Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 1 | """Facility to use the Expat parser to load a minidom instance |
| 2 | from a string or file. |
| 3 | |
| 4 | This avoids all the overhead of SAX and pulldom to gain performance. |
| 5 | """ |
| 6 | |
| 7 | # Warning! |
| 8 | # |
| 9 | # This module is tightly bound to the implementation details of the |
| 10 | # minidom DOM and can't be used with other DOM implementations. This |
| 11 | # is due, in part, to a lack of appropriate methods in the DOM (there is |
| 12 | # no way to create Entity and Notation nodes via the DOM Level 2 |
| 13 | # interface), and for performance. The later is the cause of some fairly |
| 14 | # cryptic code. |
| 15 | # |
| 16 | # Performance hacks: |
| 17 | # |
| 18 | # - .character_data_handler() has an extra case in which continuing |
| 19 | # data is appended to an existing Text node; this can be a |
| 20 | # speedup since pyexpat can break up character data into multiple |
| 21 | # callbacks even though we set the buffer_text attribute on the |
| 22 | # parser. This also gives us the advantage that we don't need a |
| 23 | # separate normalization pass. |
| 24 | # |
| 25 | # - Determining that a node exists is done using an identity comparison |
| 26 | # with None rather than a truth test; this avoids searching for and |
| 27 | # calling any methods on the node object if it exists. (A rather |
| 28 | # nice speedup is achieved this way as well!) |
| 29 | |
Thomas Wouters | 0e3f591 | 2006-08-11 14:57:12 +0000 | [diff] [blame] | 30 | from xml.dom import xmlbuilder, minidom, Node |
| 31 | from xml.dom import EMPTY_NAMESPACE, EMPTY_PREFIX, XMLNS_NAMESPACE |
| 32 | from xml.parsers import expat |
| 33 | from xml.dom.minidom import _append_child, _set_attribute_node |
| 34 | from xml.dom.NodeFilter import NodeFilter |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 35 | |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 36 | TEXT_NODE = Node.TEXT_NODE |
| 37 | CDATA_SECTION_NODE = Node.CDATA_SECTION_NODE |
| 38 | DOCUMENT_NODE = Node.DOCUMENT_NODE |
| 39 | |
| 40 | FILTER_ACCEPT = xmlbuilder.DOMBuilderFilter.FILTER_ACCEPT |
| 41 | FILTER_REJECT = xmlbuilder.DOMBuilderFilter.FILTER_REJECT |
| 42 | FILTER_SKIP = xmlbuilder.DOMBuilderFilter.FILTER_SKIP |
| 43 | FILTER_INTERRUPT = xmlbuilder.DOMBuilderFilter.FILTER_INTERRUPT |
| 44 | |
| 45 | theDOMImplementation = minidom.getDOMImplementation() |
| 46 | |
| 47 | # Expat typename -> TypeInfo |
| 48 | _typeinfo_map = { |
| 49 | "CDATA": minidom.TypeInfo(None, "cdata"), |
| 50 | "ENUM": minidom.TypeInfo(None, "enumeration"), |
| 51 | "ENTITY": minidom.TypeInfo(None, "entity"), |
| 52 | "ENTITIES": minidom.TypeInfo(None, "entities"), |
| 53 | "ID": minidom.TypeInfo(None, "id"), |
| 54 | "IDREF": minidom.TypeInfo(None, "idref"), |
| 55 | "IDREFS": minidom.TypeInfo(None, "idrefs"), |
| 56 | "NMTOKEN": minidom.TypeInfo(None, "nmtoken"), |
| 57 | "NMTOKENS": minidom.TypeInfo(None, "nmtokens"), |
| 58 | } |
| 59 | |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 60 | class ElementInfo(object): |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 61 | __slots__ = '_attr_info', '_model', 'tagName' |
| 62 | |
| 63 | def __init__(self, tagName, model=None): |
| 64 | self.tagName = tagName |
| 65 | self._attr_info = [] |
| 66 | self._model = model |
| 67 | |
| 68 | def __getstate__(self): |
| 69 | return self._attr_info, self._model, self.tagName |
| 70 | |
| 71 | def __setstate__(self, state): |
| 72 | self._attr_info, self._model, self.tagName = state |
| 73 | |
| 74 | def getAttributeType(self, aname): |
| 75 | for info in self._attr_info: |
| 76 | if info[1] == aname: |
| 77 | t = info[-2] |
| 78 | if t[0] == "(": |
| 79 | return _typeinfo_map["ENUM"] |
| 80 | else: |
| 81 | return _typeinfo_map[info[-2]] |
| 82 | return minidom._no_type |
| 83 | |
| 84 | def getAttributeTypeNS(self, namespaceURI, localName): |
| 85 | return minidom._no_type |
| 86 | |
| 87 | def isElementContent(self): |
| 88 | if self._model: |
| 89 | type = self._model[0] |
| 90 | return type not in (expat.model.XML_CTYPE_ANY, |
| 91 | expat.model.XML_CTYPE_MIXED) |
| 92 | else: |
| 93 | return False |
| 94 | |
| 95 | def isEmpty(self): |
| 96 | if self._model: |
| 97 | return self._model[0] == expat.model.XML_CTYPE_EMPTY |
| 98 | else: |
| 99 | return False |
| 100 | |
| 101 | def isId(self, aname): |
| 102 | for info in self._attr_info: |
| 103 | if info[1] == aname: |
| 104 | return info[-2] == "ID" |
| 105 | return False |
| 106 | |
| 107 | def isIdNS(self, euri, ename, auri, aname): |
| 108 | # not sure this is meaningful |
| 109 | return self.isId((auri, aname)) |
| 110 | |
| 111 | def _intern(builder, s): |
| 112 | return builder._intern_setdefault(s, s) |
| 113 | |
| 114 | def _parse_ns_name(builder, name): |
| 115 | assert ' ' in name |
| 116 | parts = name.split(' ') |
| 117 | intern = builder._intern_setdefault |
| 118 | if len(parts) == 3: |
| 119 | uri, localname, prefix = parts |
| 120 | prefix = intern(prefix, prefix) |
| 121 | qname = "%s:%s" % (prefix, localname) |
| 122 | qname = intern(qname, qname) |
| 123 | localname = intern(localname, localname) |
| 124 | else: |
| 125 | uri, localname = parts |
| 126 | prefix = EMPTY_PREFIX |
| 127 | qname = localname = intern(localname, localname) |
| 128 | return intern(uri, uri), localname, prefix, qname |
| 129 | |
| 130 | |
| 131 | class ExpatBuilder: |
| 132 | """Document builder that uses Expat to build a ParsedXML.DOM document |
| 133 | instance.""" |
| 134 | |
| 135 | def __init__(self, options=None): |
| 136 | if options is None: |
| 137 | options = xmlbuilder.Options() |
| 138 | self._options = options |
| 139 | if self._options.filter is not None: |
| 140 | self._filter = FilterVisibilityController(self._options.filter) |
| 141 | else: |
| 142 | self._filter = None |
| 143 | # This *really* doesn't do anything in this case, so |
| 144 | # override it with something fast & minimal. |
| 145 | self._finish_start_element = id |
| 146 | self._parser = None |
| 147 | self.reset() |
| 148 | |
| 149 | def createParser(self): |
| 150 | """Create a new parser object.""" |
| 151 | return expat.ParserCreate() |
| 152 | |
| 153 | def getParser(self): |
| 154 | """Return the parser object, creating a new one if needed.""" |
| 155 | if not self._parser: |
| 156 | self._parser = self.createParser() |
| 157 | self._intern_setdefault = self._parser.intern.setdefault |
| 158 | self._parser.buffer_text = True |
| 159 | self._parser.ordered_attributes = True |
| 160 | self._parser.specified_attributes = True |
| 161 | self.install(self._parser) |
| 162 | return self._parser |
| 163 | |
| 164 | def reset(self): |
| 165 | """Free all data structures used during DOM construction.""" |
| 166 | self.document = theDOMImplementation.createDocument( |
| 167 | EMPTY_NAMESPACE, None, None) |
| 168 | self.curNode = self.document |
| 169 | self._elem_info = self.document._elem_info |
| 170 | self._cdata = False |
| 171 | |
| 172 | def install(self, parser): |
| 173 | """Install the callbacks needed to build the DOM into the parser.""" |
| 174 | # This creates circular references! |
| 175 | parser.StartDoctypeDeclHandler = self.start_doctype_decl_handler |
| 176 | parser.StartElementHandler = self.first_element_handler |
| 177 | parser.EndElementHandler = self.end_element_handler |
| 178 | parser.ProcessingInstructionHandler = self.pi_handler |
| 179 | if self._options.entities: |
| 180 | parser.EntityDeclHandler = self.entity_decl_handler |
| 181 | parser.NotationDeclHandler = self.notation_decl_handler |
| 182 | if self._options.comments: |
| 183 | parser.CommentHandler = self.comment_handler |
| 184 | if self._options.cdata_sections: |
| 185 | parser.StartCdataSectionHandler = self.start_cdata_section_handler |
| 186 | parser.EndCdataSectionHandler = self.end_cdata_section_handler |
| 187 | parser.CharacterDataHandler = self.character_data_handler_cdata |
| 188 | else: |
| 189 | parser.CharacterDataHandler = self.character_data_handler |
| 190 | parser.ExternalEntityRefHandler = self.external_entity_ref_handler |
| 191 | parser.XmlDeclHandler = self.xml_decl_handler |
| 192 | parser.ElementDeclHandler = self.element_decl_handler |
| 193 | parser.AttlistDeclHandler = self.attlist_decl_handler |
| 194 | |
| 195 | def parseFile(self, file): |
| 196 | """Parse a document from a file object, returning the document |
| 197 | node.""" |
| 198 | parser = self.getParser() |
| 199 | first_buffer = True |
| 200 | try: |
| 201 | while 1: |
| 202 | buffer = file.read(16*1024) |
| 203 | if not buffer: |
| 204 | break |
| 205 | parser.Parse(buffer, 0) |
| 206 | if first_buffer and self.document.documentElement: |
| 207 | self._setup_subset(buffer) |
| 208 | first_buffer = False |
| 209 | parser.Parse("", True) |
| 210 | except ParseEscape: |
| 211 | pass |
| 212 | doc = self.document |
| 213 | self.reset() |
| 214 | self._parser = None |
| 215 | return doc |
| 216 | |
| 217 | def parseString(self, string): |
| 218 | """Parse a document from a string, returning the document node.""" |
| 219 | parser = self.getParser() |
| 220 | try: |
| 221 | parser.Parse(string, True) |
| 222 | self._setup_subset(string) |
| 223 | except ParseEscape: |
| 224 | pass |
| 225 | doc = self.document |
| 226 | self.reset() |
| 227 | self._parser = None |
| 228 | return doc |
| 229 | |
| 230 | def _setup_subset(self, buffer): |
| 231 | """Load the internal subset if there might be one.""" |
| 232 | if self.document.doctype: |
| 233 | extractor = InternalSubsetExtractor() |
| 234 | extractor.parseString(buffer) |
| 235 | subset = extractor.getSubset() |
| 236 | self.document.doctype.internalSubset = subset |
| 237 | |
| 238 | def start_doctype_decl_handler(self, doctypeName, systemId, publicId, |
| 239 | has_internal_subset): |
| 240 | doctype = self.document.implementation.createDocumentType( |
| 241 | doctypeName, publicId, systemId) |
| 242 | doctype.ownerDocument = self.document |
Georg Brandl | 297d972 | 2010-07-10 11:40:13 +0000 | [diff] [blame] | 243 | _append_child(self.document, doctype) |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 244 | self.document.doctype = doctype |
| 245 | if self._filter and self._filter.acceptNode(doctype) == FILTER_REJECT: |
| 246 | self.document.doctype = None |
| 247 | del self.document.childNodes[-1] |
| 248 | doctype = None |
| 249 | self._parser.EntityDeclHandler = None |
| 250 | self._parser.NotationDeclHandler = None |
| 251 | if has_internal_subset: |
| 252 | if doctype is not None: |
| 253 | doctype.entities._seq = [] |
| 254 | doctype.notations._seq = [] |
| 255 | self._parser.CommentHandler = None |
| 256 | self._parser.ProcessingInstructionHandler = None |
| 257 | self._parser.EndDoctypeDeclHandler = self.end_doctype_decl_handler |
| 258 | |
| 259 | def end_doctype_decl_handler(self): |
| 260 | if self._options.comments: |
| 261 | self._parser.CommentHandler = self.comment_handler |
| 262 | self._parser.ProcessingInstructionHandler = self.pi_handler |
| 263 | if not (self._elem_info or self._filter): |
| 264 | self._finish_end_element = id |
| 265 | |
| 266 | def pi_handler(self, target, data): |
| 267 | node = self.document.createProcessingInstruction(target, data) |
| 268 | _append_child(self.curNode, node) |
| 269 | if self._filter and self._filter.acceptNode(node) == FILTER_REJECT: |
Neal Norwitz | bc05fc5 | 2003-06-29 04:50:34 +0000 | [diff] [blame] | 270 | self.curNode.removeChild(node) |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 271 | |
| 272 | def character_data_handler_cdata(self, data): |
| 273 | childNodes = self.curNode.childNodes |
| 274 | if self._cdata: |
| 275 | if ( self._cdata_continue |
| 276 | and childNodes[-1].nodeType == CDATA_SECTION_NODE): |
| 277 | childNodes[-1].appendData(data) |
| 278 | return |
| 279 | node = self.document.createCDATASection(data) |
| 280 | self._cdata_continue = True |
| 281 | elif childNodes and childNodes[-1].nodeType == TEXT_NODE: |
| 282 | node = childNodes[-1] |
| 283 | value = node.data + data |
Martin v. Löwis | 14aa280 | 2012-02-19 20:25:12 +0100 | [diff] [blame] | 284 | node.data = value |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 285 | return |
| 286 | else: |
| 287 | node = minidom.Text() |
Martin v. Löwis | 14aa280 | 2012-02-19 20:25:12 +0100 | [diff] [blame] | 288 | node.data = data |
| 289 | node.ownerDocument = self.document |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 290 | _append_child(self.curNode, node) |
| 291 | |
| 292 | def character_data_handler(self, data): |
| 293 | childNodes = self.curNode.childNodes |
| 294 | if childNodes and childNodes[-1].nodeType == TEXT_NODE: |
| 295 | node = childNodes[-1] |
Martin v. Löwis | 14aa280 | 2012-02-19 20:25:12 +0100 | [diff] [blame] | 296 | node.data = node.data + data |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 297 | return |
| 298 | node = minidom.Text() |
Martin v. Löwis | 14aa280 | 2012-02-19 20:25:12 +0100 | [diff] [blame] | 299 | node.data = node.data + data |
| 300 | node.ownerDocument = self.document |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 301 | _append_child(self.curNode, node) |
| 302 | |
| 303 | def entity_decl_handler(self, entityName, is_parameter_entity, value, |
| 304 | base, systemId, publicId, notationName): |
| 305 | if is_parameter_entity: |
| 306 | # we don't care about parameter entities for the DOM |
| 307 | return |
| 308 | if not self._options.entities: |
| 309 | return |
| 310 | node = self.document._create_entity(entityName, publicId, |
| 311 | systemId, notationName) |
| 312 | if value is not None: |
| 313 | # internal entity |
| 314 | # node *should* be readonly, but we'll cheat |
| 315 | child = self.document.createTextNode(value) |
| 316 | node.childNodes.append(child) |
| 317 | self.document.doctype.entities._seq.append(node) |
| 318 | if self._filter and self._filter.acceptNode(node) == FILTER_REJECT: |
| 319 | del self.document.doctype.entities._seq[-1] |
| 320 | |
| 321 | def notation_decl_handler(self, notationName, base, systemId, publicId): |
| 322 | node = self.document._create_notation(notationName, publicId, systemId) |
| 323 | self.document.doctype.notations._seq.append(node) |
| 324 | if self._filter and self._filter.acceptNode(node) == FILTER_ACCEPT: |
| 325 | del self.document.doctype.notations._seq[-1] |
| 326 | |
| 327 | def comment_handler(self, data): |
| 328 | node = self.document.createComment(data) |
| 329 | _append_child(self.curNode, node) |
| 330 | if self._filter and self._filter.acceptNode(node) == FILTER_REJECT: |
Martin v. Löwis | 041411a | 2003-01-26 09:01:30 +0000 | [diff] [blame] | 331 | self.curNode.removeChild(node) |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 332 | |
| 333 | def start_cdata_section_handler(self): |
| 334 | self._cdata = True |
| 335 | self._cdata_continue = False |
| 336 | |
| 337 | def end_cdata_section_handler(self): |
| 338 | self._cdata = False |
| 339 | self._cdata_continue = False |
| 340 | |
| 341 | def external_entity_ref_handler(self, context, base, systemId, publicId): |
| 342 | return 1 |
| 343 | |
| 344 | def first_element_handler(self, name, attributes): |
| 345 | if self._filter is None and not self._elem_info: |
| 346 | self._finish_end_element = id |
| 347 | self.getParser().StartElementHandler = self.start_element_handler |
| 348 | self.start_element_handler(name, attributes) |
| 349 | |
| 350 | def start_element_handler(self, name, attributes): |
| 351 | node = self.document.createElement(name) |
| 352 | _append_child(self.curNode, node) |
| 353 | self.curNode = node |
| 354 | |
| 355 | if attributes: |
| 356 | for i in range(0, len(attributes), 2): |
| 357 | a = minidom.Attr(attributes[i], EMPTY_NAMESPACE, |
| 358 | None, EMPTY_PREFIX) |
| 359 | value = attributes[i+1] |
Martin v. Löwis | 14aa280 | 2012-02-19 20:25:12 +0100 | [diff] [blame] | 360 | a.value = value |
| 361 | a.ownerDocument = self.document |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 362 | _set_attribute_node(node, a) |
| 363 | |
| 364 | if node is not self.document.documentElement: |
| 365 | self._finish_start_element(node) |
| 366 | |
| 367 | def _finish_start_element(self, node): |
| 368 | if self._filter: |
| 369 | # To be general, we'd have to call isSameNode(), but this |
| 370 | # is sufficient for minidom: |
| 371 | if node is self.document.documentElement: |
| 372 | return |
| 373 | filt = self._filter.startContainer(node) |
| 374 | if filt == FILTER_REJECT: |
| 375 | # ignore this node & all descendents |
| 376 | Rejecter(self) |
| 377 | elif filt == FILTER_SKIP: |
| 378 | # ignore this node, but make it's children become |
| 379 | # children of the parent node |
| 380 | Skipper(self) |
| 381 | else: |
| 382 | return |
| 383 | self.curNode = node.parentNode |
| 384 | node.parentNode.removeChild(node) |
| 385 | node.unlink() |
| 386 | |
| 387 | # If this ever changes, Namespaces.end_element_handler() needs to |
| 388 | # be changed to match. |
| 389 | # |
| 390 | def end_element_handler(self, name): |
| 391 | curNode = self.curNode |
| 392 | self.curNode = curNode.parentNode |
| 393 | self._finish_end_element(curNode) |
| 394 | |
| 395 | def _finish_end_element(self, curNode): |
| 396 | info = self._elem_info.get(curNode.tagName) |
| 397 | if info: |
| 398 | self._handle_white_text_nodes(curNode, info) |
| 399 | if self._filter: |
| 400 | if curNode is self.document.documentElement: |
| 401 | return |
| 402 | if self._filter.acceptNode(curNode) == FILTER_REJECT: |
| 403 | self.curNode.removeChild(curNode) |
| 404 | curNode.unlink() |
| 405 | |
| 406 | def _handle_white_text_nodes(self, node, info): |
| 407 | if (self._options.whitespace_in_element_content |
| 408 | or not info.isElementContent()): |
| 409 | return |
| 410 | |
| 411 | # We have element type information and should remove ignorable |
| 412 | # whitespace; identify for text nodes which contain only |
| 413 | # whitespace. |
| 414 | L = [] |
| 415 | for child in node.childNodes: |
| 416 | if child.nodeType == TEXT_NODE and not child.data.strip(): |
| 417 | L.append(child) |
| 418 | |
| 419 | # Remove ignorable whitespace from the tree. |
| 420 | for child in L: |
| 421 | node.removeChild(child) |
| 422 | |
| 423 | def element_decl_handler(self, name, model): |
| 424 | info = self._elem_info.get(name) |
| 425 | if info is None: |
| 426 | self._elem_info[name] = ElementInfo(name, model) |
| 427 | else: |
| 428 | assert info._model is None |
| 429 | info._model = model |
| 430 | |
| 431 | def attlist_decl_handler(self, elem, name, type, default, required): |
| 432 | info = self._elem_info.get(elem) |
| 433 | if info is None: |
| 434 | info = ElementInfo(elem) |
| 435 | self._elem_info[elem] = info |
| 436 | info._attr_info.append( |
| 437 | [None, name, None, None, default, 0, type, required]) |
| 438 | |
| 439 | def xml_decl_handler(self, version, encoding, standalone): |
| 440 | self.document.version = version |
| 441 | self.document.encoding = encoding |
| 442 | # This is still a little ugly, thanks to the pyexpat API. ;-( |
| 443 | if standalone >= 0: |
| 444 | if standalone: |
| 445 | self.document.standalone = True |
| 446 | else: |
| 447 | self.document.standalone = False |
| 448 | |
| 449 | |
| 450 | # Don't include FILTER_INTERRUPT, since that's checked separately |
| 451 | # where allowed. |
| 452 | _ALLOWED_FILTER_RETURNS = (FILTER_ACCEPT, FILTER_REJECT, FILTER_SKIP) |
| 453 | |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 454 | class FilterVisibilityController(object): |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 455 | """Wrapper around a DOMBuilderFilter which implements the checks |
| 456 | to make the whatToShow filter attribute work.""" |
| 457 | |
| 458 | __slots__ = 'filter', |
| 459 | |
| 460 | def __init__(self, filter): |
| 461 | self.filter = filter |
| 462 | |
| 463 | def startContainer(self, node): |
| 464 | mask = self._nodetype_mask[node.nodeType] |
| 465 | if self.filter.whatToShow & mask: |
| 466 | val = self.filter.startContainer(node) |
| 467 | if val == FILTER_INTERRUPT: |
| 468 | raise ParseEscape |
| 469 | if val not in _ALLOWED_FILTER_RETURNS: |
Collin Winter | 70e7980 | 2007-08-24 18:57:22 +0000 | [diff] [blame] | 470 | raise ValueError( |
| 471 | "startContainer() returned illegal value: " + repr(val)) |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 472 | return val |
| 473 | else: |
| 474 | return FILTER_ACCEPT |
| 475 | |
| 476 | def acceptNode(self, node): |
| 477 | mask = self._nodetype_mask[node.nodeType] |
| 478 | if self.filter.whatToShow & mask: |
| 479 | val = self.filter.acceptNode(node) |
| 480 | if val == FILTER_INTERRUPT: |
| 481 | raise ParseEscape |
| 482 | if val == FILTER_SKIP: |
| 483 | # move all child nodes to the parent, and remove this node |
| 484 | parent = node.parentNode |
| 485 | for child in node.childNodes[:]: |
| 486 | parent.appendChild(child) |
| 487 | # node is handled by the caller |
| 488 | return FILTER_REJECT |
| 489 | if val not in _ALLOWED_FILTER_RETURNS: |
Collin Winter | 70e7980 | 2007-08-24 18:57:22 +0000 | [diff] [blame] | 490 | raise ValueError( |
| 491 | "acceptNode() returned illegal value: " + repr(val)) |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 492 | return val |
| 493 | else: |
| 494 | return FILTER_ACCEPT |
| 495 | |
| 496 | _nodetype_mask = { |
| 497 | Node.ELEMENT_NODE: NodeFilter.SHOW_ELEMENT, |
| 498 | Node.ATTRIBUTE_NODE: NodeFilter.SHOW_ATTRIBUTE, |
| 499 | Node.TEXT_NODE: NodeFilter.SHOW_TEXT, |
| 500 | Node.CDATA_SECTION_NODE: NodeFilter.SHOW_CDATA_SECTION, |
| 501 | Node.ENTITY_REFERENCE_NODE: NodeFilter.SHOW_ENTITY_REFERENCE, |
| 502 | Node.ENTITY_NODE: NodeFilter.SHOW_ENTITY, |
| 503 | Node.PROCESSING_INSTRUCTION_NODE: NodeFilter.SHOW_PROCESSING_INSTRUCTION, |
| 504 | Node.COMMENT_NODE: NodeFilter.SHOW_COMMENT, |
| 505 | Node.DOCUMENT_NODE: NodeFilter.SHOW_DOCUMENT, |
| 506 | Node.DOCUMENT_TYPE_NODE: NodeFilter.SHOW_DOCUMENT_TYPE, |
| 507 | Node.DOCUMENT_FRAGMENT_NODE: NodeFilter.SHOW_DOCUMENT_FRAGMENT, |
| 508 | Node.NOTATION_NODE: NodeFilter.SHOW_NOTATION, |
| 509 | } |
| 510 | |
| 511 | |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 512 | class FilterCrutch(object): |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 513 | __slots__ = '_builder', '_level', '_old_start', '_old_end' |
| 514 | |
| 515 | def __init__(self, builder): |
| 516 | self._level = 0 |
| 517 | self._builder = builder |
| 518 | parser = builder._parser |
| 519 | self._old_start = parser.StartElementHandler |
| 520 | self._old_end = parser.EndElementHandler |
| 521 | parser.StartElementHandler = self.start_element_handler |
| 522 | parser.EndElementHandler = self.end_element_handler |
| 523 | |
| 524 | class Rejecter(FilterCrutch): |
| 525 | __slots__ = () |
| 526 | |
| 527 | def __init__(self, builder): |
| 528 | FilterCrutch.__init__(self, builder) |
| 529 | parser = builder._parser |
| 530 | for name in ("ProcessingInstructionHandler", |
| 531 | "CommentHandler", |
| 532 | "CharacterDataHandler", |
| 533 | "StartCdataSectionHandler", |
| 534 | "EndCdataSectionHandler", |
| 535 | "ExternalEntityRefHandler", |
| 536 | ): |
| 537 | setattr(parser, name, None) |
| 538 | |
| 539 | def start_element_handler(self, *args): |
| 540 | self._level = self._level + 1 |
| 541 | |
| 542 | def end_element_handler(self, *args): |
| 543 | if self._level == 0: |
| 544 | # restore the old handlers |
| 545 | parser = self._builder._parser |
| 546 | self._builder.install(parser) |
| 547 | parser.StartElementHandler = self._old_start |
| 548 | parser.EndElementHandler = self._old_end |
| 549 | else: |
| 550 | self._level = self._level - 1 |
| 551 | |
| 552 | class Skipper(FilterCrutch): |
| 553 | __slots__ = () |
| 554 | |
| 555 | def start_element_handler(self, *args): |
| 556 | node = self._builder.curNode |
| 557 | self._old_start(*args) |
| 558 | if self._builder.curNode is not node: |
| 559 | self._level = self._level + 1 |
| 560 | |
| 561 | def end_element_handler(self, *args): |
| 562 | if self._level == 0: |
| 563 | # We're popping back out of the node we're skipping, so we |
| 564 | # shouldn't need to do anything but reset the handlers. |
| 565 | self._builder._parser.StartElementHandler = self._old_start |
| 566 | self._builder._parser.EndElementHandler = self._old_end |
| 567 | self._builder = None |
| 568 | else: |
| 569 | self._level = self._level - 1 |
| 570 | self._old_end(*args) |
| 571 | |
| 572 | |
| 573 | # framework document used by the fragment builder. |
| 574 | # Takes a string for the doctype, subset string, and namespace attrs string. |
| 575 | |
| 576 | _FRAGMENT_BUILDER_INTERNAL_SYSTEM_ID = \ |
| 577 | "http://xml.python.org/entities/fragment-builder/internal" |
| 578 | |
| 579 | _FRAGMENT_BUILDER_TEMPLATE = ( |
| 580 | '''\ |
| 581 | <!DOCTYPE wrapper |
| 582 | %%s [ |
| 583 | <!ENTITY fragment-builder-internal |
| 584 | SYSTEM "%s"> |
| 585 | %%s |
| 586 | ]> |
| 587 | <wrapper %%s |
| 588 | >&fragment-builder-internal;</wrapper>''' |
| 589 | % _FRAGMENT_BUILDER_INTERNAL_SYSTEM_ID) |
| 590 | |
| 591 | |
| 592 | class FragmentBuilder(ExpatBuilder): |
| 593 | """Builder which constructs document fragments given XML source |
| 594 | text and a context node. |
| 595 | |
| 596 | The context node is expected to provide information about the |
| 597 | namespace declarations which are in scope at the start of the |
| 598 | fragment. |
| 599 | """ |
| 600 | |
| 601 | def __init__(self, context, options=None): |
| 602 | if context.nodeType == DOCUMENT_NODE: |
| 603 | self.originalDocument = context |
| 604 | self.context = context |
| 605 | else: |
| 606 | self.originalDocument = context.ownerDocument |
| 607 | self.context = context |
| 608 | ExpatBuilder.__init__(self, options) |
| 609 | |
| 610 | def reset(self): |
| 611 | ExpatBuilder.reset(self) |
| 612 | self.fragment = None |
| 613 | |
| 614 | def parseFile(self, file): |
| 615 | """Parse a document fragment from a file object, returning the |
| 616 | fragment node.""" |
| 617 | return self.parseString(file.read()) |
| 618 | |
| 619 | def parseString(self, string): |
| 620 | """Parse a document fragment from a string, returning the |
| 621 | fragment node.""" |
| 622 | self._source = string |
| 623 | parser = self.getParser() |
| 624 | doctype = self.originalDocument.doctype |
| 625 | ident = "" |
| 626 | if doctype: |
| 627 | subset = doctype.internalSubset or self._getDeclarations() |
| 628 | if doctype.publicId: |
| 629 | ident = ('PUBLIC "%s" "%s"' |
| 630 | % (doctype.publicId, doctype.systemId)) |
| 631 | elif doctype.systemId: |
| 632 | ident = 'SYSTEM "%s"' % doctype.systemId |
| 633 | else: |
| 634 | subset = "" |
| 635 | nsattrs = self._getNSattrs() # get ns decls from node's ancestors |
| 636 | document = _FRAGMENT_BUILDER_TEMPLATE % (ident, subset, nsattrs) |
| 637 | try: |
| 638 | parser.Parse(document, 1) |
| 639 | except: |
| 640 | self.reset() |
| 641 | raise |
| 642 | fragment = self.fragment |
| 643 | self.reset() |
| 644 | ## self._parser = None |
| 645 | return fragment |
| 646 | |
| 647 | def _getDeclarations(self): |
| 648 | """Re-create the internal subset from the DocumentType node. |
| 649 | |
| 650 | This is only needed if we don't already have the |
| 651 | internalSubset as a string. |
| 652 | """ |
| 653 | doctype = self.context.ownerDocument.doctype |
| 654 | s = "" |
| 655 | if doctype: |
| 656 | for i in range(doctype.notations.length): |
| 657 | notation = doctype.notations.item(i) |
| 658 | if s: |
| 659 | s = s + "\n " |
| 660 | s = "%s<!NOTATION %s" % (s, notation.nodeName) |
| 661 | if notation.publicId: |
| 662 | s = '%s PUBLIC "%s"\n "%s">' \ |
| 663 | % (s, notation.publicId, notation.systemId) |
| 664 | else: |
| 665 | s = '%s SYSTEM "%s">' % (s, notation.systemId) |
| 666 | for i in range(doctype.entities.length): |
| 667 | entity = doctype.entities.item(i) |
| 668 | if s: |
| 669 | s = s + "\n " |
| 670 | s = "%s<!ENTITY %s" % (s, entity.nodeName) |
| 671 | if entity.publicId: |
| 672 | s = '%s PUBLIC "%s"\n "%s"' \ |
| 673 | % (s, entity.publicId, entity.systemId) |
| 674 | elif entity.systemId: |
| 675 | s = '%s SYSTEM "%s"' % (s, entity.systemId) |
| 676 | else: |
| 677 | s = '%s "%s"' % (s, entity.firstChild.data) |
| 678 | if entity.notationName: |
| 679 | s = "%s NOTATION %s" % (s, entity.notationName) |
| 680 | s = s + ">" |
| 681 | return s |
| 682 | |
| 683 | def _getNSattrs(self): |
| 684 | return "" |
| 685 | |
| 686 | def external_entity_ref_handler(self, context, base, systemId, publicId): |
| 687 | if systemId == _FRAGMENT_BUILDER_INTERNAL_SYSTEM_ID: |
| 688 | # this entref is the one that we made to put the subtree |
| 689 | # in; all of our given input is parsed in here. |
| 690 | old_document = self.document |
| 691 | old_cur_node = self.curNode |
| 692 | parser = self._parser.ExternalEntityParserCreate(context) |
| 693 | # put the real document back, parse into the fragment to return |
| 694 | self.document = self.originalDocument |
| 695 | self.fragment = self.document.createDocumentFragment() |
| 696 | self.curNode = self.fragment |
| 697 | try: |
| 698 | parser.Parse(self._source, 1) |
| 699 | finally: |
| 700 | self.curNode = old_cur_node |
| 701 | self.document = old_document |
| 702 | self._source = None |
| 703 | return -1 |
| 704 | else: |
| 705 | return ExpatBuilder.external_entity_ref_handler( |
| 706 | self, context, base, systemId, publicId) |
| 707 | |
| 708 | |
| 709 | class Namespaces: |
| 710 | """Mix-in class for builders; adds support for namespaces.""" |
| 711 | |
| 712 | def _initNamespaces(self): |
| 713 | # list of (prefix, uri) ns declarations. Namespace attrs are |
| 714 | # constructed from this and added to the element's attrs. |
| 715 | self._ns_ordered_prefixes = [] |
| 716 | |
| 717 | def createParser(self): |
| 718 | """Create a new namespace-handling parser.""" |
| 719 | parser = expat.ParserCreate(namespace_separator=" ") |
| 720 | parser.namespace_prefixes = True |
| 721 | return parser |
| 722 | |
| 723 | def install(self, parser): |
| 724 | """Insert the namespace-handlers onto the parser.""" |
| 725 | ExpatBuilder.install(self, parser) |
| 726 | if self._options.namespace_declarations: |
| 727 | parser.StartNamespaceDeclHandler = ( |
| 728 | self.start_namespace_decl_handler) |
| 729 | |
| 730 | def start_namespace_decl_handler(self, prefix, uri): |
| 731 | """Push this namespace declaration on our storage.""" |
| 732 | self._ns_ordered_prefixes.append((prefix, uri)) |
| 733 | |
| 734 | def start_element_handler(self, name, attributes): |
| 735 | if ' ' in name: |
| 736 | uri, localname, prefix, qname = _parse_ns_name(self, name) |
| 737 | else: |
| 738 | uri = EMPTY_NAMESPACE |
| 739 | qname = name |
| 740 | localname = None |
| 741 | prefix = EMPTY_PREFIX |
| 742 | node = minidom.Element(qname, uri, prefix, localname) |
| 743 | node.ownerDocument = self.document |
| 744 | _append_child(self.curNode, node) |
| 745 | self.curNode = node |
| 746 | |
| 747 | if self._ns_ordered_prefixes: |
| 748 | for prefix, uri in self._ns_ordered_prefixes: |
| 749 | if prefix: |
| 750 | a = minidom.Attr(_intern(self, 'xmlns:' + prefix), |
| 751 | XMLNS_NAMESPACE, prefix, "xmlns") |
| 752 | else: |
| 753 | a = minidom.Attr("xmlns", XMLNS_NAMESPACE, |
| 754 | "xmlns", EMPTY_PREFIX) |
Martin v. Löwis | 14aa280 | 2012-02-19 20:25:12 +0100 | [diff] [blame] | 755 | a.value = uri |
Florent Xicluna | 6c75301 | 2012-03-05 12:35:15 +0100 | [diff] [blame] | 756 | a.ownerDocument = self.document |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 757 | _set_attribute_node(node, a) |
| 758 | del self._ns_ordered_prefixes[:] |
| 759 | |
| 760 | if attributes: |
Martin v. Löwis | 7b77188 | 2012-02-19 20:55:05 +0100 | [diff] [blame] | 761 | node._ensure_attributes() |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 762 | _attrs = node._attrs |
| 763 | _attrsNS = node._attrsNS |
| 764 | for i in range(0, len(attributes), 2): |
| 765 | aname = attributes[i] |
| 766 | value = attributes[i+1] |
| 767 | if ' ' in aname: |
| 768 | uri, localname, prefix, qname = _parse_ns_name(self, aname) |
| 769 | a = minidom.Attr(qname, uri, localname, prefix) |
| 770 | _attrs[qname] = a |
| 771 | _attrsNS[(uri, localname)] = a |
| 772 | else: |
| 773 | a = minidom.Attr(aname, EMPTY_NAMESPACE, |
| 774 | aname, EMPTY_PREFIX) |
| 775 | _attrs[aname] = a |
| 776 | _attrsNS[(EMPTY_NAMESPACE, aname)] = a |
Martin v. Löwis | 14aa280 | 2012-02-19 20:25:12 +0100 | [diff] [blame] | 777 | a.ownerDocument = self.document |
| 778 | a.value = value |
| 779 | a.ownerElement = node |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 780 | |
| 781 | if __debug__: |
| 782 | # This only adds some asserts to the original |
| 783 | # end_element_handler(), so we only define this when -O is not |
| 784 | # used. If changing one, be sure to check the other to see if |
| 785 | # it needs to be changed as well. |
| 786 | # |
| 787 | def end_element_handler(self, name): |
| 788 | curNode = self.curNode |
| 789 | if ' ' in name: |
| 790 | uri, localname, prefix, qname = _parse_ns_name(self, name) |
| 791 | assert (curNode.namespaceURI == uri |
| 792 | and curNode.localName == localname |
| 793 | and curNode.prefix == prefix), \ |
| 794 | "element stack messed up! (namespace)" |
| 795 | else: |
| 796 | assert curNode.nodeName == name, \ |
| 797 | "element stack messed up - bad nodeName" |
| 798 | assert curNode.namespaceURI == EMPTY_NAMESPACE, \ |
| 799 | "element stack messed up - bad namespaceURI" |
| 800 | self.curNode = curNode.parentNode |
| 801 | self._finish_end_element(curNode) |
| 802 | |
| 803 | |
| 804 | class ExpatBuilderNS(Namespaces, ExpatBuilder): |
| 805 | """Document builder that supports namespaces.""" |
| 806 | |
| 807 | def reset(self): |
| 808 | ExpatBuilder.reset(self) |
| 809 | self._initNamespaces() |
| 810 | |
| 811 | |
| 812 | class FragmentBuilderNS(Namespaces, FragmentBuilder): |
| 813 | """Fragment builder that supports namespaces.""" |
| 814 | |
| 815 | def reset(self): |
| 816 | FragmentBuilder.reset(self) |
| 817 | self._initNamespaces() |
| 818 | |
| 819 | def _getNSattrs(self): |
| 820 | """Return string of namespace attributes from this element and |
| 821 | ancestors.""" |
| 822 | # XXX This needs to be re-written to walk the ancestors of the |
| 823 | # context to build up the namespace information from |
| 824 | # declarations, elements, and attributes found in context. |
| 825 | # Otherwise we have to store a bunch more data on the DOM |
| 826 | # (though that *might* be more reliable -- not clear). |
| 827 | attrs = "" |
| 828 | context = self.context |
| 829 | L = [] |
| 830 | while context: |
| 831 | if hasattr(context, '_ns_prefix_uri'): |
| 832 | for prefix, uri in context._ns_prefix_uri.items(): |
| 833 | # add every new NS decl from context to L and attrs string |
| 834 | if prefix in L: |
| 835 | continue |
| 836 | L.append(prefix) |
| 837 | if prefix: |
| 838 | declname = "xmlns:" + prefix |
| 839 | else: |
| 840 | declname = "xmlns" |
| 841 | if attrs: |
| 842 | attrs = "%s\n %s='%s'" % (attrs, declname, uri) |
| 843 | else: |
| 844 | attrs = " %s='%s'" % (declname, uri) |
| 845 | context = context.parentNode |
| 846 | return attrs |
| 847 | |
| 848 | |
| 849 | class ParseEscape(Exception): |
| 850 | """Exception raised to short-circuit parsing in InternalSubsetExtractor.""" |
| 851 | pass |
| 852 | |
| 853 | class InternalSubsetExtractor(ExpatBuilder): |
| 854 | """XML processor which can rip out the internal document type subset.""" |
| 855 | |
| 856 | subset = None |
| 857 | |
| 858 | def getSubset(self): |
| 859 | """Return the internal subset as a string.""" |
| 860 | return self.subset |
| 861 | |
| 862 | def parseFile(self, file): |
| 863 | try: |
| 864 | ExpatBuilder.parseFile(self, file) |
| 865 | except ParseEscape: |
| 866 | pass |
| 867 | |
| 868 | def parseString(self, string): |
| 869 | try: |
| 870 | ExpatBuilder.parseString(self, string) |
| 871 | except ParseEscape: |
| 872 | pass |
| 873 | |
| 874 | def install(self, parser): |
| 875 | parser.StartDoctypeDeclHandler = self.start_doctype_decl_handler |
| 876 | parser.StartElementHandler = self.start_element_handler |
| 877 | |
| 878 | def start_doctype_decl_handler(self, name, publicId, systemId, |
| 879 | has_internal_subset): |
| 880 | if has_internal_subset: |
| 881 | parser = self.getParser() |
| 882 | self.subset = [] |
| 883 | parser.DefaultHandler = self.subset.append |
| 884 | parser.EndDoctypeDeclHandler = self.end_doctype_decl_handler |
| 885 | else: |
| 886 | raise ParseEscape() |
| 887 | |
| 888 | def end_doctype_decl_handler(self): |
| 889 | s = ''.join(self.subset).replace('\r\n', '\n').replace('\r', '\n') |
| 890 | self.subset = s |
| 891 | raise ParseEscape() |
| 892 | |
| 893 | def start_element_handler(self, name, attrs): |
| 894 | raise ParseEscape() |
| 895 | |
| 896 | |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 897 | def parse(file, namespaces=True): |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 898 | """Parse a document, returning the resulting Document node. |
| 899 | |
| 900 | 'file' may be either a file name or an open file object. |
| 901 | """ |
| 902 | if namespaces: |
| 903 | builder = ExpatBuilderNS() |
| 904 | else: |
| 905 | builder = ExpatBuilder() |
| 906 | |
Christian Heimes | c9543e4 | 2007-11-28 08:28:28 +0000 | [diff] [blame] | 907 | if isinstance(file, str): |
Giampaolo Rodola' | 2f50aaf | 2013-02-12 02:04:27 +0100 | [diff] [blame] | 908 | with open(file, 'rb') as fp: |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 909 | result = builder.parseFile(fp) |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 910 | else: |
| 911 | result = builder.parseFile(file) |
| 912 | return result |
| 913 | |
| 914 | |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 915 | def parseString(string, namespaces=True): |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 916 | """Parse a document from a string, returning the resulting |
| 917 | Document node. |
| 918 | """ |
| 919 | if namespaces: |
| 920 | builder = ExpatBuilderNS() |
| 921 | else: |
| 922 | builder = ExpatBuilder() |
| 923 | return builder.parseString(string) |
| 924 | |
| 925 | |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 926 | def parseFragment(file, context, namespaces=True): |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 927 | """Parse a fragment of a document, given the context from which it |
| 928 | was originally extracted. context should be the parent of the |
| 929 | node(s) which are in the fragment. |
| 930 | |
| 931 | 'file' may be either a file name or an open file object. |
| 932 | """ |
| 933 | if namespaces: |
| 934 | builder = FragmentBuilderNS(context) |
| 935 | else: |
| 936 | builder = FragmentBuilder(context) |
| 937 | |
Christian Heimes | c9543e4 | 2007-11-28 08:28:28 +0000 | [diff] [blame] | 938 | if isinstance(file, str): |
Giampaolo Rodola' | 2f50aaf | 2013-02-12 02:04:27 +0100 | [diff] [blame] | 939 | with open(file, 'rb') as fp: |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 940 | result = builder.parseFile(fp) |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 941 | else: |
| 942 | result = builder.parseFile(file) |
| 943 | return result |
| 944 | |
| 945 | |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 946 | def parseFragmentString(string, context, namespaces=True): |
Martin v. Löwis | fc5fec7 | 2003-01-25 15:11:07 +0000 | [diff] [blame] | 947 | """Parse a fragment of a document from a string, given the context |
| 948 | from which it was originally extracted. context should be the |
| 949 | parent of the node(s) which are in the fragment. |
| 950 | """ |
| 951 | if namespaces: |
| 952 | builder = FragmentBuilderNS(context) |
| 953 | else: |
| 954 | builder = FragmentBuilder(context) |
| 955 | return builder.parseString(string) |
| 956 | |
| 957 | |
| 958 | def makeBuilder(options): |
| 959 | """Create a builder based on an Options object.""" |
| 960 | if options.namespaces: |
| 961 | return ExpatBuilderNS(options) |
| 962 | else: |
| 963 | return ExpatBuilder(options) |