """
|
|
self.output_format = format.lower().rstrip('145') # ignore num
|
|
try:
|
|
self.serializer = self.output_formats[self.output_format]
|
|
except KeyError as e:
|
|
valid_formats = list(self.output_formats.keys())
|
|
valid_formats.sort()
|
|
message = 'Invalid Output Format: "%s". Use one of %s.' \
|
|
% (self.output_format,
|
|
'"' + '", "'.join(valid_formats) + '"')
|
|
e.args = (message,) + e.args[1:]
|
|
raise
|
|
return self
|
|
|
|
def is_block_level(self, tag):
|
|
"""Check if the tag is a block level HTML tag."""
|
|
if isinstance(tag, str):
|
|
return tag.lower().rstrip('/') in self.block_level_elements
|
|
# Some ElementTree tags are not strings, so return False.
|
|
return False
|
|
|
|
def convert(self, source):
|
|
"""
|
|
Convert markdown to serialized XHTML or HTML.
|
|
|
|
Keyword arguments:
|
|
|
|
* source: Source text as a Unicode string.
|
|
|
|
Markdown processing takes place in five steps:
|
|
|
|
1. A bunch of "preprocessors" munge the input text.
|
|
2. BlockParser() parses the high-level structural elements of the
|
|
pre-processed text into an ElementTree.
|
|
3. A bunch of "treeprocessors" are run against the ElementTree. One
|
|
such treeprocessor runs InlinePatterns against the ElementTree,
|
|
detecting inline markup.
|
|
4. Some post-processors are run against the text after the ElementTree
|
|
has been serialized into text.
|
|
5. The output is written to a string.
|
|
|
|
"""
|
|
|
|
# Fixup the source text
|
|
if not source.strip():
|
|
return '' # a blank unicode string
|
|
|
|
try:
|
|
source = str(source)
|
|
except UnicodeDecodeError as e: # pragma: no cover
|
|
# Customise error message while maintaining original trackback
|
|
e.reason += '. -- Note: Markdown only accepts unicode input!'
|
|
raise
|
|
|
|
# Split into lines and run the line preprocessors.
|
|
self.lines = source.split("\n")
|
|
for prep in self.preprocessors:
|
|
self.lines = prep.run(self.lines)
|
|
|
|
# Parse the high-level elements.
|
|
root = self.parser.parseDocument(self.lines).getroot()
|
|
|
|
# Run the tree-processors
|
|
for treeprocessor in self.treeprocessors:
|
|
newRoot = treeprocessor.run(root)
|
|
if newRoot is not None:
|
|
root = newRoot
|
|
|
|
# Serialize _properly_. Strip top-level tags.
|
|
output = self.serializer(root)
|
|
if self.stripTopLevelTags:
|
|
try:
|
|
start = output.index(
|
|
'<%s>' % self.doc_tag) + len(self.doc_tag) + 2
|
|
end = output.rindex('</%s>' % self.doc_tag)
|
|
output = output[start:end].strip()
|
|
except ValueError: # pragma: no cover
|
|
if output.strip().endswith('<%s />' % self.doc_tag):
|
|
# We have an empty document
|
|
output = ''
|
|
else:
|
|
# We have a serious problem
|
|
raise ValueError('Markdown failed to strip top-level '
|
|
'tags. Document=%r' % output.strip())
|
|
|
|
# Run the text post-processors
|
|
for pp in self.postprocessors:
|
|
output = pp.run(output)
|
|
|
|
return output.strip()
|
|
|
|
def convertFile(self, input=None, output=None, encoding=None):
|
|
"""Converts a markdown file and returns the HTML as a unicode string.
|
|
|
|
Decodes the file using the provided encoding (defaults to utf-8),
|
|
passes the file content to markdown, and outputs the html to either
|
|
the provided stream or the file with provided name, using the same
|
|
encoding as the source file. The 'xmlcharrefreplace' error handler is
|
|
used when encoding the output.
|
|
|
|
**Note:** This is the only place that decoding and encoding of unicode
|
|
takes place in Python-Markdown. (All other code is unicode-in /
|
|
unicode-out.)
|
|
|
|
Keyword arguments:
|
|
|
|
* input: File object or path. Reads from stdin if `None`.
|
|
* output: File object or path. Writes to stdout if `None`.
|
|
* encoding: Encoding of input and output files. Defaults to utf-8.
|
|
|
|
"""
|
|
|
|
encoding = encoding or "utf-8"
|
|
|
|
# Read the source
|
|
if input:
|
|
if isinstance(input, str):
|
|
input_file = codecs.open(input, mode="r", encoding=encoding)
|
|
else:
|
|
input_file = codecs.getreader(encoding)(input)
|
|
text = input_file.read()
|
|
input_file.close()
|
|
else:
|
|
text = sys.stdin.read()
|
|
if not isinstance(text, str): # pragma: no cover
|
|
text = text.decode(encoding)
|
|
|
|
text = text.lstrip('\ufeff') # remove the byte-order mark
|
|
|
|
# Convert
|
|
html = self.convert(text)
|
|
|
|
# Write to file or stdout
|
|
if output:
|
|
if isinstance(output, str):
|
|
output_file = codecs.open(output, "w",
|
|
encoding=encoding,
|
|
errors="xmlcharrefreplace")
|
|
output_file.write(html)
|
|
output_file.close()
|
|
else:
|
|
writer = codecs.getwriter(encoding)
|
|
output_file = writer(output, errors="xmlcharrefreplace")
|
|
output_file.write(html)
|
|
# Don't close here. User may want to write more.
|
|
else:
|
|
# Encode manually and write bytes to stdout.
|
|
html = html.encode(encoding, "xmlcharrefreplace")
|
|
try:
|
|
# Write bytes directly to buffer (Python 3).
|
|
sys.stdout.buffer.write(html)
|
|
except AttributeError: # pragma: no cover
|
|
# Probably Python 2, which works with bytes by default.
|
|
sys.stdout.write(html)
|
|
|
|
return self
|
|
|
|
|
|
"""
|
|
EXPORTED FUNCTIONS
|
|
=============================================================================
|
|
|
|
Those are the two functions we really mean to export: markdown() and
|
|
markdownFromFile().
|
|
"""
|
|
|
|
|
|
def markdown(text, **kwargs):
|
|
"""Convert a markdown string to HTML and return HTML as a unicode string.
|
|
|
|
This is a shortcut function for `Markdown` class to cover the most
|
|
basic use case. It initializes an instance of Markdown, loads the
|
|
necessary extensions and runs the parser on the given text.
|
|
|
|
Keyword arguments:
|
|
|
|
* text: Markdown formatted text as Unicode or ASCII string.
|
|
* Any arguments accepted by the Markdown class.
|
|
|
|
Returns: An HTML document as a string.
|
|
|
|
"""
|
|
md = Markdown(**kwargs)
|
|
return md.convert(text)
|
|
|
|
|
|
def markdownFromFile(**kwargs):
|
|
"""Read markdown code from a file and write it to a file or a stream.
|
|
|
|
This is a shortcut function which initializes an instance of Markdown,
|
|
and calls the convertFile method rather than convert.
|
|
|
|
Keyword arguments:
|
|
|
|
* input: a file name or readable object.
|
|
* output: a file name or writable object.
|
|
* encoding: Encoding of input and output.
|
|
* Any arguments accepted by the Markdown class.
|
|
|
|
"""
|
|
md = Markdown(**kwargs)
|
|
md.convertFile(kwargs.get('input', None),
|
|
kwargs.get('output', None),
|
|
kwargs.get('encoding', None))
|
|
|