')
'html "test" & <brothers>'
'''
if not isinstance(html, str):
html = str(html)
return html.replace('&', '&').replace('<', '<').replace('>', '>').replace('"', '"').replace("'", ''')
def linebreaks(value):
'''
Converts newlines into and
'''
value = re.sub(r'\r\n|\r|\n', '\n', value) # normalize newlines
paras = re.split('\n{2,}', value)
paras = ['
%s
' % p.strip().replace('\n', '
') for p in paras]
return '\n\n'.join(paras)
def strip_tags(value):
"""
Returns the given HTML with all tags stripped
>>> strip_tags('some title
')
'some title asdfasdf'
"""
return re.sub(r'<[^>]*?>', '', value)
stripTags = strip_tags
def strip_spaces_between_tags(value):
"Returns the given HTML with spaces between tags normalized to a single space"
return re.sub(r'>\s+<', '> <', value)
def strip_entities(value):
"Returns the given HTML with all entities (&something;) stripped"
return re.sub(r'&(?:\w+|#\d);', '', value)
def fix_ampersands(value):
"Returns the given HTML with all unencoded ampersands encoded correctly"
return unencoded_ampersands_re.sub('&', value)
def add_links(text, trim_url_limit=None, nofollow=False):
"""
Converts any URLs in text into clickable links. Works on http://, https:// and
www. links. 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 will be limited to
trim_url_limit characters.
If nofollow is True, the URLs in link text will get a rel="nofollow" attribute.
"""
trim_url = lambda x, limit=trim_url_limit: limit is not None and (x[:limit] + (len(x) >= limit and '...' or '')) or x
words = word_split_re.split(text)
nofollow_attr = nofollow and ' rel="nofollow"' or ''
for i, word in enumerate(words):
match = punctuation_re.match(word)
if match:
lead, middle, trail = match.groups()
if middle.startswith('www.') or ('@' not in middle and not middle.startswith('http://') and
len(middle) > 0 and middle[0] in letters + string.digits and
(middle.endswith('.org') or
middle.endswith('.net') or
middle.endswith('.com'))):
middle = '%s' % (middle, nofollow_attr, trim_url(middle))
if middle.startswith('http://') or middle.startswith('https://'):
middle = '%s' % (middle, nofollow_attr, trim_url(middle))
if '@' in middle and not middle.startswith('www.') and ':' not in middle \
and simple_email_re.match(middle):
middle = '%s' % (middle, middle)
if lead + middle + trail != word:
words[i] = lead + middle + trail
return ''.join(words)
urlize = add_links
def clean_html(text):
"""
Cleans the given HTML. Specifically, it does the following:
* Converts and to and .
* Encodes all ampersands correctly.
* Removes all "target" attributes from tags.
* Removes extraneous HTML, such as presentational tags that open and
immediately close and
.
* Converts hard-coded bullets into HTML unordered lists.
* Removes stuff like "
", but only if it's at the
bottom of the text.
"""
from .text import normalize_newlines
text = normalize_newlines(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 tags.
text = link_target_attribute_re.sub('\\1', text)
# Trim stupid HTML such as
.
text = html_gunk_re.sub('', text)
# Convert hard-coded bullets into HTML unordered lists.
def replace_p_tags(match):
s = match.group().replace('', '')
for d in DOTS:
s = s.replace('%s' % d, '
')
return '' % s
text = hard_coded_bullets_re.sub(replace_p_tags, text)
# Remove stuff like "
", but only if it's at the bottom of the text.
text = trailing_empty_content_re.sub('', text)
return text
# This pattern matches a character entity reference (a decimal numeric
# references, a hexadecimal numeric reference, or a named reference).
charrefpat = re.compile(r'&(#(\d+|x[\da-fA-F]+)|[\w.:-]+);?')
def decode_html(html):
"""
>>> decode_html('me & you and $&%')
'me & you and $&%'
>>> decode_html('€')
'\u20ac'
>>> decode_html('Anniversary of Daoud's Republic')
"Anniversary of Daoud's Republic"
"""
if isinstance(html, bytes):
html = html.decode('utf-8')
uchr = chr
def entitydecode(match, uchr=uchr):
entity = match.group(1)
if entity == '#x80':
return '€'
elif entity.startswith('#x'):
return uchr(int(entity[2:], 16))
elif entity.startswith('#'):
return uchr(int(entity[1:]))
elif entity in name2codepoint:
return uchr(name2codepoint[entity])
elif entity == 'apos':
return "'"
else:
return match.group(0)
return charrefpat.sub(entitydecode, html).replace('\xa0', ' ')
def highlight(text, query, hlClass="hl"):
"""
>>> highlight('me & you and $&%', 'and')
'me & you and $&%'
"""
if query:
text = text.replace('
', '|')
query = re.escape(query).replace(r'\ ', '.')
m = re.compile("(%s)" % query, re.IGNORECASE).findall(text)
for i in m:
text = re.sub(r"(%s)" % re.escape(i).replace(r'\ ', '.'), r'\\1' % hlClass, text)
text = text.replace('|', '
')
return text
def escape_html(value):
'''
>>> escape_html('')
'<script>alert()</script>'
>>> sanitize_html("'foo' < 'bar' && \\"foo\\" > \\"bar\\"")
'\\'foo\\' < \\'bar\\' && "foo" > "bar"'
>>> sanitize_html('foo')
'foo'
>>> sanitize_html('foo')
'foo'
>>> sanitize_html('Anniversary of Daoud's Republic')
"Anniversary of Daoud's Republic"
>>> sanitize_html('')
''
>>> sanitize_html(' ')
' '
>>> sanitize_html(' ') # canonicalised to a space: okay, I suppose
' '
>>> sanitize_html('\u00a0') # also nbsp
' '
'''
if not tags:
valid_url = r'^((https?:\/\/|\/|mailto:).*?)'
tags = [
# inline formatting
{'name': 'b'},
{'name': 'bdi'},
{'name': 'code'},
{'name': 'em'},
{'name': 'i'},
{'name': 'q'},
{'name': 's'},
{'name': 'span'},
{'name': 'strong'},
{'name': 'sub'},
{'name': 'sup'},
{'name': 'u'},
# block formatting
{'name': 'blockquote'},
{'name': 'cite'},
{
'name': 'div',
'optional': ['style'],
'validation': {
'style': '^direction: rtl$'
}
},
{'name': 'h1'},
{'name': 'h2'},
{'name': 'h3'},
{'name': 'h4'},
{'name': 'h5'},
{'name': 'h6'},
{'name': 'p'},
{'name': 'pre'},
# lists
{'name': 'li'},
{'name': 'ol'},
{'name': 'ul'},
# definition lists
{'name': 'dl'},
{'name': 'dt'},
{'name': 'dd'},
# tables
{'name': 'table'},
{'name': 'tbody'},
{'name': 'td'},
{'name': 'tfoot'},
{'name': 'th'},
{'name': 'thead'},
{'name': 'tr'},
# other
{'name': '[]'},
{
'name': 'a',
'required': ['href'],
'optional': ['target'],
'validation': {
'href': valid_url,
'target': '^_blank$',
}
},
{'name': 'br'},
{
'name': 'iframe',
'optional': ['width', 'height'],
'required': ['src'],
'validation': {
'width': r'^\d+$',
'height': r'^\d+$',
'src': valid_url
}
},
{
'name': 'img',
'optional': ['width', 'height'],
'required': ['src'],
'validation': {
'width': r'^\d+$',
'height': r'^\d+$',
'src': valid_url
},
},
{'name': 'figure'},
{'name': 'figcaption'}
]
tag_re = re.compile(r'<(/)?([^\ /]+)(.*?)(/)?>')
attr_re = re.compile(r'([^=\ ]+)="([^"]+)"')
escaped = {}
level = 0
non_closing_tags = ['img', 'br']
required_attributes = {}
validation = {}
valid_attributes = {}
valid_tags = set([tag['name'] for tag in tags if tag['name'] != '[]'])
for tag in tags:
valid_attributes[tag['name']] = tag.get('required', []) \
+ tag.get('optional', []) + global_attributes
required_attributes[tag['name']] = tag.get('required', [])
validation[tag['name']] = tag.get('validation', {})
if '[]' in validation:
html = re.sub(
re.compile(r'\[((https?:\/\/|\/).+?) (.+?)\]', re.IGNORECASE),
'\\3', html)
parts = split_tags(html)
for i, part in enumerate(parts):
is_tag = i % 2
if is_tag:
t = tag_re.findall(part)
if not t:
parts[i] = escape_html(decode_html(part))
continue
closing, name, attributes, end = t[0]
closing = closing != ''
a = attr_re.findall(attributes)
attrs = dict(a)
if not closing and name not in non_closing_tags:
level += 1
if not attrs and attributes or name not in valid_tags:
valid = False
else:
valid = True
for key in set(attrs) - set(valid_attributes[name]):
del attrs[key]
for key in required_attributes[tag['name']]:
if key not in attrs:
valid = False
if valid:
for attr in attrs:
if attr in validation[name]:
if not re.compile(validation[name][attr]).findall(attrs[attr]):
valid = False
break
if valid and closing:
valid = not escaped.get(level)
else:
escaped[level] = not valid
if closing:
level -= 1
if valid:
parts[i] = '<%s%s%s>' % (
('/' if closing else ''),
name,
(' ' + ' '.join(['%s="%s"' % (key, attrs[key]) for key, value in a if key in attrs])
if not closing and attrs else '')
)
else:
parts[i] = escape_html(decode_html(part))
else:
parts[i] = escape_html(decode_html(part))
html = ''.join(parts)
html = add_links(html)
html = html.replace('\n\n', '
')
return sanitize_fragment(html)
def split_tags(string):
tags = []
def collect(match):
tags.append(match.group(0))
return '\0'
strings = re.sub('<[^<>]+>', collect, string).split('\0')
tags.append('')
return [item for sublist in zip(strings, tags) for item in sublist][:-1]
def sanitize_fragment(html):
'''
Ensures that tags are closed (or not, as appropriate), attributes
are quoted, etc. Does not strip potentially-malicious HTML: use
sanitize_html() for that.
>>> sanitize_fragment('')
''
>>> sanitize_fragment('')
''
>>> sanitize_fragment('
')
'
'
>>> sanitize_fragment('foo')
'foo'
>>> sanitize_fragment('')
''
>>> sanitize_fragment(' ')
' '
>>> sanitize_fragment(' ')
'\\xa0'
>>> sanitize_fragment('\\u00a0') # nbsp
'\\xa0'
>>> sanitize_fragment('\\ufeff') # zero-width no-break space
'\\ufeff'
'''
'''
#html5lib reorders arguments, so not usable
import html5lib
return html5lib.parseFragment(html).toxml().decode('utf-8')
'''
if not html.strip():
return html
import lxml.html
try:
body = lxml.html.document_fromstring(html).find('body')
except lxml.etree.ParserError as e:
if e.args and e.args[0] == 'Document is empty':
return html
raise e
html = lxml.html.tostring(body, encoding='utf-8')[6:-7].decode('utf-8')
if html.startswith('') and html.endswith('
'):
html = html[3:-4]
return html