mirror of https://github.com/python/cpython
447 lines
15 KiB
Python
447 lines
15 KiB
Python
"""
|
|
SAX driver for the pyexpat C module. This driver works with
|
|
pyexpat.__version__ == '2.22'.
|
|
"""
|
|
|
|
version = "0.20"
|
|
|
|
from xml.sax._exceptions import *
|
|
from xml.sax.handler import feature_validation, feature_namespaces
|
|
from xml.sax.handler import feature_namespace_prefixes
|
|
from xml.sax.handler import feature_external_ges, feature_external_pes
|
|
from xml.sax.handler import feature_string_interning
|
|
from xml.sax.handler import property_xml_string, property_interning_dict
|
|
|
|
# xml.parsers.expat does not raise ImportError in Jython
|
|
import sys
|
|
if sys.platform[:4] == "java":
|
|
raise SAXReaderNotAvailable("expat not available in Java", None)
|
|
del sys
|
|
|
|
try:
|
|
from xml.parsers import expat
|
|
except ImportError:
|
|
raise SAXReaderNotAvailable("expat not supported", None)
|
|
else:
|
|
if not hasattr(expat, "ParserCreate"):
|
|
raise SAXReaderNotAvailable("expat not supported", None)
|
|
from xml.sax import xmlreader, saxutils, handler
|
|
|
|
AttributesImpl = xmlreader.AttributesImpl
|
|
AttributesNSImpl = xmlreader.AttributesNSImpl
|
|
|
|
# If we're using a sufficiently recent version of Python, we can use
|
|
# weak references to avoid cycles between the parser and content
|
|
# handler, otherwise we'll just have to pretend.
|
|
try:
|
|
import _weakref
|
|
except ImportError:
|
|
def _mkproxy(o):
|
|
return o
|
|
else:
|
|
import weakref
|
|
_mkproxy = weakref.proxy
|
|
del weakref, _weakref
|
|
|
|
class _ClosedParser:
|
|
pass
|
|
|
|
# --- ExpatLocator
|
|
|
|
class ExpatLocator(xmlreader.Locator):
|
|
"""Locator for use with the ExpatParser class.
|
|
|
|
This uses a weak reference to the parser object to avoid creating
|
|
a circular reference between the parser and the content handler.
|
|
"""
|
|
def __init__(self, parser):
|
|
self._ref = _mkproxy(parser)
|
|
|
|
def getColumnNumber(self):
|
|
parser = self._ref
|
|
if parser._parser is None:
|
|
return None
|
|
return parser._parser.ErrorColumnNumber
|
|
|
|
def getLineNumber(self):
|
|
parser = self._ref
|
|
if parser._parser is None:
|
|
return 1
|
|
return parser._parser.ErrorLineNumber
|
|
|
|
def getPublicId(self):
|
|
parser = self._ref
|
|
if parser is None:
|
|
return None
|
|
return parser._source.getPublicId()
|
|
|
|
def getSystemId(self):
|
|
parser = self._ref
|
|
if parser is None:
|
|
return None
|
|
return parser._source.getSystemId()
|
|
|
|
|
|
# --- ExpatParser
|
|
|
|
class ExpatParser(xmlreader.IncrementalParser, xmlreader.Locator):
|
|
"""SAX driver for the pyexpat C module."""
|
|
|
|
def __init__(self, namespaceHandling=0, bufsize=2**16-20):
|
|
xmlreader.IncrementalParser.__init__(self, bufsize)
|
|
self._source = xmlreader.InputSource()
|
|
self._parser = None
|
|
self._namespaces = namespaceHandling
|
|
self._lex_handler_prop = None
|
|
self._parsing = 0
|
|
self._entity_stack = []
|
|
self._external_ges = 0
|
|
self._interning = None
|
|
|
|
# XMLReader methods
|
|
|
|
def parse(self, source):
|
|
"Parse an XML document from a URL or an InputSource."
|
|
source = saxutils.prepare_input_source(source)
|
|
|
|
self._source = source
|
|
try:
|
|
self.reset()
|
|
self._cont_handler.setDocumentLocator(ExpatLocator(self))
|
|
xmlreader.IncrementalParser.parse(self, source)
|
|
except:
|
|
# bpo-30264: Close the source on error to not leak resources:
|
|
# xml.sax.parse() doesn't give access to the underlying parser
|
|
# to the caller
|
|
self._close_source()
|
|
raise
|
|
|
|
def prepareParser(self, source):
|
|
if source.getSystemId() is not None:
|
|
self._parser.SetBase(source.getSystemId())
|
|
|
|
# Redefined setContentHandler to allow changing handlers during parsing
|
|
|
|
def setContentHandler(self, handler):
|
|
xmlreader.IncrementalParser.setContentHandler(self, handler)
|
|
if self._parsing:
|
|
self._reset_cont_handler()
|
|
|
|
def getFeature(self, name):
|
|
if name == feature_namespaces:
|
|
return self._namespaces
|
|
elif name == feature_string_interning:
|
|
return self._interning is not None
|
|
elif name in (feature_validation, feature_external_pes,
|
|
feature_namespace_prefixes):
|
|
return 0
|
|
elif name == feature_external_ges:
|
|
return self._external_ges
|
|
raise SAXNotRecognizedException("Feature '%s' not recognized" % name)
|
|
|
|
def setFeature(self, name, state):
|
|
if self._parsing:
|
|
raise SAXNotSupportedException("Cannot set features while parsing")
|
|
|
|
if name == feature_namespaces:
|
|
self._namespaces = state
|
|
elif name == feature_external_ges:
|
|
self._external_ges = state
|
|
elif name == feature_string_interning:
|
|
if state:
|
|
if self._interning is None:
|
|
self._interning = {}
|
|
else:
|
|
self._interning = None
|
|
elif name == feature_validation:
|
|
if state:
|
|
raise SAXNotSupportedException(
|
|
"expat does not support validation")
|
|
elif name == feature_external_pes:
|
|
if state:
|
|
raise SAXNotSupportedException(
|
|
"expat does not read external parameter entities")
|
|
elif name == feature_namespace_prefixes:
|
|
if state:
|
|
raise SAXNotSupportedException(
|
|
"expat does not report namespace prefixes")
|
|
else:
|
|
raise SAXNotRecognizedException(
|
|
"Feature '%s' not recognized" % name)
|
|
|
|
def getProperty(self, name):
|
|
if name == handler.property_lexical_handler:
|
|
return self._lex_handler_prop
|
|
elif name == property_interning_dict:
|
|
return self._interning
|
|
elif name == property_xml_string:
|
|
if self._parser:
|
|
if hasattr(self._parser, "GetInputContext"):
|
|
return self._parser.GetInputContext()
|
|
else:
|
|
raise SAXNotRecognizedException(
|
|
"This version of expat does not support getting"
|
|
" the XML string")
|
|
else:
|
|
raise SAXNotSupportedException(
|
|
"XML string cannot be returned when not parsing")
|
|
raise SAXNotRecognizedException("Property '%s' not recognized" % name)
|
|
|
|
def setProperty(self, name, value):
|
|
if name == handler.property_lexical_handler:
|
|
self._lex_handler_prop = value
|
|
if self._parsing:
|
|
self._reset_lex_handler_prop()
|
|
elif name == property_interning_dict:
|
|
self._interning = value
|
|
elif name == property_xml_string:
|
|
raise SAXNotSupportedException("Property '%s' cannot be set" %
|
|
name)
|
|
else:
|
|
raise SAXNotRecognizedException("Property '%s' not recognized" %
|
|
name)
|
|
|
|
# IncrementalParser methods
|
|
|
|
def feed(self, data, isFinal = 0):
|
|
if not self._parsing:
|
|
self.reset()
|
|
self._parsing = 1
|
|
self._cont_handler.startDocument()
|
|
|
|
try:
|
|
# The isFinal parameter is internal to the expat reader.
|
|
# If it is set to true, expat will check validity of the entire
|
|
# document. When feeding chunks, they are not normally final -
|
|
# except when invoked from close.
|
|
self._parser.Parse(data, isFinal)
|
|
except expat.error as e:
|
|
exc = SAXParseException(expat.ErrorString(e.code), e, self)
|
|
# FIXME: when to invoke error()?
|
|
self._err_handler.fatalError(exc)
|
|
|
|
def _close_source(self):
|
|
source = self._source
|
|
try:
|
|
file = source.getCharacterStream()
|
|
if file is not None:
|
|
file.close()
|
|
finally:
|
|
file = source.getByteStream()
|
|
if file is not None:
|
|
file.close()
|
|
|
|
def close(self):
|
|
if (self._entity_stack or self._parser is None or
|
|
isinstance(self._parser, _ClosedParser)):
|
|
# If we are completing an external entity, do nothing here
|
|
return
|
|
try:
|
|
self.feed("", isFinal = 1)
|
|
self._cont_handler.endDocument()
|
|
self._parsing = 0
|
|
# break cycle created by expat handlers pointing to our methods
|
|
self._parser = None
|
|
finally:
|
|
self._parsing = 0
|
|
if self._parser is not None:
|
|
# Keep ErrorColumnNumber and ErrorLineNumber after closing.
|
|
parser = _ClosedParser()
|
|
parser.ErrorColumnNumber = self._parser.ErrorColumnNumber
|
|
parser.ErrorLineNumber = self._parser.ErrorLineNumber
|
|
self._parser = parser
|
|
self._close_source()
|
|
|
|
def _reset_cont_handler(self):
|
|
self._parser.ProcessingInstructionHandler = \
|
|
self._cont_handler.processingInstruction
|
|
self._parser.CharacterDataHandler = self._cont_handler.characters
|
|
|
|
def _reset_lex_handler_prop(self):
|
|
lex = self._lex_handler_prop
|
|
parser = self._parser
|
|
if lex is None:
|
|
parser.CommentHandler = None
|
|
parser.StartCdataSectionHandler = None
|
|
parser.EndCdataSectionHandler = None
|
|
parser.StartDoctypeDeclHandler = None
|
|
parser.EndDoctypeDeclHandler = None
|
|
else:
|
|
parser.CommentHandler = lex.comment
|
|
parser.StartCdataSectionHandler = lex.startCDATA
|
|
parser.EndCdataSectionHandler = lex.endCDATA
|
|
parser.StartDoctypeDeclHandler = self.start_doctype_decl
|
|
parser.EndDoctypeDeclHandler = lex.endDTD
|
|
|
|
def reset(self):
|
|
if self._namespaces:
|
|
self._parser = expat.ParserCreate(self._source.getEncoding(), " ",
|
|
intern=self._interning)
|
|
self._parser.namespace_prefixes = 1
|
|
self._parser.StartElementHandler = self.start_element_ns
|
|
self._parser.EndElementHandler = self.end_element_ns
|
|
else:
|
|
self._parser = expat.ParserCreate(self._source.getEncoding(),
|
|
intern = self._interning)
|
|
self._parser.StartElementHandler = self.start_element
|
|
self._parser.EndElementHandler = self.end_element
|
|
|
|
self._reset_cont_handler()
|
|
self._parser.UnparsedEntityDeclHandler = self.unparsed_entity_decl
|
|
self._parser.NotationDeclHandler = self.notation_decl
|
|
self._parser.StartNamespaceDeclHandler = self.start_namespace_decl
|
|
self._parser.EndNamespaceDeclHandler = self.end_namespace_decl
|
|
|
|
self._decl_handler_prop = None
|
|
if self._lex_handler_prop:
|
|
self._reset_lex_handler_prop()
|
|
# self._parser.DefaultHandler =
|
|
# self._parser.DefaultHandlerExpand =
|
|
# self._parser.NotStandaloneHandler =
|
|
self._parser.ExternalEntityRefHandler = self.external_entity_ref
|
|
try:
|
|
self._parser.SkippedEntityHandler = self.skipped_entity_handler
|
|
except AttributeError:
|
|
# This pyexpat does not support SkippedEntity
|
|
pass
|
|
self._parser.SetParamEntityParsing(
|
|
expat.XML_PARAM_ENTITY_PARSING_UNLESS_STANDALONE)
|
|
|
|
self._parsing = 0
|
|
self._entity_stack = []
|
|
|
|
# Locator methods
|
|
|
|
def getColumnNumber(self):
|
|
if self._parser is None:
|
|
return None
|
|
return self._parser.ErrorColumnNumber
|
|
|
|
def getLineNumber(self):
|
|
if self._parser is None:
|
|
return 1
|
|
return self._parser.ErrorLineNumber
|
|
|
|
def getPublicId(self):
|
|
return self._source.getPublicId()
|
|
|
|
def getSystemId(self):
|
|
return self._source.getSystemId()
|
|
|
|
# event handlers
|
|
def start_element(self, name, attrs):
|
|
self._cont_handler.startElement(name, AttributesImpl(attrs))
|
|
|
|
def end_element(self, name):
|
|
self._cont_handler.endElement(name)
|
|
|
|
def start_element_ns(self, name, attrs):
|
|
pair = name.split()
|
|
if len(pair) == 1:
|
|
# no namespace
|
|
pair = (None, name)
|
|
elif len(pair) == 3:
|
|
pair = pair[0], pair[1]
|
|
else:
|
|
# default namespace
|
|
pair = tuple(pair)
|
|
|
|
newattrs = {}
|
|
qnames = {}
|
|
for (aname, value) in attrs.items():
|
|
parts = aname.split()
|
|
length = len(parts)
|
|
if length == 1:
|
|
# no namespace
|
|
qname = aname
|
|
apair = (None, aname)
|
|
elif length == 3:
|
|
qname = "%s:%s" % (parts[2], parts[1])
|
|
apair = parts[0], parts[1]
|
|
else:
|
|
# default namespace
|
|
qname = parts[1]
|
|
apair = tuple(parts)
|
|
|
|
newattrs[apair] = value
|
|
qnames[apair] = qname
|
|
|
|
self._cont_handler.startElementNS(pair, None,
|
|
AttributesNSImpl(newattrs, qnames))
|
|
|
|
def end_element_ns(self, name):
|
|
pair = name.split()
|
|
if len(pair) == 1:
|
|
pair = (None, name)
|
|
elif len(pair) == 3:
|
|
pair = pair[0], pair[1]
|
|
else:
|
|
pair = tuple(pair)
|
|
|
|
self._cont_handler.endElementNS(pair, None)
|
|
|
|
# this is not used (call directly to ContentHandler)
|
|
def processing_instruction(self, target, data):
|
|
self._cont_handler.processingInstruction(target, data)
|
|
|
|
# this is not used (call directly to ContentHandler)
|
|
def character_data(self, data):
|
|
self._cont_handler.characters(data)
|
|
|
|
def start_namespace_decl(self, prefix, uri):
|
|
self._cont_handler.startPrefixMapping(prefix, uri)
|
|
|
|
def end_namespace_decl(self, prefix):
|
|
self._cont_handler.endPrefixMapping(prefix)
|
|
|
|
def start_doctype_decl(self, name, sysid, pubid, has_internal_subset):
|
|
self._lex_handler_prop.startDTD(name, pubid, sysid)
|
|
|
|
def unparsed_entity_decl(self, name, base, sysid, pubid, notation_name):
|
|
self._dtd_handler.unparsedEntityDecl(name, pubid, sysid, notation_name)
|
|
|
|
def notation_decl(self, name, base, sysid, pubid):
|
|
self._dtd_handler.notationDecl(name, pubid, sysid)
|
|
|
|
def external_entity_ref(self, context, base, sysid, pubid):
|
|
if not self._external_ges:
|
|
return 1
|
|
|
|
source = self._ent_handler.resolveEntity(pubid, sysid)
|
|
source = saxutils.prepare_input_source(source,
|
|
self._source.getSystemId() or
|
|
"")
|
|
|
|
self._entity_stack.append((self._parser, self._source))
|
|
self._parser = self._parser.ExternalEntityParserCreate(context)
|
|
self._source = source
|
|
|
|
try:
|
|
xmlreader.IncrementalParser.parse(self, source)
|
|
except:
|
|
return 0 # FIXME: save error info here?
|
|
|
|
(self._parser, self._source) = self._entity_stack[-1]
|
|
del self._entity_stack[-1]
|
|
return 1
|
|
|
|
def skipped_entity_handler(self, name, is_pe):
|
|
if is_pe:
|
|
# The SAX spec requires to report skipped PEs with a '%'
|
|
name = '%'+name
|
|
self._cont_handler.skippedEntity(name)
|
|
|
|
# ---
|
|
|
|
def create_parser(*args, **kwargs):
|
|
return ExpatParser(*args, **kwargs)
|
|
|
|
# ---
|
|
|
|
if __name__ == "__main__":
|
|
import xml.sax.saxutils
|
|
p = create_parser()
|
|
p.setContentHandler(xml.sax.saxutils.XMLGenerator())
|
|
p.setErrorHandler(xml.sax.ErrorHandler())
|
|
p.parse("http://www.ibiblio.org/xml/examples/shakespeare/hamlet.xml")
|