` element containing the matching text. """
def __init__ (self, pattern):
Pattern.__init__(self, pattern)
self.tag = "code"
def handleMatch(self, m):
el = etree.Element(self.tag)
el.text = AtomicString(m.group(3).strip())
return el
class DoubleTagPattern (SimpleTagPattern):
"""Return a ElementTree element nested in tag2 nested in tag1.
Useful for strong emphasis etc.
"""
def handleMatch(self, m):
tag1, tag2 = self.tag.split(",")
el1 = etree.Element(tag1)
el2 = etree.SubElement(el1, tag2)
el2.text = m.group(3)
return el1
class HtmlPattern (Pattern):
""" Store raw inline html and return a placeholder. """
def handleMatch (self, m):
rawhtml = m.group(2)
inline = True
place_holder = self.stash.store(rawhtml)
return place_holder
class LinkPattern (Pattern):
""" Return a link element from the given match. """
def handleMatch(self, m):
el = etree.Element("a")
el.text = m.group(2)
title = m.group(11)
href = m.group(9)
if href:
if href[0] == "<":
href = href[1:-1]
el.set("href", self.sanitize_url(href.strip()))
else:
el.set("href", "")
if title:
title = dequote(title) #.replace('"', """)
el.set("title", title)
return el
def sanitize_url(self, url):
"""
Sanitize a url against xss attacks in "safe_mode".
Rather than specifically blacklisting `javascript:alert("XSS")` and all
its aliases (see ), we whitelist known
safe url formats. Most urls contain a network location, however some
are known not to (i.e.: mailto links). Script urls do not contain a
location. Additionally, for `javascript:...`, the scheme would be
"javascript" but some aliases will appear to `urlparse()` to have no
scheme. On top of that relative links (i.e.: "foo/bar.html") have no
scheme. Therefore we must check "path", "parameters", "query" and
"fragment" for any literal colons. We don't check "scheme" for colons
because it *should* never have any and "netloc" must allow the form:
`username:password@host:port`.
"""
locless_schemes = ['', 'mailto', 'news']
scheme, netloc, path, params, query, fragment = url = urlparse(url)
safe_url = False
if netloc != '' or scheme in locless_schemes:
safe_url = True
for part in url[2:]:
if ":" in part:
safe_url = False
if self.safe_mode and not safe_url:
return ''
else:
return urlunparse(url)
class ImagePattern(LinkPattern):
""" Return a img element from the given match. """
def handleMatch(self, m):
el = etree.Element("img")
src_parts = m.group(9).split()
if src_parts:
src = src_parts[0]
if src[0] == "<" and src[-1] == ">":
src = src[1:-1]
el.set('src', self.sanitize_url(src))
else:
el.set('src', "")
if len(src_parts) > 1:
el.set('title', dequote(" ".join(src_parts[1:])))
if ENABLE_ATTRIBUTES:
truealt = handleAttributes(m.group(2), el)
else:
truealt = m.group(2)
el.set('alt', truealt)
return el
class ReferencePattern(LinkPattern):
""" Match to a stored reference and return link element. """
def handleMatch(self, m):
if m.group(9):
id = m.group(9).lower()
else:
# if we got something like "[Google][]"
# we'll use "google" as the id
id = m.group(2).lower()
if not self.references.has_key(id): # ignore undefined refs
return None
href, title = self.references[id]
text = m.group(2)
return self.makeTag(href, title, text)
def makeTag(self, href, title, text):
el = etree.Element('a')
el.set('href', self.sanitize_url(href))
if title:
el.set('title', title)
el.text = text
return el
class ImageReferencePattern (ReferencePattern):
""" Match to a stored reference and return img element. """
def makeTag(self, href, title, text):
el = etree.Element("img")
el.set("src", self.sanitize_url(href))
if title:
el.set("title", title)
el.set("alt", text)
return el
class AutolinkPattern (Pattern):
""" Return a link Element given an autolink (``). """
def handleMatch(self, m):
el = etree.Element("a")
el.set('href', m.group(2))
el.text = AtomicString(m.group(2))
return el
class AutomailPattern (Pattern):
"""
Return a mailto link Element given an automail link (``).
"""
def handleMatch(self, m):
el = etree.Element('a')
email = m.group(2)
if email.startswith("mailto:"):
email = email[len("mailto:"):]
def codepoint2name(code):
"""Return entity definition by code, or the code if not defined."""
entity = htmlentitydefs.codepoint2name.get(code)
if entity:
return "%s%s;" % (AMP_SUBSTITUTE, entity)
else:
return "%s#%d;" % (AMP_SUBSTITUTE, code)
letters = [codepoint2name(ord(letter)) for letter in email]
el.text = AtomicString(''.join(letters))
mailto = "mailto:" + email
mailto = "".join([AMP_SUBSTITUTE + '#%d;' %
ord(letter) for letter in mailto])
el.set('href', mailto)
return el
ESCAPE_PATTERN = SimpleTextPattern(ESCAPE_RE)
NOT_STRONG_PATTERN = SimpleTextPattern(NOT_STRONG_RE)
BACKTICK_PATTERN = BacktickPattern(BACKTICK_RE)
STRONG_PATTERN = SimpleTagPattern(STRONG_RE, 'strong')
EMPHASIS_PATTERN = SimpleTagPattern(EMPHASIS_RE, 'em')
EMPHASIS_PATTERN_2 = SimpleTagPattern(EMPHASIS_2_RE, 'em')
STRONG_EM_PATTERN = DoubleTagPattern(STRONG_EM_RE, 'strong,em')
LINE_BREAK_PATTERN = SubstituteTagPattern(LINE_BREAK_RE, 'br')
LINE_BREAK_PATTERN_2 = SubstituteTagPattern(LINE_BREAK_2_RE, 'br')
LINK_PATTERN = LinkPattern(LINK_RE)
IMAGE_LINK_PATTERN = ImagePattern(IMAGE_LINK_RE)
IMAGE_REFERENCE_PATTERN = ImageReferencePattern(IMAGE_REFERENCE_RE)
REFERENCE_PATTERN = ReferencePattern(REFERENCE_RE)
HTML_PATTERN = HtmlPattern(HTML_RE)
ENTITY_PATTERN = HtmlPattern(ENTITY_RE)
AUTOLINK_PATTERN = AutolinkPattern(AUTOLINK_RE)
AUTOMAIL_PATTERN = AutomailPattern(AUTOMAIL_RE)
"""
POST-PROCESSORS
=============================================================================
Markdown also allows post-processors, which are similar to preprocessors in
that they need to implement a "run" method. However, they are run after core
processing.
There are two types of post-processors: Postprocessor and TextPostprocessor
"""
class Postprocessor:
"""
Postprocessors are run before the ElementTree serialization.
Each Postprocessor implements a "run" method that takes a pointer to a
ElementTree, modifies it as necessary and returns a ElementTree
document.
Postprocessors must extend markdown.Postprocessor.
"""
def run(self, root):
"""
Subclasses of Postprocessor should implement a `run` method, which
takes a root Element. Method can return another Element, and global
root Element will be replaced, or just modify current and return None.
"""
pass
class TextPostprocessor:
"""
TextPostprocessors are run after the ElementTree it converted back into text.
Each TextPostprocessor implements a "run" method that takes a pointer to a
text string, modifies it as necessary and returns a text string.
TextPostprocessors must extend markdown.TextPostprocessor.
"""
def run(self, text):
"""
Subclasses of TextPostprocessor should implement a `run` method, which
takes the html document as a single text string and returns a
(possibly modified) string.
"""
pass
class PrettifyPostprocessor(Postprocessor):
"""Add linebreaks to the html document."""
def _prettifyETree(self, elem):
"""Recursively add linebreaks to ElementTree children."""
i = "\n"
if isBlockLevel(elem.tag) and elem.tag not in ['code', 'pre']:
if (not elem.text or not elem.text.strip()) \
and len(elem) and isBlockLevel(elem[0].tag):
elem.text = i
for e in elem:
if isBlockLevel(e.tag):
self._prettifyETree(e)
if not elem.tail or not elem.tail.strip():
elem.tail = i
if not elem.tail or not elem.tail.strip():
elem.tail = i
def run(self, root):
""".Add linebreaks to ElementTree root object."""
self._prettifyETree(root)
# Do
's seperately as they are often in the middle of
# inline content and missed by _prettifyETree.
brs = root.getiterator('br')
for br in brs:
if not br.tail or not br.tail.strip():
br.tail = '\n'
else:
br.tail = '\n%s' % br.tail
PRETTIFYPOSTPROCESSOR = PrettifyPostprocessor()
class RawHtmlTextPostprocessor(TextPostprocessor):
""" Restore raw html to the document. """
def __init__(self):
pass
def run(self, text):
""" Iterate over html stash and restore "safe" html. """
for i in range(self.stash.html_counter):
html, safe = self.stash.rawHtmlBlocks[i]
if self.safeMode and not safe:
if str(self.safeMode).lower() == 'escape':
html = self.escape(html)
elif str(self.safeMode).lower() == 'remove':
html = ''
else:
html = HTML_REMOVED_TEXT
if safe or not self.safeMode:
text = text.replace("%s
" % (HTML_PLACEHOLDER % i),
html + "\n")
text = text.replace(HTML_PLACEHOLDER % i, html)
return text
def escape(self, html):
""" Basic html escaping """
html = html.replace('&', '&')
html = html.replace('<', '<')
html = html.replace('>', '>')
return html.replace('"', '"')
RAWHTMLTEXTPOSTPROCESSOR = RawHtmlTextPostprocessor()
class AndSubstitutePostprocessor(TextPostprocessor):
""" Restore valid entities """
def __init__(self):
pass
def run(self, text):
text = text.replace(AMP_SUBSTITUTE, "&")
return text
AMPSUBSTITUTETEXTPOSTPROCESSOR = AndSubstitutePostprocessor()
"""
MISC AUXILIARY CLASSES
=============================================================================
"""
class AtomicString(unicode):
"""A string which should not be further processed."""
pass
class HtmlStash:
"""
This class is used for stashing HTML objects that we extract
in the beginning and replace with place-holders.
"""
def __init__ (self):
""" Create a HtmlStash. """
self.html_counter = 0 # for counting inline html segments
self.rawHtmlBlocks=[]
def store(self, html, safe=False):
"""
Saves an HTML segment for later reinsertion. Returns a
placeholder string that needs to be inserted into the
document.
Keyword arguments:
* html: an html segment
* safe: label an html segment as safe for safemode
Returns : a placeholder string
"""
self.rawHtmlBlocks.append((html, safe))
placeholder = HTML_PLACEHOLDER % self.html_counter
self.html_counter += 1
return placeholder
def rest(self):
self.html_counter = 0
self.rawHtmlBlocks = []
class InlineStash:
def __init__(self):
""" Create a InlineStash. """
self.prefix = INLINE_PLACEHOLDER_PREFIX
self.suffix = ETX
self._nodes = {}
self.phLength = 4 + len(self.prefix) + len(self.suffix)
self._placeholder_re = re.compile(INLINE_PLACEHOLDER % r'([0-9]{4})')
def _genPlaceholder(self, type):
""" Generate a placeholder """
id = "%04d" % len(self._nodes)
hash = INLINE_PLACEHOLDER % id
return hash, id
def extractId(self, data, index):
"""
Extract id from data string, start from index
Keyword arguments:
* data: string
* index: index, from which we start search
Returns: placeholder id and string index, after
found placeholder
"""
m = self._placeholder_re.search(data, index)
if m:
return m.group(1), m.end()
else:
return None, index + 1
def isin(self, id):
""" Check if node with given id exists in stash """
return self._nodes.has_key(id)
def get(self, id):
""" Return node by id """
return self._nodes.get(id)
def add(self, node, type):
""" Add node to stash """
pholder, id = self._genPlaceholder(type)
self._nodes[id] = node
return pholder
def rest(self):
""" Reset instance """
self._nodes = {}
"""
CORE MARKDOWN
=============================================================================
The core part is still quite messy, despite substantial refactoring. If you
are thinking of extending the syntax, see first if you can do it through
pre-processors, post-processors, inline patterns or a combination of the three.
"""
def _wrapRe(raw_re) : return re.compile("^%s$" % raw_re, re.DOTALL)
CORE_RE = {
'header': _wrapRe(r'(#{1,6})[ \t]*(.*?)[ \t]*(#*)'), # # A title
'reference-def': _wrapRe(r'(\ ?\ ?\ ?)\[([^\]]*)\]:\s*([^ ]*)(.*)'),
# [Google]: http://www.google.com/
'containsline': _wrapRe(r'([-]*)$|^([=]*)'), # -----, =====, etc.
'ol': _wrapRe(r'[ ]{0,3}[\d]*\.\s+(.*)'), # 1. text
'ul': _wrapRe(r'[ ]{0,3}[*+-]\s+(.*)'), # "* text"
'isline1': _wrapRe(r'(\**)'), # ***
'isline2': _wrapRe(r'(\-*)'), # ---
'isline3': _wrapRe(r'(\_*)'), # ___
'tabbed': _wrapRe(r'((\t)|( ))(.*)'), # an indented line
'quoted': _wrapRe(r'[ ]{0,2}> ?(.*)'), # a quoted block ("> ...")
'containsline': re.compile(r'^([-]*)$|^([=]*)$', re.M),
'attr': re.compile("\{@([^\}]*)=([^\}]*)}") # {@id=123}
}
class Markdown:
"""Converts markdown to HTML."""
def __init__(self,
extensions=[],
extension_configs={},
safe_mode = False):
"""
Creates a new Markdown instance.
Keyword arguments:
* extensions: A list of extensions.
If they are of type string, the module mdx_name.py will be loaded.
If they are a subclass of markdown.Extension, they will be used
as-is.
* extension-configs: Configuration setting for extensions.
* safe_mode: Disallow raw html. One of "remove", "replace" or "escape".
"""
self.source = None
self.safeMode = safe_mode
self.registeredExtensions = []
self.docType = ""
self.stripTopLevelTags = True
self.textPreprocessors = [HTML_BLOCK_PREPROCESSOR]
self.preprocessors = [HEADER_PREPROCESSOR,
LINE_PREPROCESSOR,
# A footnote preprocessor will
# get inserted here
REFERENCE_PREPROCESSOR]
self.postprocessors = [PRETTIFYPOSTPROCESSOR,
# a footnote postprocessor will get
# inserted later
]
self.textPostprocessors = [# a footnote postprocessor will get
# inserted here
RAWHTMLTEXTPOSTPROCESSOR,
AMPSUBSTITUTETEXTPOSTPROCESSOR]
self.prePatterns = []
self.inlinePatterns = [
BACKTICK_PATTERN,
ESCAPE_PATTERN,
REFERENCE_PATTERN,
LINK_PATTERN,
IMAGE_LINK_PATTERN,
IMAGE_REFERENCE_PATTERN,
AUTOLINK_PATTERN,
AUTOMAIL_PATTERN,
LINE_BREAK_PATTERN_2,
LINE_BREAK_PATTERN,
HTML_PATTERN,
ENTITY_PATTERN,
NOT_STRONG_PATTERN,
STRONG_EM_PATTERN,
STRONG_PATTERN,
EMPHASIS_PATTERN,
EMPHASIS_PATTERN_2
# The order of the handlers matters!!!
]
self.inlineStash = InlineStash()
self.references = {}
self.htmlStash = HtmlStash()
self.registerExtensions(extensions = extensions,
configs = extension_configs)
self.reset()
def registerExtensions(self, extensions, configs):
"""
Register extensions with this instance of Markdown.
Keyword aurguments:
* extensions: A list of extensions, which can either
be strings or objects. See the docstring on Markdown.
* configs: A dictionary mapping module names to config options.
"""
for ext in extensions:
if isinstance(ext, basestring):
ext = load_extension(ext, configs.get(ext, []))
elif hasattr(ext, 'extendMarkdown'):
# Looks like an Extension.
# Nothing to do here.
pass
else:
message(ERROR, "Incorrect type! Extension '%s' is "
"neither a string or an Extension." %(repr(ext)))
continue
ext.extendMarkdown(self, globals())
def registerExtension(self, extension):
""" This gets called by the extension """
self.registeredExtensions.append(extension)
def reset(self):
"""
Resets all state variables so that we can start with a new text.
"""
self.inlineStash.rest()
self.htmlStash.rest()
self.references.clear()
HTML_BLOCK_PREPROCESSOR.stash = self.htmlStash
LINE_PREPROCESSOR.stash = self.htmlStash
REFERENCE_PREPROCESSOR.references = self.references
HTML_PATTERN.stash = self.htmlStash
ENTITY_PATTERN.stash = self.htmlStash
REFERENCE_PATTERN.references = self.references
IMAGE_REFERENCE_PATTERN.references = self.references
RAWHTMLTEXTPOSTPROCESSOR.stash = self.htmlStash
RAWHTMLTEXTPOSTPROCESSOR.safeMode = self.safeMode
for extension in self.registeredExtensions:
extension.reset()
for pattern in self.inlinePatterns:
pattern.safe_mode = self.safeMode
def _transform(self):
"""Transform the Markdown text into a XHTML body document.
Returns: ElementTree object
"""
# Setup the document
self.root = etree.Element("div")
# Split into lines and run the preprocessors that will work with
# self.lines
self.lines = self.source.split("\n")
# Run the pre-processors on the lines
for prep in self.preprocessors :
self.lines = prep.run(self.lines)
# Create a ElementTree from the lines
buffer = []
for line in self.lines:
if line.startswith("#"):
self._processSection(self.root, buffer)
buffer = [line]
else:
buffer.append(line)
self._processSection(self.root, buffer)
return etree.ElementTree(self.root)
def _processSection(self, parent_elem, lines,
inList=0, looseList=0):
"""
Process a section of a source document, looking for high
level structural elements like lists, block quotes, code
segments, html blocks, etc. Some those then get stripped
of their high level markup (e.g. get unindented) and the
lower-level markup is processed recursively.
Keyword arguments:
* parent_elem: A ElementTree element to which the content will be added.
* lines: a list of lines
* inList: a level
Returns: None
"""
# Loop through lines until none left.
while lines:
# Skipping empty line
if not lines[0]:
lines = lines[1:]
continue
# Check if this section starts with a list, a blockquote or
# a code block
processFn = { 'ul': self._processUList,
'ol': self._processOList,
'quoted': self._processQuote,
'tabbed': self._processCodeBlock}
for regexp in ['ul', 'ol', 'quoted', 'tabbed']:
m = CORE_RE[regexp].match(lines[0])
if m:
processFn[regexp](parent_elem, lines, inList)
return
# We are NOT looking at one of the high-level structures like
# lists or blockquotes. So, it's just a regular paragraph
# (though perhaps nested inside a list or something else). If
# we are NOT inside a list, we just need to look for a blank
# line to find the end of the block. If we ARE inside a
# list, however, we need to consider that a sublist does not
# need to be separated by a blank line. Rather, the following
# markup is legal:
#
# * The top level list item
#
# Another paragraph of the list. This is where we are now.
# * Underneath we might have a sublist.
#
if inList:
start, lines = self._linesUntil(lines, (lambda line:
CORE_RE['ul'].match(line)
or CORE_RE['ol'].match(line)
or not line.strip()))
self._processSection(parent_elem, start,
inList - 1, looseList = looseList)
inList = inList-1
else: # Ok, so it's just a simple block
paragraph, lines = self._linesUntil(lines, lambda line:
not line.strip() or line[0] == '>')
if len(paragraph) and paragraph[0].startswith('#'):
self._processHeader(parent_elem, paragraph)
elif len(paragraph) and \
CORE_RE["isline3"].match(paragraph[0]):
self._processHR(parent_elem)
lines = paragraph[1:] + lines
elif paragraph:
self._processParagraph(parent_elem, paragraph,
inList, looseList)
if lines and not lines[0].strip():
lines = lines[1:] # skip the first (blank) line
def _processHR(self, parentElem):
hr = etree.SubElement(parentElem, "hr")
def _processHeader(self, parentElem, paragraph):
m = CORE_RE['header'].match(paragraph[0])
if m:
level = len(m.group(1))
h = etree.SubElement(parentElem, "h%d" % level)
h.text = m.group(2).strip()
else:
message(CRITICAL, "We've got a problem header!")
def _processParagraph(self, parentElem, paragraph, inList, looseList):
if ( parentElem.tag == 'li'
and not (looseList or parentElem.getchildren())):
# If this is the first paragraph inside "li", don't
# put around it - append the paragraph bits directly
# onto parentElem
el = parentElem
else:
# Otherwise make a "p" element
el = etree.SubElement(parentElem, "p")
dump = []
# Searching for hr or header
for line in paragraph:
# it's hr
if CORE_RE["isline3"].match(line):
el.text = "\n".join(dump)
self._processHR(el)
dump = []
# it's header
elif line.startswith("#"):
el.text = "\n".join(dump)
self._processHeader(parentElem, [line])
dump = []
else:
dump.append(line)
if dump:
text = "\n".join(dump)
el.text = text
def _processUList(self, parentElem, lines, inList):
self._processList(parentElem, lines, inList,
listexpr='ul', tag = 'ul')
def _processOList(self, parentElem, lines, inList):
self._processList(parentElem, lines, inList,
listexpr='ol', tag = 'ol')
def _processList(self, parentElem, lines, inList, listexpr, tag):
"""
Given a list of document lines starting with a list item,
finds the end of the list, breaks it up, and recursively
processes each list item and the remainder of the text file.
Keyword arguments:
* parentElem: A ElementTree element to which the content will be added
* lines: a list of lines
* inList: a level
Returns: None
"""
ul = etree.SubElement(parentElem, tag) # ul might actually be '
'
looseList = 0
# Make a list of list items
items = []
item = -1
i = 0 # a counter to keep track of where we are
for line in lines:
loose = 0
if not line.strip():
# If we see a blank line, this _might_ be the end of the list
i += 1
loose = 1
# Find the next non-blank line
for j in range(i, len(lines)):
if lines[j].strip():
next = lines[j]
break
else:
# There is no more text => end of the list
break
# Check if the next non-blank line is still a part of the list
if ( CORE_RE[listexpr].match(next) or
CORE_RE['tabbed'].match(next) ):
# get rid of any white space in the line
items[item].append(line.strip())
looseList = loose or looseList
continue
else:
break # found end of the list
# Now we need to detect list items (at the current level)
# while also detabing child elements if necessary
for expr in ['ul', 'ol', 'tabbed']:
m = CORE_RE[expr].match(line)
if m:
if expr in ['ul', 'ol']: # We are looking at a new item
#if m.group(1) :
# Removed the check to allow for a blank line
# at the beginning of the list item
items.append([m.group(1)])
item += 1
elif expr == 'tabbed': # This line needs to be detabbed
items[item].append(m.group(4)) #after the 'tab'
i += 1
break
else:
items[item].append(line) # Just regular continuation
i += 1 # added on 2006.02.25
else:
i += 1
# Add the ElementTree elements
for item in items:
li = etree.SubElement(ul, "li")
self._processSection(li, item, inList + 1, looseList = looseList)
# Process the remaining part of the section
self._processSection(parentElem, lines[i:], inList)
def _linesUntil(self, lines, condition):
"""
A utility function to break a list of lines upon the
first line that satisfied a condition. The condition
argument should be a predicate function.
"""
i = -1
for line in lines:
i += 1
if condition(line):
break
else:
i += 1
return lines[:i], lines[i:]
def _processQuote(self, parentElem, lines, inList):
"""
Given a list of document lines starting with a quote finds
the end of the quote, unindents it and recursively
processes the body of the quote and the remainder of the
text file.
Keyword arguments:
* parentElem: ElementTree element to which the content will be added
* lines: a list of lines
* inList: a level
Returns: None
"""
dequoted = []
i = 0
blank_line = False # allow one blank line between paragraphs
for line in lines:
m = CORE_RE['quoted'].match(line)
if m:
dequoted.append(m.group(1))
i += 1
blank_line = False
elif not blank_line and line.strip() != '':
dequoted.append(line)
i += 1
elif not blank_line and line.strip() == '':
dequoted.append(line)
i += 1
blank_line = True
else:
break
blockquote = etree.SubElement(parentElem, "blockquote")
self._processSection(blockquote, dequoted, inList)
self._processSection(parentElem, lines[i:], inList)
def _processCodeBlock(self, parentElem, lines, inList):
"""
Given a list of document lines starting with a code block
finds the end of the block, puts it into the ElementTree verbatim
wrapped in ("") and recursively processes the
the remainder of the text file.
Keyword arguments:
* parentElem: ElementTree element to which the content will be added
* lines: a list of lines
* inList: a level
Returns: None
"""
detabbed, theRest = self.detectTabbed(lines)
pre = etree.SubElement(parentElem, "pre")
code = etree.SubElement(pre, "code")
text = "\n".join(detabbed).rstrip()+"\n"
code.text = AtomicString(text)
self._processSection(parentElem, theRest, inList)
def detectTabbed(self, lines):
""" Find indented text and remove indent before further proccesing.
Keyword arguments:
* lines: an array of strings
* fn: a function that returns a substring of a string
if the string matches the necessary criteria
Returns: a list of post processes items and the unused
remainder of the original list
"""
items = []
item = -1
i = 0 # to keep track of where we are
def detab(line):
match = CORE_RE['tabbed'].match(line)
if match:
return match.group(4)
for line in lines:
if line.strip(): # Non-blank line
line = detab(line)
if line:
items.append(line)
i += 1
continue
else:
return items, lines[i:]
else: # Blank line: _maybe_ we are done.
i += 1 # advance
# Find the next non-blank line
for j in range(i, len(lines)):
if lines[j].strip():
next_line = lines[j]; break
else:
break # There is no more text; we are done.
# Check if the next non-blank line is tabbed
if detab(next_line): # Yes, more work to do.
items.append("")
continue
else:
break # No, we are done.
else:
i += 1
return items, lines[i:]
def _handleInline(self, data, patternIndex=0):
"""
Process string with inline patterns and replace it
with placeholders
Keyword arguments:
* data: A line of Markdown text
* patternIndex: The index of the inlinePattern to start with
Returns: String with placeholders.
"""
if isinstance(data, AtomicString):
return data
startIndex = 0
while patternIndex < len(self.inlinePatterns):
data, matched, startIndex = self._applyInline(
self.inlinePatterns[patternIndex],
data, patternIndex, startIndex)
if not matched:
patternIndex += 1
return data
def _applyInline(self, pattern, data, patternIndex, startIndex=0):
"""
Check if the line fits the pattern, create the necessary
elements, add it to InlineStash
Keyword arguments:
* data: the text to be processed
* pattern: the pattern to be checked
* patternIndex: index of current pattern
* startIndex: string index, from which we starting search
Returns: String with placeholders instead of ElementTree elements.
"""
match = pattern.getCompiledRegExp().match(data[startIndex:])
leftData = data[:startIndex]
if not match:
return data, False, 0
node = pattern.handleMatch(match)
if node is None:
return data, True, len(leftData) + match.span(len(match.groups()))[0]
if not isString(node):
if not isinstance(node.text, AtomicString):
# We need to process current node too
for child in [node] + node.getchildren():
if not isString(node):
if child.text:
child.text = self._handleInline(child.text,
patternIndex + 1)
if child.tail:
child.tail = self._handleInline(child.tail,
patternIndex)
pholder = self.inlineStash.add(node, pattern.type())
return "%s%s%s%s" % (leftData,
match.group(1),
pholder, match.groups()[-1]), True, 0
def _processElementText(self, node, subnode, isText=True):
"""
Process placeholders in Element.text or Element.tail
of Elements popped from InlineStash
Keywords arguments:
* node: parent node
* subnode: processing node
* isText: bool variable, True - it's text, False - it's tail
Returns: None
"""
if isText:
text = subnode.text
subnode.text = None
else:
text = subnode.tail
subnode.tail = None
childResult = self._processPlaceholders(text, subnode)
if not isText and node is not subnode:
pos = node.getchildren().index(subnode)
node.remove(subnode)
else:
pos = 0
childResult.reverse()
for newChild in childResult:
node.insert(pos, newChild)
def _processPlaceholders(self, data, parent):
"""
Process string with placeholders and generate ElementTree tree.
Keyword arguments:
* data: string with placeholders instead of ElementTree elements.
* parent: Element, which contains processing inline data
Returns: list with ElementTree elements with applied inline patterns.
"""
def linkText(text):
if text:
if result:
if result[-1].tail:
result[-1].tail += text
else:
result[-1].tail = text
else:
if parent.text:
parent.text += text
else:
parent.text = text
result = []
prefix = self.inlineStash.prefix
strartIndex = 0
while data:
index = data.find(prefix, strartIndex)
if index != -1:
id, phEndIndex = self.inlineStash.extractId(data, index)
if self.inlineStash.isin(id):
node = self.inlineStash.get(id)
if index > 0:
text = data[strartIndex:index]
linkText(text)
if not isString(node): # it's Element
for child in [node] + node.getchildren():
if child.tail:
if child.tail.strip():
self._processElementText(node, child, False)
if child.text:
if child.text.strip():
self._processElementText(child, child)
else: # it's just a string
linkText(node)
strartIndex = phEndIndex
continue
strartIndex = phEndIndex
result.append(node)
else: # wrong placeholder
end = index + len(prefix)
linkText(data[strartIndex:end])
strartIndex = end
else:
text = data[strartIndex:]
linkText(text)
data = ""
return result
def applyInlinePatterns(self, markdownTree):
"""
Iterate over ElementTree, find elements with inline tag,
apply inline patterns and append newly created Elements to tree.
If you don't whant process your data with inline paterns,
instead of normal string, use subclass AtomicString:
`node.text = AtomicString("data won't be processed with inline patterns")`
Keyword arguments:
* markdownTree: ElementTree object, representing Markdown tree.
Returns: ElementTree object with applied inline patterns.
"""
stack = [markdownTree.getroot()]
while stack:
currElement = stack.pop()
insertQueue = []
for child in currElement.getchildren():
if child.text and not isinstance(child.text, AtomicString):
text = child.text
child.text = None
lst = self._processPlaceholders(self._handleInline(
text), child)
stack += lst
insertQueue.append((child, lst))
if child.getchildren():
stack.append(child)
for element, lst in insertQueue:
if element.text:
element.text = handleAttributes(element.text, element)
i = 0
for newChild in lst:
# Processing attributes
if newChild.tail:
newChild.tail = handleAttributes(newChild.tail,
element)
if newChild.text:
newChild.text = handleAttributes(newChild.text,
newChild)
element.insert(i, newChild)
i += 1
return markdownTree
def markdownToTree(self, source=None):
"""Create ElementTree, without applying inline paterns.
Keyword arguments:
* source: An ascii or unicode string of Markdown formated text.
Returns: ElementTree object.
"""
try:
self.source = unicode(self.source)
except UnicodeDecodeError:
message(CRITICAL, 'UnicodeDecodeError: Markdown only accepts unicode or ascii input.')
return u""
# Fixup the source text
self.source = self.source.replace(STX, "")
self.source = self.source.replace(ETX, "")
self.source = self.source.replace("\r\n", "\n").replace("\r", "\n")
self.source += "\n\n"
self.source = self.source.expandtabs(TAB_LENGTH)
for pp in self.textPreprocessors:
self.source = pp.run(self.source)
markdownTree = self._transform()
return markdownTree
def convert (self, source):
"""Create the document in XHTML format.
Keyword arguments:
* source: An ascii or unicode string of Markdown formated text.
Returns: A serialized XHTML body.
"""
self.source = source
if not self.source:
return u""
tree = self.markdownToTree(source)
root = self.applyInlinePatterns(tree).getroot()
# Run the post-processors
for postprocessor in self.postprocessors:
postprocessor.stash = self.htmlStash
newRoot = postprocessor.run(root)
if newRoot:
root = newRoot
xml, length = codecs.utf_8_decode(etree.tostring(root, encoding="utf8"))
if self.stripTopLevelTags:
xml = xml.strip()[44:-7] + "\n"
# Run the text post-processors
for pp in self.textPostprocessors:
xml = pp.run(xml)
return xml.strip()
def __str__(self):
""" Report info about instance. Markdown always returns unicode."""
if self.source is None:
status = 'in which no source text has been assinged.'
else:
status = 'which contains %d chars and %d line(s) of source.'%\
(len(self.source), self.source.count('\n')+1)
return 'An instance of "%s" %s'% (self.__class__, status)
__unicode__ = convert # markdown should always return a unicode string
"""
EXPORTED FUNCTIONS
=============================================================================
Those are the two functions we really mean to export: markdown() and
markdownFromFile().
"""
def markdownFromFile(input = None,
output = None,
extensions = [],
encoding = None,
safe = False):
"""Converts a markdown file and returns the HTML as a unicode string.
Used from the command-line, although may be useful in other situations.
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
filename or stdout in the same encoding as the source file.
**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: Name of source text file.
* output: Name of output file. Writes to stdout if `None`.
* extensions: A list of extension names (may contain config args).
* encoding: Encoding of input and output files. Defaults to utf-8.
* safe_mode: Disallow raw html. One of "remove", "replace" or "escape".
"""
encoding = encoding or "utf-8"
# Read the source
input_file = codecs.open(input, mode="r", encoding=encoding)
text = input_file.read()
input_file.close()
text = text.lstrip(u'\ufeff') # remove the byte-order mark
# Convert
html = markdown(text, extensions, safe_mode = safe)
# Write to file or stdout
if output:
output_file = codecs.open(output, "w", encoding=encoding)
output_file.write(html)
output_file.close()
else:
sys.stdout.write(html.encode(encoding))
def markdown(text,
extensions = [],
safe_mode = False):
"""
Convenience wrapper function for `Markdown` class.
Useful in a typical use case. Initializes an instance of the `Markdown`
class, loads any extensions and runs the parser on the given text.
Keyword arguments:
* text: An ascii or Unicode string of Markdown formatted text.
* extensions: A list of extension names (may contain config args).
* safe_mode: Disallow raw html. One of "remove", "replace" or "escape".
Returns: An HTML document as a string.
"""
message(DEBUG, "in markdown.markdown(), received text:\n%s" % text)
extensions = [load_extension(e) for e in extensions]
md = Markdown(extensions=extensions,
safe_mode = safe_mode)
return md.convert(text)
"""
Extensions
-----------------------------------------------------------------------------
"""
class Extension:
""" Base class for extensions to subclass. """
def __init__(self, configs = {}):
"""Create an instance of an Extention.
Keyword arguments:
* configs: A dict of configuration setting used by an Extension.
"""
self.config = configs
def getConfig(self, key):
""" Return a setting for the given key or an empty string. """
if self.config.has_key(key):
return self.config[key][0]
else:
return ""
def getConfigInfo(self):
""" Return all config settings as a list of tuples. """
return [(key, self.config[key][1]) for key in self.config.keys()]
def setConfig(self, key, value):
""" Set a config setting for `key` with the given `value`. """
self.config[key][0] = value
def extendMarkdown(self, md, md_globals):
"""
Add the various proccesors and patterns to the Markdown Instance.
This method must be overriden by every extension.
Ketword arguments:
* md: The Markdown instance.
* md_globals: All global variables availabel in the markdown module
namespace.
"""
pass
def load_extension(ext_name, configs = []):
"""
Load extension by name, then return the module.
The extension name may contain arguments as part of the string in the
following format:
"extname(key1=value1,key2=value2)"
Print an error message and exit on failure.
"""
# I am making the assumption that the order of config options
# does not matter.
configs = dict(configs)
pos = ext_name.find("(")
if pos > 0:
ext_args = ext_name[pos+1:-1]
ext_name = ext_name[:pos]
pairs = [x.split("=") for x in ext_args.split(",")]
configs.update([(x.strip(), y.strip()) for (x, y) in pairs])
ext_module = 'markdown_extensions'
module_name = '.'.join([ext_module, ext_name])
extension_module_name = '_'.join(['mdx', ext_name])
try:
module = __import__(module_name, {}, {}, [ext_module])
except ImportError:
try:
module = __import__(extension_module_name)
except:
message(WARN,
"Failed loading extension '%s' from '%s' or '%s' "
"- continuing without."
% (ext_name, module_name, extension_module_name) )
# Return a dummy (do nothing) Extension as silent failure
return Extension(configs={})
return module.makeExtension(configs.items())
# Extensions should use "markdown.etree" instead of "etree" (or do `from
# markdown import etree`). Do not import it by yourself.
etree = importETree()
"""
COMMAND-LINE SPECIFIC STUFF
=============================================================================
The rest of the code is specifically for handling the case where Python
Markdown is called from the command line.
"""
OPTPARSE_WARNING = """
Python 2.3 or higher required for advanced command line options.
For lower versions of Python use:
%s INPUT_FILE > OUTPUT_FILE
""" % EXECUTABLE_NAME_FOR_USAGE
def parse_options():
"""
Define and parse `optparse` options for command-line usage.
"""
try:
optparse = __import__("optparse")
except:
if len(sys.argv) == 2:
return {'input': sys.argv[1],
'output': None,
'safe': False,
'extensions': [],
'encoding': None }, CRITICAL
else:
print OPTPARSE_WARNING
return None, None
parser = optparse.OptionParser(usage="%prog INPUTFILE [options]")
parser.add_option("-f", "--file", dest="filename",
help="write output to OUTPUT_FILE",
metavar="OUTPUT_FILE")
parser.add_option("-e", "--encoding", dest="encoding",
help="encoding for input and output files",)
parser.add_option("-q", "--quiet", default = CRITICAL,
action="store_const", const=CRITICAL+10, dest="verbose",
help="suppress all messages")
parser.add_option("-v", "--verbose",
action="store_const", const=INFO, dest="verbose",
help="print info messages")
parser.add_option("-s", "--safe", dest="safe", default=False,
metavar="SAFE_MODE",
help="safe mode ('replace', 'remove' or 'escape' user's HTML tag)")
parser.add_option("--noisy",
action="store_const", const=DEBUG, dest="verbose",
help="print debug messages")
parser.add_option("-x", "--extension", action="append", dest="extensions",
help = "load extension EXTENSION", metavar="EXTENSION")
(options, args) = parser.parse_args()
if not len(args) == 1:
parser.print_help()
return None, None
else:
input_file = args[0]
if not options.extensions:
options.extensions = []
return {'input': input_file,
'output': options.filename,
'safe': options.safe,
'extensions': options.extensions,
'encoding': options.encoding }, options.verbose
def command_line_run():
"""Run Markdown from the command line."""
# Setup a logger manually for compatibility with Python 2.3
logger = logging.getLogger('MARKDOWN')
logger.setLevel(COMMAND_LINE_LOGGING_LEVEL)
logger.addHandler(logging.StreamHandler())
# Parse options and adjust logging level if necessary
options, logging_level = parse_options()
if not options: sys.exit(0)
if logging_level: logging.getLogger('MARKDOWN').setLevel(logging_level)
# Run
markdownFromFile(**options)
if __name__ == '__main__':
command_line_run()