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from __future__ import absolute_import, division, unicode_literals
from pip._vendor.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 <input disabled="disabled"> becomes <input disabled>.
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. <hr/>.
space_before_trailing_solidus=True|False
Places a space immediately before the closing slash in a tag
using a trailing solidus. E.g. <hr />. 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 = "<!DOCTYPE %s" % token["name"]
if token["publicId"]:
doctype += ' PUBLIC "%s"' % token["publicId"]
elif token["systemId"]:
doctype += " SYSTEM"
if token["systemId"]:
if token["systemId"].find('"') >= 0:
if token["systemId"].find("'") >= 0:
self.serializeError("System identifer contains both single and double quote characters")
quote_char = "'"
else:
quote_char = '"'
doctype += " %s%s%s" % (quote_char, token["systemId"], quote_char)
doctype += ">"
yield self.encodeStrict(doctype)
elif type in ("Characters", "SpaceCharacters"):
if type == "SpaceCharacters" or in_cdata:
if in_cdata and token["data"].find("</") >= 0:
self.serializeError("Unexpected </ in CDATA")
yield self.encode(token["data"])
else:
yield self.encode(escape(token["data"]))
elif type in ("StartTag", "EmptyTag"):
name = token["name"]
yield self.encodeStrict("<%s" % name)
if name in rcdataElements and not self.escape_rcdata:
in_cdata = True
elif in_cdata:
self.serializeError("Unexpected child element of a CDATA element")
for (_, attr_name), attr_value in token["data"].items():
# TODO: Add namespace support here
k = attr_name
v = attr_value
yield self.encodeStrict(' ')
yield self.encodeStrict(k)
if not self.minimize_boolean_attributes or \
(k not in booleanAttributes.get(name, tuple()) and
k not in booleanAttributes.get("", tuple())):
yield self.encodeStrict("=")
if self.quote_attr_values == "always" or len(v) == 0:
quote_attr = True
elif self.quote_attr_values == "spec":
quote_attr = _quoteAttributeSpec.search(v) is not None
elif self.quote_attr_values == "legacy":
quote_attr = _quoteAttributeLegacy.search(v) is not None
else:
raise ValueError("quote_attr_values must be one of: "
"'always', 'spec', or 'legacy'")
v = v.replace("&", "&")
if self.escape_lt_in_attrs:
v = v.replace("<", "<")
if quote_attr:
quote_char = self.quote_char
if self.use_best_quote_char:
if "'" in v and '"' not in v:
quote_char = '"'
elif '"' in v and "'" not in v:
quote_char = "'"
if quote_char == "'":
v = v.replace("'", "'")
else:
v = v.replace('"', """)
yield self.encodeStrict(quote_char)
yield self.encode(v)
yield self.encodeStrict(quote_char)
else:
yield self.encode(v)
if name in voidElements and self.use_trailing_solidus:
if self.space_before_trailing_solidus:
yield self.encodeStrict(" /")
else:
yield self.encodeStrict("/")
yield self.encode(">")
elif type == "EndTag":
name = token["name"]
if name in rcdataElements:
in_cdata = False
elif in_cdata:
self.serializeError("Unexpected child element of a CDATA element")
yield self.encodeStrict("</%s>" % name)
elif type == "Comment":
data = token["data"]
if data.find("--") >= 0:
self.serializeError("Comment contains --")
yield self.encodeStrict("<!--%s-->" % token["data"])
elif type == "Entity":
name = token["name"]
key = name + ";"
if key not in entities:
self.serializeError("Entity %s not recognized" % name)
if self.resolve_entities and key not in xmlEntities:
data = entities[key]
else:
data = "&%s;" % name
yield self.encodeStrict(data)
else:
self.serializeError(token["data"])
def render(self, treewalker, encoding=None):
if encoding:
return b"".join(list(self.serialize(treewalker, encoding)))
else:
return "".join(list(self.serialize(treewalker)))
def serializeError(self, data="XXX ERROR MESSAGE NEEDED"):
# XXX The idea is to make data mandatory.
self.errors.append(data)
if self.strict:
raise SerializeError
class SerializeError(Exception):
"""Error in serialized tree"""
pass
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