from __future__ import absolute_import, division, unicode_literals
from six import text_type
import re
from codecs import register_error, xmlcharrefreplace_errors
from .constants import voidElements, booleanAttributes, spaceCharacters
from .constants import rcdataElements, entities, xmlEntities
from . import treewalkers, _utils
from xml.sax.saxutils import escape
_quoteAttributeSpecChars = "".join(spaceCharacters) + "\"'=`"
_quoteAttributeSpec = re.compile("[" + _quoteAttributeSpecChars + "]")
_quoteAttributeLegacy = re.compile("[" + _quoteAttributeSpecChars +
"\x00\x01\x02\x03\x04\x05\x06\x07\x08\t\n"
"\x0b\x0c\r\x0e\x0f\x10\x11\x12\x13\x14\x15"
"\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f"
"\x20\x2f\x60\xa0\u1680\u180e\u180f\u2000"
"\u2001\u2002\u2003\u2004\u2005\u2006\u2007"
"\u2008\u2009\u200a\u2028\u2029\u202f\u205f"
"\u3000]")
_encode_entity_map = {}
_is_ucs4 = len("\U0010FFFF") == 1
for k, v in list(entities.items()):
# skip multi-character entities
if ((_is_ucs4 and len(v) > 1) or
(not _is_ucs4 and len(v) > 2)):
continue
if v != "&":
if len(v) == 2:
v = _utils.surrogatePairToCodepoint(v)
else:
v = ord(v)
if v not in _encode_entity_map or k.islower():
# prefer < over < and similarly for &, >, etc.
_encode_entity_map[v] = k
def htmlentityreplace_errors(exc):
if isinstance(exc, (UnicodeEncodeError, UnicodeTranslateError)):
res = []
codepoints = []
skip = False
for i, c in enumerate(exc.object[exc.start:exc.end]):
if skip:
skip = False
continue
index = i + exc.start
if _utils.isSurrogatePair(exc.object[index:min([exc.end, index + 2])]):
codepoint = _utils.surrogatePairToCodepoint(exc.object[index:index + 2])
skip = True
else:
codepoint = ord(c)
codepoints.append(codepoint)
for cp in codepoints:
e = _encode_entity_map.get(cp)
if e:
res.append("&")
res.append(e)
if not e.endswith(";"):
res.append(";")
else:
res.append("&#x%s;" % (hex(cp)[2:]))
return ("".join(res), exc.end)
else:
return xmlcharrefreplace_errors(exc)
register_error("htmlentityreplace", htmlentityreplace_errors)
def serialize(input, tree="etree", encoding=None, **serializer_opts):
# XXX: Should we cache this?
walker = treewalkers.getTreeWalker(tree)
s = HTMLSerializer(**serializer_opts)
return s.render(walker(input), encoding)
class HTMLSerializer(object):
# attribute quoting options
quote_attr_values = "legacy" # be secure by default
quote_char = '"'
use_best_quote_char = True
# tag syntax options
omit_optional_tags = True
minimize_boolean_attributes = True
use_trailing_solidus = False
space_before_trailing_solidus = True
# escaping options
escape_lt_in_attrs = False
escape_rcdata = False
resolve_entities = True
# miscellaneous options
alphabetical_attributes = False
inject_meta_charset = True
strip_whitespace = False
sanitize = False
options = ("quote_attr_values", "quote_char", "use_best_quote_char",
"omit_optional_tags", "minimize_boolean_attributes",
"use_trailing_solidus", "space_before_trailing_solidus",
"escape_lt_in_attrs", "escape_rcdata", "resolve_entities",
"alphabetical_attributes", "inject_meta_charset",
"strip_whitespace", "sanitize")
def __init__(self, **kwargs):
"""Initialize HTMLSerializer.
Keyword options (default given first unless specified) include:
inject_meta_charset=True|False
Whether it insert a meta element to define the character set of the
document.
quote_attr_values="legacy"|"spec"|"always"
Whether to quote attribute values that don't require quoting
per legacy browser behaviour, when required by the standard, or always.
quote_char=u'"'|u"'"
Use given quote character for attribute quoting. Default is to
use double quote unless attribute value contains a double quote,
in which case single quotes are used instead.
escape_lt_in_attrs=False|True
Whether to escape < in attribute values.
escape_rcdata=False|True
Whether to escape characters that need to be escaped within normal
elements within rcdata elements such as style.
resolve_entities=True|False
Whether to resolve named character entities that appear in the
source tree. The XML predefined entities < > & " '
are unaffected by this setting.
strip_whitespace=False|True
Whether to remove semantically meaningless whitespace. (This
compresses all whitespace to a single space except within pre.)
minimize_boolean_attributes=True|False
Shortens boolean attributes to give just the attribute value,
for example becomes .
use_trailing_solidus=False|True
Includes a close-tag slash at the end of the start tag of void
elements (empty elements whose end tag is forbidden). E.g. .
space_before_trailing_solidus=True|False
Places a space immediately before the closing slash in a tag
using a trailing solidus. E.g. . Requires use_trailing_solidus.
sanitize=False|True
Strip all unsafe or unknown constructs from output.
See `html5lib user documentation`_
omit_optional_tags=True|False
Omit start/end tags that are optional.
alphabetical_attributes=False|True
Reorder attributes to be in alphabetical order.
.. _html5lib user documentation: http://code.google.com/p/html5lib/wiki/UserDocumentation
"""
unexpected_args = frozenset(kwargs) - frozenset(self.options)
if len(unexpected_args) > 0:
raise TypeError("__init__() got an unexpected keyword argument '%s'" % next(iter(unexpected_args)))
if 'quote_char' in kwargs:
self.use_best_quote_char = False
for attr in self.options:
setattr(self, attr, kwargs.get(attr, getattr(self, attr)))
self.errors = []
self.strict = False
def encode(self, string):
assert(isinstance(string, text_type))
if self.encoding:
return string.encode(self.encoding, "htmlentityreplace")
else:
return string
def encodeStrict(self, string):
assert(isinstance(string, text_type))
if self.encoding:
return string.encode(self.encoding, "strict")
else:
return string
def serialize(self, treewalker, encoding=None):
# pylint:disable=too-many-nested-blocks
self.encoding = encoding
in_cdata = False
self.errors = []
if encoding and self.inject_meta_charset:
from .filters.inject_meta_charset import Filter
treewalker = Filter(treewalker, encoding)
# Alphabetical attributes is here under the assumption that none of
# the later filters add or change order of attributes; it needs to be
# before the sanitizer so escaped elements come out correctly
if self.alphabetical_attributes:
from .filters.alphabeticalattributes import Filter
treewalker = Filter(treewalker)
# WhitespaceFilter should be used before OptionalTagFilter
# for maximum efficiently of this latter filter
if self.strip_whitespace:
from .filters.whitespace import Filter
treewalker = Filter(treewalker)
if self.sanitize:
from .filters.sanitizer import Filter
treewalker = Filter(treewalker)
if self.omit_optional_tags:
from .filters.optionaltags import Filter
treewalker = Filter(treewalker)
for token in treewalker:
type = token["type"]
if type == "Doctype":
doctype = ""
yield self.encodeStrict(doctype)
elif type in ("Characters", "SpaceCharacters"):
if type == "SpaceCharacters" or in_cdata:
if in_cdata and token["data"].find("