openmedialibrary_platform/Shared/lib/python3.4/site-packages/html5lib/serializer/htmlserializer.py
2014-09-30 21:25:01 +02:00

320 lines
13 KiB
Python

from __future__ import absolute_import, division, unicode_literals
from six import text_type
import gettext
_ = gettext.gettext
try:
from functools import reduce
except ImportError:
pass
from ..constants import voidElements, booleanAttributes, spaceCharacters
from ..constants import rcdataElements, entities, xmlEntities
from .. import utils
from xml.sax.saxutils import escape
spaceCharacters = "".join(spaceCharacters)
try:
from codecs import register_error, xmlcharrefreplace_errors
except ImportError:
unicode_encode_errors = "strict"
else:
unicode_encode_errors = "htmlentityreplace"
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 not v 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(unicode_encode_errors, htmlentityreplace_errors)
del register_error
class HTMLSerializer(object):
# attribute quoting options
quote_attr_values = False
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=True|False
Whether to quote attribute values that don't require quoting
per HTML5 parsing rules.
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 &lt; &gt; &amp; &quot; &apos;
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
"""
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, unicode_encode_errors)
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):
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)
# 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)
# Alphabetical attributes must be last, as other filters
# could add attributes and alter the order
if self.alphabetical_attributes:
from ..filters.alphabeticalattributes 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_namespace, 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 or not v:
quote_attr = True
else:
quote_attr = reduce(lambda x, y: x or (y in v),
spaceCharacters + ">\"'=", False)
v = v.replace("&", "&amp;")
if self.escape_lt_in_attrs:
v = v.replace("<", "&lt;")
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("'", "&#39;")
else:
v = v.replace('"', "&quot;")
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 not key 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
def SerializeError(Exception):
"""Error in serialized tree"""
pass