lib/django-1.4/django/utils/html.py - external/googleappengine/python - Git at Google

 """HTML utilities suitable for global use."""

 import re
 import string
 import urllib
 import urlparse

 from django.utils.safestring import SafeData, mark_safe
 from django.utils.encoding import smart_str, force_unicode
 from django.utils.functional import allow_lazy
 from django.utils.text import normalize_newlines

 # Configuration for urlize() function.
 TRAILING_PUNCTUATION = ['.', ',', ':', ';']
 WRAPPING_PUNCTUATION = [('(', ')'), ('<', '>'), ('&lt;', '&gt;')]

 # List of possible strings used for bullets in bulleted lists.
 DOTS = [u'&middot;', u'*', u'\u2022', u'&#149;', u'&bull;', u'&#8226;']

 unencoded_ampersands_re = re.compile(r'&(?!(\w+|#\d+);)')
 unquoted_percents_re = re.compile(r'%(?![0-9A-Fa-f]{2})')
 word_split_re = re.compile(r'(\s+)')
 simple_url_re = re.compile(r'^https?://\w')
 simple_url_2_re = re.compile(r'^www\.|^(?!http)\w[^@]+\.(com|edu|gov|int|mil|net|org)$')
 simple_email_re = re.compile(r'^\S+@\S+\.\S+$')
 link_target_attribute_re = re.compile(r'(<a [^>]*?)target=[^\s>]+')
 html_gunk_re = re.compile(r'(?:<br clear="all">|<i><\/i>|<b><\/b>|<em><\/em>|<strong><\/strong>|<\/?smallcaps>|<\/?uppercase>)', re.IGNORECASE)
 hard_coded_bullets_re = re.compile(r'((?:<p>(?:%s).*?[a-zA-Z].*?</p>\s*)+)' % '|'.join([re.escape(x) for x in DOTS]), re.DOTALL)
 trailing_empty_content_re = re.compile(r'(?:<p>(?:&nbsp;|\s|<br \/>)*?</p>\s*)+\Z')
 del x # Temporary variable

 def escape(html):
     """
     Returns the given HTML with ampersands, quotes and angle brackets encoded.
     """
     return mark_safe(force_unicode(html).replace('&', '&amp;').replace('<', '&lt;').replace('>', '&gt;').replace('"', '&quot;').replace("'", '&#39;'))
 escape = allow_lazy(escape, unicode)

 _base_js_escapes = (
     ('\\', r'\u005C'),
     ('\'', r'\u0027'),
     ('"', r'\u0022'),
     ('>', r'\u003E'),
     ('<', r'\u003C'),
     ('&', r'\u0026'),
     ('=', r'\u003D'),
     ('-', r'\u002D'),
     (';', r'\u003B'),
     (u'\u2028', r'\u2028'),
     (u'\u2029', r'\u2029')
 )

 # Escape every ASCII character with a value less than 32.
 _js_escapes = (_base_js_escapes +
                tuple([('%c' % z, '\\u%04X' % z) for z in range(32)]))

 def escapejs(value):
     """Hex encodes characters for use in JavaScript strings."""
     for bad, good in _js_escapes:
         value = mark_safe(force_unicode(value).replace(bad, good))
     return value
 escapejs = allow_lazy(escapejs, unicode)

 def conditional_escape(html):
     """
     Similar to escape(), except that it doesn't operate on pre-escaped strings.
     """
     if isinstance(html, SafeData):
         return html
     else:
         return escape(html)

 def linebreaks(value, autoescape=False):
     """Converts newlines into <p> and <br />s."""
     value = normalize_newlines(value)
     paras = re.split('\n{2,}', value)
     if autoescape:
         paras = [u'<p>%s</p>' % escape(p).replace('\n', '<br />') for p in paras]
     else:
         paras = [u'<p>%s</p>' % p.replace('\n', '<br />') for p in paras]
     return u'\n\n'.join(paras)
 linebreaks = allow_lazy(linebreaks, unicode)

 def strip_tags(value):
     """Returns the given HTML with all tags stripped."""
     return re.sub(r'<[^>]*?>', '', force_unicode(value))
 strip_tags = allow_lazy(strip_tags)

 def strip_spaces_between_tags(value):
     """Returns the given HTML with spaces between tags removed."""
     return re.sub(r'>\s+<', '><', force_unicode(value))
 strip_spaces_between_tags = allow_lazy(strip_spaces_between_tags, unicode)

 def strip_entities(value):
     """Returns the given HTML with all entities (&something;) stripped."""
     return re.sub(r'&(?:\w+|#\d+);', '', force_unicode(value))
 strip_entities = allow_lazy(strip_entities, unicode)

 def fix_ampersands(value):
     """Returns the given HTML with all unencoded ampersands encoded correctly."""
     return unencoded_ampersands_re.sub('&amp;', force_unicode(value))
 fix_ampersands = allow_lazy(fix_ampersands, unicode)

 def smart_urlquote(url):
     "Quotes a URL if it isn't already quoted."
     # Handle IDN before quoting.
     scheme, netloc, path, query, fragment = urlparse.urlsplit(url)
     try:
         netloc = netloc.encode('idna') # IDN -> ACE
     except UnicodeError: # invalid domain part
         pass
     else:
         url = urlparse.urlunsplit((scheme, netloc, path, query, fragment))

     # An URL is considered unquoted if it contains no % characters or
     # contains a % not followed by two hexadecimal digits. See #9655.
     if '%' not in url or unquoted_percents_re.search(url):
         # See http://bugs.python.org/issue2637
         url = urllib.quote(smart_str(url), safe='!*\'();:@&=+$,/?#[]~')

     return force_unicode(url)

 def urlize(text, trim_url_limit=None, nofollow=False, autoescape=False):
     """
     Converts any URLs in text into clickable links.

     Works on http://, https://, www. links, and also on links ending in one of
     the original seven gTLDs (.com, .edu, .gov, .int, .mil, .net, and .org).
     Links can have trailing punctuation (periods, commas, close-parens) and
     leading punctuation (opening parens) and it'll still do the right thing.

     If trim_url_limit is not None, the URLs in link text longer than this limit
     will truncated to trim_url_limit-3 characters and appended with an elipsis.

     If nofollow is True, the URLs in link text will get a rel="nofollow"
     attribute.

     If autoescape is True, the link text and URLs will get autoescaped.
     """
     trim_url = lambda x, limit=trim_url_limit: limit is not None and (len(x) > limit and ('%s...' % x[:max(0, limit - 3)])) or x
     safe_input = isinstance(text, SafeData)
     words = word_split_re.split(force_unicode(text))
     for i, word in enumerate(words):
         match = None
         if '.' in word or '@' in word or ':' in word:
             # Deal with punctuation.
             lead, middle, trail = '', word, ''
             for punctuation in TRAILING_PUNCTUATION:
                 if middle.endswith(punctuation):
                     middle = middle[:-len(punctuation)]
                     trail = punctuation + trail
             for opening, closing in WRAPPING_PUNCTUATION:
                 if middle.startswith(opening):
                     middle = middle[len(opening):]
                     lead = lead + opening
                 # Keep parentheses at the end only if they're balanced.
                 if (middle.endswith(closing)
                     and middle.count(closing) == middle.count(opening) + 1):
                     middle = middle[:-len(closing)]
                     trail = closing + trail

             # Make URL we want to point to.
             url = None
             nofollow_attr = ' rel="nofollow"' if nofollow else ''
             if simple_url_re.match(middle):
                 url = smart_urlquote(middle)
             elif simple_url_2_re.match(middle):
                 url = smart_urlquote('http://%s' % middle)
             elif not ':' in middle and simple_email_re.match(middle):
                 local, domain = middle.rsplit('@', 1)
                 try:
                     domain = domain.encode('idna')
                 except UnicodeError:
                     continue
                 url = 'mailto:%s@%s' % (local, domain)
                 nofollow_attr = ''

             # Make link.
             if url:
                 trimmed = trim_url(middle)
                 if autoescape and not safe_input:
                     lead, trail = escape(lead), escape(trail)
                     url, trimmed = escape(url), escape(trimmed)
                 middle = '<a href="%s"%s>%s</a>' % (url, nofollow_attr, trimmed)
                 words[i] = mark_safe('%s%s%s' % (lead, middle, trail))
             else:
                 if safe_input:
                     words[i] = mark_safe(word)
                 elif autoescape:
                     words[i] = escape(word)
         elif safe_input:
             words[i] = mark_safe(word)
         elif autoescape:
             words[i] = escape(word)
     return u''.join(words)
 urlize = allow_lazy(urlize, unicode)

 def clean_html(text):
     """
     Clean the given HTML.  Specifically, do the following:
         * Convert <b> and <i> to <strong> and <em>.
         * Encode all ampersands correctly.
         * Remove all "target" attributes from <a> tags.
         * Remove extraneous HTML, such as presentational tags that open and
           immediately close and <br clear="all">.
         * Convert hard-coded bullets into HTML unordered lists.
         * Remove stuff like "<p>&nbsp;&nbsp;</p>", but only if it's at the
           bottom of the text.
     """
     from django.utils.text import normalize_newlines
     text = normalize_newlines(force_unicode(text))
     text = re.sub(r'<(/?)\s*b\s*>', '<\\1strong>', text)
     text = re.sub(r'<(/?)\s*i\s*>', '<\\1em>', text)
     text = fix_ampersands(text)
     # Remove all target="" attributes from <a> tags.
     text = link_target_attribute_re.sub('\\1', text)
     # Trim stupid HTML such as <br clear="all">.
     text = html_gunk_re.sub('', text)
     # Convert hard-coded bullets into HTML unordered lists.
     def replace_p_tags(match):
         s = match.group().replace(u'</p>', u'</li>')
         for d in DOTS:
             s = s.replace(u'<p>%s' % d, u'<li>')
         return u'<ul>\n%s\n</ul>' % s
     text = hard_coded_bullets_re.sub(replace_p_tags, text)
     # Remove stuff like "<p>&nbsp;&nbsp;</p>", but only if it's at the bottom
     # of the text.
     text = trailing_empty_content_re.sub(u'', text)
     return text
 clean_html = allow_lazy(clean_html, unicode)
	"""HTML utilities suitable for global use."""

	import re
	import string
	import urllib
	import urlparse

	from django.utils.safestring import SafeData, mark_safe
	from django.utils.encoding import smart_str, force_unicode
	from django.utils.functional import allow_lazy
	from django.utils.text import normalize_newlines

	# Configuration for urlize() function.
	TRAILING_PUNCTUATION = ['.', ',', ':', ';']
	WRAPPING_PUNCTUATION = [('(', ')'), ('<', '>'), ('<', '>')]

	# List of possible strings used for bullets in bulleted lists.
	DOTS = [u'·', u'*', u'\u2022', u'', u'•', u'•']

	unencoded_ampersands_re = re.compile(r'&(?!(\w+\|#\d+);)')
	unquoted_percents_re = re.compile(r'%(?![0-9A-Fa-f]{2})')
	word_split_re = re.compile(r'(\s+)')
	simple_url_re = re.compile(r'^https?://\w')
	simple_url_2_re = re.compile(r'^www\.\|^(?!http)\w[^@]+\.(com\|edu\|gov\|int\|mil\|net\|org)$')
	simple_email_re = re.compile(r'^\S+@\S+\.\S+$')
	link_target_attribute_re = re.compile(r'(<a [^>]*?)target=[^\s>]+')
	html_gunk_re = re.compile(r'(?:<br clear="all">\|<i><\/i>\|<b><\/b>\|<em><\/em>\|<strong><\/strong>\|<\/?smallcaps>\|<\/?uppercase>)', re.IGNORECASE)
	hard_coded_bullets_re = re.compile(r'((?:<p>(?:%s).?[a-zA-Z].?</p>\s*)+)' % '\|'.join([re.escape(x) for x in DOTS]), re.DOTALL)
	trailing_empty_content_re = re.compile(r'(?:<p>(?: \|\s\|<br \/>)?</p>\s)+\Z')
	del x # Temporary variable

	def escape(html):
	"""
	Returns the given HTML with ampersands, quotes and angle brackets encoded.
	"""
	return mark_safe(force_unicode(html).replace('&', '&').replace('<', '<').replace('>', '>').replace('"', '"').replace("'", '''))
	escape = allow_lazy(escape, unicode)

	_base_js_escapes = (
	('\\', r'\u005C'),
	('\'', r'\u0027'),
	('"', r'\u0022'),
	('>', r'\u003E'),
	('<', r'\u003C'),
	('&', r'\u0026'),
	('=', r'\u003D'),
	('-', r'\u002D'),
	(';', r'\u003B'),
	(u'\u2028', r'\u2028'),
	(u'\u2029', r'\u2029')
	)

	# Escape every ASCII character with a value less than 32.
	_js_escapes = (_base_js_escapes +
	tuple([('%c' % z, '\\u%04X' % z) for z in range(32)]))

	def escapejs(value):
	"""Hex encodes characters for use in JavaScript strings."""
	for bad, good in _js_escapes:
	value = mark_safe(force_unicode(value).replace(bad, good))
	return value
	escapejs = allow_lazy(escapejs, unicode)

	def conditional_escape(html):
	"""
	Similar to escape(), except that it doesn't operate on pre-escaped strings.
	"""
	if isinstance(html, SafeData):
	return html
	else:
	return escape(html)

	def linebreaks(value, autoescape=False):
	"""Converts newlines into <p> and <br />s."""
	value = normalize_newlines(value)
	paras = re.split('\n{2,}', value)
	if autoescape:
	paras = [u'<p>%s</p>' % escape(p).replace('\n', '<br />') for p in paras]
	else:
	paras = [u'<p>%s</p>' % p.replace('\n', '<br />') for p in paras]
	return u'\n\n'.join(paras)
	linebreaks = allow_lazy(linebreaks, unicode)

	def strip_tags(value):
	"""Returns the given HTML with all tags stripped."""
	return re.sub(r'<[^>]*?>', '', force_unicode(value))
	strip_tags = allow_lazy(strip_tags)

	def strip_spaces_between_tags(value):
	"""Returns the given HTML with spaces between tags removed."""
	return re.sub(r'>\s+<', '><', force_unicode(value))
	strip_spaces_between_tags = allow_lazy(strip_spaces_between_tags, unicode)

	def strip_entities(value):
	"""Returns the given HTML with all entities (&something;) stripped."""
	return re.sub(r'&(?:\w+\|#\d+);', '', force_unicode(value))
	strip_entities = allow_lazy(strip_entities, unicode)

	def fix_ampersands(value):
	"""Returns the given HTML with all unencoded ampersands encoded correctly."""
	return unencoded_ampersands_re.sub('&', force_unicode(value))
	fix_ampersands = allow_lazy(fix_ampersands, unicode)

	def smart_urlquote(url):
	"Quotes a URL if it isn't already quoted."
	# Handle IDN before quoting.
	scheme, netloc, path, query, fragment = urlparse.urlsplit(url)
	try:
	netloc = netloc.encode('idna') # IDN -> ACE
	except UnicodeError: # invalid domain part
	pass
	else:
	url = urlparse.urlunsplit((scheme, netloc, path, query, fragment))

	# An URL is considered unquoted if it contains no % characters or
	# contains a % not followed by two hexadecimal digits. See #9655.
	if '%' not in url or unquoted_percents_re.search(url):
	# See http://bugs.python.org/issue2637
	url = urllib.quote(smart_str(url), safe='!*\'();:@&=+$,/?#[]~')

	return force_unicode(url)

	def urlize(text, trim_url_limit=None, nofollow=False, autoescape=False):
	"""
	Converts any URLs in text into clickable links.

	Works on http://, https://, www. links, and also on links ending in one of
	the original seven gTLDs (.com, .edu, .gov, .int, .mil, .net, and .org).
	Links can have trailing punctuation (periods, commas, close-parens) and
	leading punctuation (opening parens) and it'll still do the right thing.

	If trim_url_limit is not None, the URLs in link text longer than this limit
	will truncated to trim_url_limit-3 characters and appended with an elipsis.

	If nofollow is True, the URLs in link text will get a rel="nofollow"
	attribute.

	If autoescape is True, the link text and URLs will get autoescaped.
	"""
	trim_url = lambda x, limit=trim_url_limit: limit is not None and (len(x) > limit and ('%s...' % x[:max(0, limit - 3)])) or x
	safe_input = isinstance(text, SafeData)
	words = word_split_re.split(force_unicode(text))
	for i, word in enumerate(words):
	match = None
	if '.' in word or '@' in word or ':' in word:
	# Deal with punctuation.
	lead, middle, trail = '', word, ''
	for punctuation in TRAILING_PUNCTUATION:
	if middle.endswith(punctuation):
	middle = middle[:-len(punctuation)]
	trail = punctuation + trail
	for opening, closing in WRAPPING_PUNCTUATION:
	if middle.startswith(opening):
	middle = middle[len(opening):]
	lead = lead + opening
	# Keep parentheses at the end only if they're balanced.
	if (middle.endswith(closing)
	and middle.count(closing) == middle.count(opening) + 1):
	middle = middle[:-len(closing)]
	trail = closing + trail

	# Make URL we want to point to.
	url = None
	nofollow_attr = ' rel="nofollow"' if nofollow else ''
	if simple_url_re.match(middle):
	url = smart_urlquote(middle)
	elif simple_url_2_re.match(middle):
	url = smart_urlquote('http://%s' % middle)
	elif not ':' in middle and simple_email_re.match(middle):
	local, domain = middle.rsplit('@', 1)
	try:
	domain = domain.encode('idna')
	except UnicodeError:
	continue
	url = 'mailto:%s@%s' % (local, domain)
	nofollow_attr = ''

	# Make link.
	if url:
	trimmed = trim_url(middle)
	if autoescape and not safe_input:
	lead, trail = escape(lead), escape(trail)
	url, trimmed = escape(url), escape(trimmed)
	middle = '<a href="%s"%s>%s</a>' % (url, nofollow_attr, trimmed)
	words[i] = mark_safe('%s%s%s' % (lead, middle, trail))
	else:
	if safe_input:
	words[i] = mark_safe(word)
	elif autoescape:
	words[i] = escape(word)
	elif safe_input:
	words[i] = mark_safe(word)
	elif autoescape:
	words[i] = escape(word)
	return u''.join(words)
	urlize = allow_lazy(urlize, unicode)

	def clean_html(text):
	"""
	Clean the given HTML. Specifically, do the following:
	* Convert <b> and <i> to <strong> and <em>.
	* Encode all ampersands correctly.
	* Remove all "target" attributes from <a> tags.
	* Remove extraneous HTML, such as presentational tags that open and
	immediately close and <br clear="all">.
	* Convert hard-coded bullets into HTML unordered lists.
	* Remove stuff like "<p>  </p>", but only if it's at the
	bottom of the text.
	"""
	from django.utils.text import normalize_newlines
	text = normalize_newlines(force_unicode(text))
	text = re.sub(r'<(/?)\sb\s>', '<\\1strong>', text)
	text = re.sub(r'<(/?)\si\s>', '<\\1em>', text)
	text = fix_ampersands(text)
	# Remove all target="" attributes from <a> tags.
	text = link_target_attribute_re.sub('\\1', text)
	# Trim stupid HTML such as <br clear="all">.
	text = html_gunk_re.sub('', text)
	# Convert hard-coded bullets into HTML unordered lists.
	def replace_p_tags(match):
	s = match.group().replace(u'</p>', u'</li>')
	for d in DOTS:
	s = s.replace(u'<p>%s' % d, u'<li>')
	return u'<ul>\n%s\n</ul>' % s
	text = hard_coded_bullets_re.sub(replace_p_tags, text)
	# Remove stuff like "<p>  </p>", but only if it's at the bottom
	# of the text.
	text = trailing_empty_content_re.sub(u'', text)
	return text
	clean_html = allow_lazy(clean_html, unicode)