"""Beautiful Soup Elixir and Tonic "The Screen-Scraper's Friend" http://www.crummy.com/software/BeautifulSoup/ Beautiful Soup parses a (possibly invalid) XML or HTML document into a tree representation. It provides methods and Pythonic idioms that make it easy to navigate, search, and modify the tree. A well-formed XML/HTML document yields a well-formed data structure. An ill-formed XML/HTML document yields a correspondingly ill-formed data structure. If your document is only locally well-formed, you can use this library to find and process the well-formed part of it. Beautiful Soup works with Python 2.2 and up. It has no external dependencies, but you'll have more success at converting data to UTF-8 if you also install these three packages: * chardet, for auto-detecting character encodings http://chardet.feedparser.org/ * cjkcodecs and iconv_codec, which add more encodings to the ones supported by stock Python. http://cjkpython.i18n.org/ Beautiful Soup defines classes for two main parsing strategies: * BeautifulStoneSoup, for parsing XML, SGML, or your domain-specific language that kind of looks like XML. * BeautifulSoup, for parsing run-of-the-mill HTML code, be it valid or invalid. This class has web browser-like heuristics for obtaining a sensible parse tree in the face of common HTML errors. Beautiful Soup also defines a class (UnicodeDammit) for autodetecting the encoding of an HTML or XML document, and converting it to Unicode. Much of this code is taken from Mark Pilgrim's Universal Feed Parser. For more than you ever wanted to know about Beautiful Soup, see the documentation: http://www.crummy.com/software/BeautifulSoup/documentation.html Here, have some legalese: Copyright (c) 2004-2010, Leonard Richardson All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. * Neither the name of the the Beautiful Soup Consortium and All Night Kosher Bakery nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE, DAMMIT. """ from __future__ import generators __author__ = "Leonard Richardson (leonardr@segfault.org)" __version__ = "3.2.1" __copyright__ = "Copyright (c) 2004-2012 Leonard Richardson" __license__ = "New-style BSD" from sgmllib import SGMLParser, SGMLParseError import codecs import markupbase import re import sgmllib try: from htmlentitydefs import name2codepoint except ImportError: name2codepoint = {} try: set except NameError: from sets import Set as set # These hacks make Beautiful Soup able to parse XML with namespaces sgmllib.tagfind = re.compile('[a-zA-Z][-_.:a-zA-Z0-9]*') markupbase._declname_match = re.compile(r'[a-zA-Z][-_.:a-zA-Z0-9]*\s*').match DEFAULT_OUTPUT_ENCODING = "utf-8" def _match_css_class(str): """Build a RE to match the given CSS class.""" return re.compile(r"(^|.*\s)%s($|\s)" % str) # First, the classes that represent markup elements. class PageElement(object): """Contains the navigational information for some part of the page (either a tag or a piece of text)""" def _invert(h): "Cheap function to invert a hash." i = {} for k, v in h.items(): i[v] = k return i XML_ENTITIES_TO_SPECIAL_CHARS = {"apos": "'", "quot": '"', "amp": "&", "lt": "<", "gt": ">"} XML_SPECIAL_CHARS_TO_ENTITIES = _invert(XML_ENTITIES_TO_SPECIAL_CHARS) def setup(self, parent=None, previous=None): """Sets up the initial relations between this element and other elements.""" self.parent = parent self.previous = previous self.next = None self.previousSibling = None self.nextSibling = None if self.parent and self.parent.contents: self.previousSibling = self.parent.contents[-1] self.previousSibling.nextSibling = self def replaceWith(self, replaceWith): oldParent = self.parent myIndex = self.parent.index(self) if hasattr(replaceWith, "parent") \ and replaceWith.parent is self.parent: # We're replacing this element with one of its siblings. index = replaceWith.parent.index(replaceWith) if index and index < myIndex: # Furthermore, it comes before this element. That # means that when we extract it, the index of this # element will change. myIndex = myIndex - 1 self.extract() oldParent.insert(myIndex, replaceWith) def replaceWithChildren(self): myParent = self.parent myIndex = self.parent.index(self) self.extract() reversedChildren = list(self.contents) reversedChildren.reverse() for child in reversedChildren: myParent.insert(myIndex, child) def extract(self): """Destructively rips this element out of the tree.""" if self.parent: try: del self.parent.contents[self.parent.index(self)] except ValueError: pass # Find the two elements that would be next to each other if # this element (and any children) hadn't been parsed. Connect # the two. lastChild = self._lastRecursiveChild() nextElement = lastChild.next if self.previous: self.previous.next = nextElement if nextElement: nextElement.previous = self.previous self.previous = None lastChild.next = None self.parent = None if self.previousSibling: self.previousSibling.nextSibling = self.nextSibling if self.nextSibling: self.nextSibling.previousSibling = self.previousSibling self.previousSibling = self.nextSibling = None return self def _lastRecursiveChild(self): "Finds the last element beneath this object to be parsed." lastChild = self while hasattr(lastChild, 'contents') and lastChild.contents: lastChild = lastChild.contents[-1] return lastChild def insert(self, position, newChild): if isinstance(newChild, basestring) \ and not isinstance(newChild, NavigableString): newChild = NavigableString(newChild) position = min(position, len(self.contents)) if hasattr(newChild, 'parent') and newChild.parent is not None: # We're 'inserting' an element that's already one # of this object's children. if newChild.parent is self: index = self.index(newChild) if index > position: # Furthermore we're moving it further down the # list of this object's children. That means that # when we extract this element, our target index # will jump down one. position = position - 1 newChild.extract() newChild.parent = self previousChild = None if position == 0: newChild.previousSibling = None newChild.previous = self else: previousChild = self.contents[position - 1] newChild.previousSibling = previousChild newChild.previousSibling.nextSibling = newChild newChild.previous = previousChild._lastRecursiveChild() if newChild.previous: newChild.previous.next = newChild newChildsLastElement = newChild._lastRecursiveChild() if position >= len(self.contents): newChild.nextSibling = None parent = self parentsNextSibling = None while not parentsNextSibling: parentsNextSibling = parent.nextSibling parent = parent.parent if not parent: # This is the last element in the document. break if parentsNextSibling: newChildsLastElement.next = parentsNextSibling else: newChildsLastElement.next = None else: nextChild = self.contents[position] newChild.nextSibling = nextChild if newChild.nextSibling: newChild.nextSibling.previousSibling = newChild newChildsLastElement.next = nextChild if newChildsLastElement.next: newChildsLastElement.next.previous = newChildsLastElement self.contents.insert(position, newChild) def append(self, tag): """Appends the given tag to the contents of this tag.""" self.insert(len(self.contents), tag) def findNext(self, name=None, attrs={}, text=None, **kwargs): """Returns the first item that matches the given criteria and appears after this Tag in the document.""" return self._findOne(self.findAllNext, name, attrs, text, **kwargs) def findAllNext(self, name=None, attrs={}, text=None, limit=None, **kwargs): """Returns all items that match the given criteria and appear after this Tag in the document.""" return self._findAll(name, attrs, text, limit, self.nextGenerator, **kwargs) def findNextSibling(self, name=None, attrs={}, text=None, **kwargs): """Returns the closest sibling to this Tag that matches the given criteria and appears after this Tag in the document.""" return self._findOne(self.findNextSiblings, name, attrs, text, **kwargs) def findNextSiblings(self, name=None, attrs={}, text=None, limit=None, **kwargs): """Returns the siblings of this Tag that match the given criteria and appear after this Tag in the document.""" return self._findAll(name, attrs, text, limit, self.nextSiblingGenerator, **kwargs) fetchNextSiblings = findNextSiblings # Compatibility with pre-3.x def findPrevious(self, name=None, attrs={}, text=None, **kwargs): """Returns the first item that matches the given criteria and appears before this Tag in the document.""" return self._findOne(self.findAllPrevious, name, attrs, text, **kwargs) def findAllPrevious(self, name=None, attrs={}, text=None, limit=None, **kwargs): """Returns all items that match the given criteria and appear before this Tag in the document.""" return self._findAll(name, attrs, text, limit, self.previousGenerator, **kwargs) fetchPrevious = findAllPrevious # Compatibility with pre-3.x def findPreviousSibling(self, name=None, attrs={}, text=None, **kwargs): """Returns the closest sibling to this Tag that matches the given criteria and appears before this Tag in the document.""" return self._findOne(self.findPreviousSiblings, name, attrs, text, **kwargs) def findPreviousSiblings(self, name=None, attrs={}, text=None, limit=None, **kwargs): """Returns the siblings of this Tag that match the given criteria and appear before this Tag in the document.""" return self._findAll(name, attrs, text, limit, self.previousSiblingGenerator, **kwargs) fetchPreviousSiblings = findPreviousSiblings # Compatibility with pre-3.x def findParent(self, name=None, attrs={}, **kwargs): """Returns the closest parent of this Tag that matches the given criteria.""" # NOTE: We can't use _findOne because findParents takes a different # set of arguments. r = None l = self.findParents(name, attrs, 1) if l: r = l[0] return r def findParents(self, name=None, attrs={}, limit=None, **kwargs): """Returns the parents of this Tag that match the given criteria.""" return self._findAll(name, attrs, None, limit, self.parentGenerator, **kwargs) fetchParents = findParents # Compatibility with pre-3.x # These methods do the real heavy lifting. def _findOne(self, method, name, attrs, text, **kwargs): r = None l = method(name, attrs, text, 1, **kwargs) if l: r = l[0] return r def _findAll(self, name, attrs, text, limit, generator, **kwargs): "Iterates over a generator looking for things that match." if isinstance(name, SoupStrainer): strainer = name # (Possibly) special case some findAll*(...) searches elif text is None and not limit and not attrs and not kwargs: # findAll*(True) if name is True: return [element for element in generator() if isinstance(element, Tag)] # findAll*('tag-name') elif isinstance(name, basestring): return [element for element in generator() if isinstance(element, Tag) and element.name == name] else: strainer = SoupStrainer(name, attrs, text, **kwargs) # Build a SoupStrainer else: strainer = SoupStrainer(name, attrs, text, **kwargs) results = ResultSet(strainer) g = generator() while True: try: i = g.next() except StopIteration: break if i: found = strainer.search(i) if found: results.append(found) if limit and len(results) >= limit: break return results # These Generators can be used to navigate starting from both # NavigableStrings and Tags. def nextGenerator(self): i = self while i is not None: i = i.next yield i def nextSiblingGenerator(self): i = self while i is not None: i = i.nextSibling yield i def previousGenerator(self): i = self while i is not None: i = i.previous yield i def previousSiblingGenerator(self): i = self while i is not None: i = i.previousSibling yield i def parentGenerator(self): i = self while i is not None: i = i.parent yield i # Utility methods def substituteEncoding(self, str, encoding=None): encoding = encoding or "utf-8" return str.replace("%SOUP-ENCODING%", encoding) def toEncoding(self, s, encoding=None): """Encodes an object to a string in some encoding, or to Unicode. .""" if isinstance(s, unicode): if encoding: s = s.encode(encoding) elif isinstance(s, str): if encoding: s = s.encode(encoding) else: s = unicode(s) else: if encoding: s = self.toEncoding(str(s), encoding) else: s = unicode(s) return s BARE_AMPERSAND_OR_BRACKET = re.compile("([<>]|" + "&(?!#\d+;|#x[0-9a-fA-F]+;|\w+;)" + ")") def _sub_entity(self, x): """Used with a regular expression to substitute the appropriate XML entity for an XML special character.""" return "&" + self.XML_SPECIAL_CHARS_TO_ENTITIES[x.group(0)[0]] + ";" class NavigableString(unicode, PageElement): def __new__(cls, value): """Create a new NavigableString. When unpickling a NavigableString, this method is called with the string in DEFAULT_OUTPUT_ENCODING. That encoding needs to be passed in to the superclass's __new__ or the superclass won't know how to handle non-ASCII characters. """ if isinstance(value, unicode): return unicode.__new__(cls, value) return unicode.__new__(cls, value, DEFAULT_OUTPUT_ENCODING) def __getnewargs__(self): return (NavigableString.__str__(self),) def __getattr__(self, attr): """text.string gives you text. This is for backwards compatibility for Navigable*String, but for CData* it lets you get the string without the CData wrapper.""" if attr == 'string': return self else: raise AttributeError, "'%s' object has no attribute '%s'" % (self.__class__.__name__, attr) def __unicode__(self): return str(self).decode(DEFAULT_OUTPUT_ENCODING) def __str__(self, encoding=DEFAULT_OUTPUT_ENCODING): # Substitute outgoing XML entities. data = self.BARE_AMPERSAND_OR_BRACKET.sub(self._sub_entity, self) if encoding: return data.encode(encoding) else: return data class CData(NavigableString): def __str__(self, encoding=DEFAULT_OUTPUT_ENCODING): return "" % NavigableString.__str__(self, encoding) class ProcessingInstruction(NavigableString): def __str__(self, encoding=DEFAULT_OUTPUT_ENCODING): output = self if "%SOUP-ENCODING%" in output: output = self.substituteEncoding(output, encoding) return "" % self.toEncoding(output, encoding) class Comment(NavigableString): def __str__(self, encoding=DEFAULT_OUTPUT_ENCODING): return "" % NavigableString.__str__(self, encoding) class Declaration(NavigableString): def __str__(self, encoding=DEFAULT_OUTPUT_ENCODING): return "" % NavigableString.__str__(self, encoding) class Tag(PageElement): """Represents a found HTML tag with its attributes and contents.""" def _convertEntities(self, match): """Used in a call to re.sub to replace HTML, XML, and numeric entities with the appropriate Unicode characters. If HTML entities are being converted, any unrecognized entities are escaped.""" x = match.group(1) if self.convertHTMLEntities and x in name2codepoint: return unichr(name2codepoint[x]) elif x in self.XML_ENTITIES_TO_SPECIAL_CHARS: if self.convertXMLEntities: return self.XML_ENTITIES_TO_SPECIAL_CHARS[x] else: return u'&%s;' % x elif len(x) > 0 and x[0] == '#': # Handle numeric entities if len(x) > 1 and x[1] == 'x': return unichr(int(x[2:], 16)) else: return unichr(int(x[1:])) elif self.escapeUnrecognizedEntities: return u'&%s;' % x else: return u'&%s;' % x def __init__(self, parser, name, attrs=None, parent=None, previous=None): "Basic constructor." # We don't actually store the parser object: that lets extracted # chunks be garbage-collected self.parserClass = parser.__class__ self.isSelfClosing = parser.isSelfClosingTag(name) self.name = name if attrs is None: attrs = [] elif isinstance(attrs, dict): attrs = attrs.items() self.attrs = attrs self.contents = [] self.setup(parent, previous) self.hidden = False self.containsSubstitutions = False self.convertHTMLEntities = parser.convertHTMLEntities self.convertXMLEntities = parser.convertXMLEntities self.escapeUnrecognizedEntities = parser.escapeUnrecognizedEntities # Convert any HTML, XML, or numeric entities in the attribute values. convert = lambda (k, val): (k, re.sub("&(#\d+|#x[0-9a-fA-F]+|\w+);", self._convertEntities, val)) self.attrs = map(convert, self.attrs) def getString(self): if (len(self.contents) == 1 and isinstance(self.contents[0], NavigableString)): return self.contents[0] def setString(self, string): """Replace the contents of the tag with a string""" self.clear() self.append(string) string = property(getString, setString) def getText(self, separator=u""): if not len(self.contents): return u"" stopNode = self._lastRecursiveChild().next strings = [] current = self.contents[0] while current is not stopNode: if isinstance(current, NavigableString): strings.append(current.strip()) current = current.next return separator.join(strings) text = property(getText) def get(self, key, default=None): """Returns the value of the 'key' attribute for the tag, or the value given for 'default' if it doesn't have that attribute.""" return self._getAttrMap().get(key, default) def clear(self): """Extract all children.""" for child in self.contents[:]: child.extract() def index(self, element): for i, child in enumerate(self.contents): if child is element: return i raise ValueError("Tag.index: element not in tag") def has_key(self, key): return self._getAttrMap().has_key(key) def __getitem__(self, key): """tag[key] returns the value of the 'key' attribute for the tag, and throws an exception if it's not there.""" return self._getAttrMap()[key] def __iter__(self): "Iterating over a tag iterates over its contents." return iter(self.contents) def __len__(self): "The length of a tag is the length of its list of contents." return len(self.contents) def __contains__(self, x): return x in self.contents def __nonzero__(self): "A tag is non-None even if it has no contents." return True def __setitem__(self, key, value): """Setting tag[key] sets the value of the 'key' attribute for the tag.""" self._getAttrMap() self.attrMap[key] = value found = False for i in range(0, len(self.attrs)): if self.attrs[i][0] == key: self.attrs[i] = (key, value) found = True if not found: self.attrs.append((key, value)) self._getAttrMap()[key] = value def __delitem__(self, key): "Deleting tag[key] deletes all 'key' attributes for the tag." for item in self.attrs: if item[0] == key: self.attrs.remove(item) # We don't break because bad HTML can define the same # attribute multiple times. self._getAttrMap() if self.attrMap.has_key(key): del self.attrMap[key] def __call__(self, *args, **kwargs): """Calling a tag like a function is the same as calling its findAll() method. Eg. tag('a') returns a list of all the A tags found within this tag.""" return apply(self.findAll, args, kwargs) def __getattr__(self, tag): # print "Getattr %s.%s" % (self.__class__, tag) if len(tag) > 3 and tag.rfind('Tag') == len(tag) - 3: return self.find(tag[:-3]) elif tag.find('__') != 0: return self.find(tag) raise AttributeError, "'%s' object has no attribute '%s'" % (self.__class__, tag) def __eq__(self, other): """Returns true iff this tag has the same name, the same attributes, and the same contents (recursively) as the given tag. NOTE: right now this will return false if two tags have the same attributes in a different order. Should this be fixed?""" if other is self: return True if not hasattr(other, 'name') or not hasattr(other, 'attrs') or not hasattr(other, 'contents') or self.name != other.name or self.attrs != other.attrs or len( self) != len(other): return False for i in range(0, len(self.contents)): if self.contents[i] != other.contents[i]: return False return True def __ne__(self, other): """Returns true iff this tag is not identical to the other tag, as defined in __eq__.""" return not self == other def __repr__(self, encoding=DEFAULT_OUTPUT_ENCODING): """Renders this tag as a string.""" return self.__str__(encoding) def __unicode__(self): return self.__str__(None) def __str__(self, encoding=DEFAULT_OUTPUT_ENCODING, prettyPrint=False, indentLevel=0): """Returns a string or Unicode representation of this tag and its contents. To get Unicode, pass None for encoding. NOTE: since Python's HTML parser consumes whitespace, this method is not certain to reproduce the whitespace present in the original string.""" encodedName = self.toEncoding(self.name, encoding) attrs = [] if self.attrs: for key, val in self.attrs: fmt = '%s="%s"' if isinstance(val, basestring): if self.containsSubstitutions and '%SOUP-ENCODING%' in val: val = self.substituteEncoding(val, encoding) # The attribute value either: # # * Contains no embedded double quotes or single quotes. # No problem: we enclose it in double quotes. # * Contains embedded single quotes. No problem: # double quotes work here too. # * Contains embedded double quotes. No problem: # we enclose it in single quotes. # * Embeds both single _and_ double quotes. This # can't happen naturally, but it can happen if # you modify an attribute value after parsing # the document. Now we have a bit of a # problem. We solve it by enclosing the # attribute in single quotes, and escaping any # embedded single quotes to XML entities. if '"' in val: fmt = "%s='%s'" if "'" in val: # replace with apos when # appropriate. val = val.replace("'", "&squot;") # Now we're okay w/r/t quotes. But the attribute # value might also contain angle brackets, or # ampersands that aren't part of entities. We need # to escape those to XML entities too. val = self.BARE_AMPERSAND_OR_BRACKET.sub(self._sub_entity, val) attrs.append(fmt % (self.toEncoding(key, encoding), self.toEncoding(val, encoding))) close = '' closeTag = '' if self.isSelfClosing: close = ' /' else: closeTag = '' % encodedName indentTag, indentContents = 0, 0 if prettyPrint: indentTag = indentLevel space = (' ' * (indentTag - 1)) indentContents = indentTag + 1 contents = self.renderContents(encoding, prettyPrint, indentContents) if self.hidden: s = contents else: s = [] attributeString = '' if attrs: attributeString = ' ' + ' '.join(attrs) if prettyPrint: s.append(space) s.append('<%s%s%s>' % (encodedName, attributeString, close)) if prettyPrint: s.append("\n") s.append(contents) if prettyPrint and contents and contents[-1] != "\n": s.append("\n") if prettyPrint and closeTag: s.append(space) s.append(closeTag) if prettyPrint and closeTag and self.nextSibling: s.append("\n") s = ''.join(s) return s def decompose(self): """Recursively destroys the contents of this tree.""" self.extract() if len(self.contents) == 0: return current = self.contents[0] while current is not None: next = current.next if isinstance(current, Tag): del current.contents[:] current.parent = None current.previous = None current.previousSibling = None current.next = None current.nextSibling = None current = next def prettify(self, encoding=DEFAULT_OUTPUT_ENCODING): return self.__str__(encoding, True) def renderContents(self, encoding=DEFAULT_OUTPUT_ENCODING, prettyPrint=False, indentLevel=0): """Renders the contents of this tag as a string in the given encoding. If encoding is None, returns a Unicode string..""" s = [] for c in self: text = None if isinstance(c, NavigableString): text = c.__str__(encoding) elif isinstance(c, Tag): s.append(c.__str__(encoding, prettyPrint, indentLevel)) if text and prettyPrint: text = text.strip() if text: if prettyPrint: s.append(" " * (indentLevel - 1)) s.append(text) if prettyPrint: s.append("\n") return ''.join(s) # Soup methods def find(self, name=None, attrs={}, recursive=True, text=None, **kwargs): """Return only the first child of this Tag matching the given criteria.""" r = None l = self.findAll(name, attrs, recursive, text, 1, **kwargs) if l: r = l[0] return r findChild = find def findAll(self, name=None, attrs={}, recursive=True, text=None, limit=None, **kwargs): """Extracts a list of Tag objects that match the given criteria. You can specify the name of the Tag and any attributes you want the Tag to have. The value of a key-value pair in the 'attrs' map can be a string, a list of strings, a regular expression object, or a callable that takes a string and returns whether or not the string matches for some custom definition of 'matches'. The same is true of the tag name.""" generator = self.recursiveChildGenerator if not recursive: generator = self.childGenerator return self._findAll(name, attrs, text, limit, generator, **kwargs) findChildren = findAll # Pre-3.x compatibility methods first = find fetch = findAll def fetchText(self, text=None, recursive=True, limit=None): return self.findAll(text=text, recursive=recursive, limit=limit) def firstText(self, text=None, recursive=True): return self.find(text=text, recursive=recursive) # Private methods def _getAttrMap(self): """Initializes a map representation of this tag's attributes, if not already initialized.""" if not getattr(self, 'attrMap'): self.attrMap = {} for (key, value) in self.attrs: self.attrMap[key] = value return self.attrMap # Generator methods def childGenerator(self): # Just use the iterator from the contents return iter(self.contents) def recursiveChildGenerator(self): if not len(self.contents): raise StopIteration stopNode = self._lastRecursiveChild().next current = self.contents[0] while current is not stopNode: yield current current = current.next # Next, a couple classes to represent queries and their results. class SoupStrainer: """Encapsulates a number of ways of matching a markup element (tag or text).""" def __init__(self, name=None, attrs={}, text=None, **kwargs): self.name = name if isinstance(attrs, basestring): kwargs['class'] = _match_css_class(attrs) attrs = None if kwargs: if attrs: attrs = attrs.copy() attrs.update(kwargs) else: attrs = kwargs self.attrs = attrs self.text = text def __str__(self): if self.text: return self.text else: return "%s|%s" % (self.name, self.attrs) def searchTag(self, markupName=None, markupAttrs={}): found = None markup = None if isinstance(markupName, Tag): markup = markupName markupAttrs = markup callFunctionWithTagData = callable(self.name) \ and not isinstance(markupName, Tag) if (not self.name) \ or callFunctionWithTagData \ or (markup and self._matches(markup, self.name)) \ or (not markup and self._matches(markupName, self.name)): if callFunctionWithTagData: match = self.name(markupName, markupAttrs) else: match = True markupAttrMap = None for attr, matchAgainst in self.attrs.items(): if not markupAttrMap: if hasattr(markupAttrs, 'get'): markupAttrMap = markupAttrs else: markupAttrMap = {} for k, v in markupAttrs: markupAttrMap[k] = v attrValue = markupAttrMap.get(attr) if not self._matches(attrValue, matchAgainst): match = False break if match: if markup: found = markup else: found = markupName return found def search(self, markup): # print 'looking for %s in %s' % (self, markup) found = None # If given a list of items, scan it for a text element that # matches. if hasattr(markup, "__iter__") \ and not isinstance(markup, Tag): for element in markup: if isinstance(element, NavigableString) \ and self.search(element): found = element break # If it's a Tag, make sure its name or attributes match. # Don't bother with Tags if we're searching for text. elif isinstance(markup, Tag): if not self.text: found = self.searchTag(markup) # If it's text, make sure the text matches. elif isinstance(markup, NavigableString) or \ isinstance(markup, basestring): if self._matches(markup, self.text): found = markup else: raise Exception, "I don't know how to match against a %s" \ % markup.__class__ return found def _matches(self, markup, matchAgainst): # print "Matching %s against %s" % (markup, matchAgainst) result = False if matchAgainst is True: result = markup is not None elif callable(matchAgainst): result = matchAgainst(markup) else: # Custom match methods take the tag as an argument, but all # other ways of matching match the tag name as a string. if isinstance(markup, Tag): markup = markup.name if markup and not isinstance(markup, basestring): markup = unicode(markup) # Now we know that chunk is either a string, or None. if hasattr(matchAgainst, 'match'): # It's a regexp object. result = markup and matchAgainst.search(markup) elif hasattr(matchAgainst, '__iter__'): # list-like result = markup in matchAgainst elif hasattr(matchAgainst, 'items'): result = markup.has_key(matchAgainst) elif matchAgainst and isinstance(markup, basestring): if isinstance(markup, unicode): matchAgainst = unicode(matchAgainst) else: matchAgainst = str(matchAgainst) if not result: result = matchAgainst == markup return result class ResultSet(list): """A ResultSet is just a list that keeps track of the SoupStrainer that created it.""" def __init__(self, source): list.__init__([]) self.source = source # Now, some helper functions. def buildTagMap(default, *args): """Turns a list of maps, lists, or scalars into a single map. Used to build the SELF_CLOSING_TAGS, NESTABLE_TAGS, and NESTING_RESET_TAGS maps out of lists and partial maps.""" built = {} for portion in args: if hasattr(portion, 'items'): # It's a map. Merge it. for k, v in portion.items(): built[k] = v elif hasattr(portion, '__iter__'): # is a list # It's a list. Map each item to the default. for k in portion: built[k] = default else: # It's a scalar. Map it to the default. built[portion] = default return built # Now, the parser classes. class BeautifulStoneSoup(Tag, SGMLParser): """This class contains the basic parser and search code. It defines a parser that knows nothing about tag behavior except for the following: You can't close a tag without closing all the tags it encloses. That is, "" actually means "". [Another possible explanation is "", but since this class defines no SELF_CLOSING_TAGS, it will never use that explanation.] This class is useful for parsing XML or made-up markup languages, or when BeautifulSoup makes an assumption counter to what you were expecting.""" SELF_CLOSING_TAGS = {} NESTABLE_TAGS = {} RESET_NESTING_TAGS = {} QUOTE_TAGS = {} PRESERVE_WHITESPACE_TAGS = [] MARKUP_MASSAGE = [(re.compile('(<[^<>]*)/>'), lambda x: x.group(1) + ' />'), (re.compile(']*)>'), lambda x: '') ] ROOT_TAG_NAME = u'[document]' HTML_ENTITIES = "html" XML_ENTITIES = "xml" XHTML_ENTITIES = "xhtml" # This only exists for backwards-compatibility ALL_ENTITIES = XHTML_ENTITIES # Used when determining whether a text node is all whitespace and # can be replaced with a single space. A text node that contains # fancy Unicode spaces (usually non-breaking) should be left # alone. STRIP_ASCII_SPACES = {9: None, 10: None, 12: None, 13: None, 32: None, } def __init__(self, markup="", parseOnlyThese=None, fromEncoding=None, markupMassage=True, smartQuotesTo=XML_ENTITIES, convertEntities=None, selfClosingTags=None, isHTML=False): """The Soup object is initialized as the 'root tag', and the provided markup (which can be a string or a file-like object) is fed into the underlying parser. sgmllib will process most bad HTML, and the BeautifulSoup class has some tricks for dealing with some HTML that kills sgmllib, but Beautiful Soup can nonetheless choke or lose data if your data uses self-closing tags or declarations incorrectly. By default, Beautiful Soup uses regexes to sanitize input, avoiding the vast majority of these problems. If the problems don't apply to you, pass in False for markupMassage, and you'll get better performance. The default parser massage techniques fix the two most common instances of invalid HTML that choke sgmllib:
(No space between name of closing tag and tag close) (Extraneous whitespace in declaration) You can pass in a custom list of (RE object, replace method) tuples to get Beautiful Soup to scrub your input the way you want.""" self.parseOnlyThese = parseOnlyThese self.fromEncoding = fromEncoding self.smartQuotesTo = smartQuotesTo self.convertEntities = convertEntities # Set the rules for how we'll deal with the entities we # encounter if self.convertEntities: # It doesn't make sense to convert encoded characters to # entities even while you're converting entities to Unicode. # Just convert it all to Unicode. self.smartQuotesTo = None if convertEntities == self.HTML_ENTITIES: self.convertXMLEntities = False self.convertHTMLEntities = True self.escapeUnrecognizedEntities = True elif convertEntities == self.XHTML_ENTITIES: self.convertXMLEntities = True self.convertHTMLEntities = True self.escapeUnrecognizedEntities = False elif convertEntities == self.XML_ENTITIES: self.convertXMLEntities = True self.convertHTMLEntities = False self.escapeUnrecognizedEntities = False else: self.convertXMLEntities = False self.convertHTMLEntities = False self.escapeUnrecognizedEntities = False self.instanceSelfClosingTags = buildTagMap(None, selfClosingTags) SGMLParser.__init__(self) if hasattr(markup, 'read'): # It's a file-type object. markup = markup.read() self.markup = markup self.markupMassage = markupMassage try: self._feed(isHTML=isHTML) except StopParsing: pass self.markup = None # The markup can now be GCed def convert_charref(self, name): """This method fixes a bug in Python's SGMLParser.""" try: n = int(name) except ValueError: return if not 0 <= n <= 127: # ASCII ends at 127, not 255 return return self.convert_codepoint(n) def _feed(self, inDocumentEncoding=None, isHTML=False): # Convert the document to Unicode. markup = self.markup if isinstance(markup, unicode): if not hasattr(self, 'originalEncoding'): self.originalEncoding = None else: dammit = UnicodeDammit \ (markup, [self.fromEncoding, inDocumentEncoding], smartQuotesTo=self.smartQuotesTo, isHTML=isHTML) markup = dammit.unicode self.originalEncoding = dammit.originalEncoding self.declaredHTMLEncoding = dammit.declaredHTMLEncoding if markup: if self.markupMassage: if not hasattr(self.markupMassage, "__iter__"): self.markupMassage = self.MARKUP_MASSAGE for fix, m in self.markupMassage: markup = fix.sub(m, markup) # We get rid of markupMassage so that the # soup object can be deepcopied later on. Some # Python installations can't copy regexes. If anyone # was relying on the existence of markupMassage, this # might cause problems. del (self.markupMassage) self.reset() SGMLParser.feed(self, markup) # Close out any unfinished strings and close all the open tags. self.endData() while self.currentTag.name != self.ROOT_TAG_NAME: self.popTag() def __getattr__(self, methodName): """This method routes method call requests to either the SGMLParser superclass or the Tag superclass, depending on the method name.""" # print "__getattr__ called on %s.%s" % (self.__class__, methodName) if methodName.startswith('start_') or methodName.startswith('end_') \ or methodName.startswith('do_'): return SGMLParser.__getattr__(self, methodName) elif not methodName.startswith('__'): return Tag.__getattr__(self, methodName) else: raise AttributeError def isSelfClosingTag(self, name): """Returns true iff the given string is the name of a self-closing tag according to this parser.""" return self.SELF_CLOSING_TAGS.has_key(name) \ or self.instanceSelfClosingTags.has_key(name) def reset(self): Tag.__init__(self, self, self.ROOT_TAG_NAME) self.hidden = 1 SGMLParser.reset(self) self.currentData = [] self.currentTag = None self.tagStack = [] self.quoteStack = [] self.pushTag(self) def popTag(self): tag = self.tagStack.pop() # print "Pop", tag.name if self.tagStack: self.currentTag = self.tagStack[-1] return self.currentTag def pushTag(self, tag): # print "Push", tag.name if self.currentTag: self.currentTag.contents.append(tag) self.tagStack.append(tag) self.currentTag = self.tagStack[-1] def endData(self, containerClass=NavigableString): if self.currentData: currentData = u''.join(self.currentData) if (currentData.translate(self.STRIP_ASCII_SPACES) == '' and not set([tag.name for tag in self.tagStack]).intersection( self.PRESERVE_WHITESPACE_TAGS)): if '\n' in currentData: currentData = '\n' else: currentData = ' ' self.currentData = [] if self.parseOnlyThese and len(self.tagStack) <= 1 and \ (not self.parseOnlyThese.text or \ not self.parseOnlyThese.search(currentData)): return o = containerClass(currentData) o.setup(self.currentTag, self.previous) if self.previous: self.previous.next = o self.previous = o self.currentTag.contents.append(o) def _popToTag(self, name, inclusivePop=True): """Pops the tag stack up to and including the most recent instance of the given tag. If inclusivePop is false, pops the tag stack up to but *not* including the most recent instqance of the given tag.""" # print "Popping to %s" % name if name == self.ROOT_TAG_NAME: return numPops = 0 mostRecentTag = None for i in range(len(self.tagStack) - 1, 0, -1): if name == self.tagStack[i].name: numPops = len(self.tagStack) - i break if not inclusivePop: numPops = numPops - 1 for i in range(0, numPops): mostRecentTag = self.popTag() return mostRecentTag def _smartPop(self, name): """We need to pop up to the previous tag of this type, unless one of this tag's nesting reset triggers comes between this tag and the previous tag of this type, OR unless this tag is a generic nesting trigger and another generic nesting trigger comes between this tag and the previous tag of this type. Examples:

FooBar *

* should pop to 'p', not 'b'.

FooBar *

* should pop to 'table', not 'p'.

Foo

Bar *

* should pop to 'tr', not 'p'.

    • *
    • * should pop to 'ul', not the first 'li'.
    • ** should pop to 'table', not the first 'tr' tag should implicitly close the previous tag within the same
    ** should pop to 'tr', not the first 'td' """ nestingResetTriggers = self.NESTABLE_TAGS.get(name) isNestable = nestingResetTriggers != None isResetNesting = self.RESET_NESTING_TAGS.has_key(name) popTo = None inclusive = True for i in range(len(self.tagStack) - 1, 0, -1): p = self.tagStack[i] if (not p or p.name == name) and not isNestable: # Non-nestable tags get popped to the top or to their # last occurance. popTo = name break if (nestingResetTriggers is not None and p.name in nestingResetTriggers) \ or (nestingResetTriggers is None and isResetNesting and self.RESET_NESTING_TAGS.has_key(p.name)): # If we encounter one of the nesting reset triggers # peculiar to this tag, or we encounter another tag # that causes nesting to reset, pop up to but not # including that tag. popTo = p.name inclusive = False break p = p.parent if popTo: self._popToTag(popTo, inclusive) def unknown_starttag(self, name, attrs, selfClosing=0): # print "Start tag %s: %s" % (name, attrs) if self.quoteStack: # This is not a real tag. # print "<%s> is not real!" % name attrs = ''.join([' %s="%s"' % (x, y) for x, y in attrs]) self.handle_data('<%s%s>' % (name, attrs)) return self.endData() if not self.isSelfClosingTag(name) and not selfClosing: self._smartPop(name) if self.parseOnlyThese and len(self.tagStack) <= 1 \ and (self.parseOnlyThese.text or not self.parseOnlyThese.searchTag(name, attrs)): return tag = Tag(self, name, attrs, self.currentTag, self.previous) if self.previous: self.previous.next = tag self.previous = tag self.pushTag(tag) if selfClosing or self.isSelfClosingTag(name): self.popTag() if name in self.QUOTE_TAGS: # print "Beginning quote (%s)" % name self.quoteStack.append(name) self.literal = 1 return tag def unknown_endtag(self, name): # print "End tag %s" % name if self.quoteStack and self.quoteStack[-1] != name: # This is not a real end tag. # print " is not real!" % name self.handle_data('' % name) return self.endData() self._popToTag(name) if self.quoteStack and self.quoteStack[-1] == name: self.quoteStack.pop() self.literal = (len(self.quoteStack) > 0) def handle_data(self, data): self.currentData.append(data) def _toStringSubclass(self, text, subclass): """Adds a certain piece of text to the tree as a NavigableString subclass.""" self.endData() self.handle_data(text) self.endData(subclass) def handle_pi(self, text): """Handle a processing instruction as a ProcessingInstruction object, possibly one with a %SOUP-ENCODING% slot into which an encoding will be plugged later.""" if text[:3] == "xml": text = u"xml version='1.0' encoding='%SOUP-ENCODING%'" self._toStringSubclass(text, ProcessingInstruction) def handle_comment(self, text): "Handle comments as Comment objects." self._toStringSubclass(text, Comment) def handle_charref(self, ref): "Handle character references as data." if self.convertEntities: data = unichr(int(ref)) else: data = '&#%s;' % ref self.handle_data(data) def handle_entityref(self, ref): """Handle entity references as data, possibly converting known HTML and/or XML entity references to the corresponding Unicode characters.""" data = None if self.convertHTMLEntities: try: data = unichr(name2codepoint[ref]) except KeyError: pass if not data and self.convertXMLEntities: data = self.XML_ENTITIES_TO_SPECIAL_CHARS.get(ref) if not data and self.convertHTMLEntities and \ not self.XML_ENTITIES_TO_SPECIAL_CHARS.get(ref): # We've got a problem here. We're told this is # an entity reference, but it's not an XML entity # reference or an HTML entity reference. Nonetheless, # the logical thing to do is to pass it through as an # unrecognized entity reference. # # Except: when the input is "&carol;" this function # will be called with input "carol". When the input is # "AT&T", this function will be called with input # "T". We have no way of knowing whether a semicolon # was present originally, so we don't know whether # this is an unknown entity or just a misplaced # ampersand. # # The more common case is a misplaced ampersand, so I # escape the ampersand and omit the trailing semicolon. data = "&%s" % ref if not data: # This case is different from the one above, because we # haven't already gone through a supposedly comprehensive # mapping of entities to Unicode characters. We might not # have gone through any mapping at all. So the chances are # very high that this is a real entity, and not a # misplaced ampersand. data = "&%s;" % ref self.handle_data(data) def handle_decl(self, data): "Handle DOCTYPEs and the like as Declaration objects." self._toStringSubclass(data, Declaration) def parse_declaration(self, i): """Treat a bogus SGML declaration as raw data. Treat a CDATA declaration as a CData object.""" j = None if self.rawdata[i:i + 9] == '', i) if k == -1: k = len(self.rawdata) data = self.rawdata[i + 9:k] j = k + 3 self._toStringSubclass(data, CData) else: try: j = SGMLParser.parse_declaration(self, i) except SGMLParseError: toHandle = self.rawdata[i:] self.handle_data(toHandle) j = i + len(toHandle) return j class BeautifulSoup(BeautifulStoneSoup): """This parser knows the following facts about HTML: * Some tags have no closing tag and should be interpreted as being closed as soon as they are encountered. * The text inside some tags (ie. 'script') may contain tags which are not really part of the document and which should be parsed as text, not tags. If you want to parse the text as tags, you can always fetch it and parse it explicitly. * Tag nesting rules: Most tags can't be nested at all. For instance, the occurance of a

    tag should implicitly close the previous

    tag.

    Para1

    Para2 should be transformed into:

    Para1

    Para2 Some tags can be nested arbitrarily. For instance, the occurance of a

    tag should _not_ implicitly close the previous
    tag. Alice said:
    Bob said:
    Blah should NOT be transformed into: Alice said:
    Bob said:
    Blah Some tags can be nested, but the nesting is reset by the interposition of other tags. For instance, a
    , but not close a tag in another table.
    BlahBlah should be transformed into:
    BlahBlah but, Blah
    Blah should NOT be transformed into Blah
    Blah Differing assumptions about tag nesting rules are a major source of problems with the BeautifulSoup class. If BeautifulSoup is not treating as nestable a tag your page author treats as nestable, try ICantBelieveItsBeautifulSoup, MinimalSoup, or BeautifulStoneSoup before writing your own subclass.""" def __init__(self, *args, **kwargs): if not kwargs.has_key('smartQuotesTo'): kwargs['smartQuotesTo'] = self.HTML_ENTITIES kwargs['isHTML'] = True BeautifulStoneSoup.__init__(self, *args, **kwargs) SELF_CLOSING_TAGS = buildTagMap(None, ('br', 'hr', 'input', 'img', 'meta', 'spacer', 'link', 'frame', 'base', 'col')) PRESERVE_WHITESPACE_TAGS = set(['pre', 'textarea']) QUOTE_TAGS = {'script': None, 'textarea': None} # According to the HTML standard, each of these inline tags can # contain another tag of the same type. Furthermore, it's common # to actually use these tags this way. NESTABLE_INLINE_TAGS = ('span', 'font', 'q', 'object', 'bdo', 'sub', 'sup', 'center') # According to the HTML standard, these block tags can contain # another tag of the same type. Furthermore, it's common # to actually use these tags this way. NESTABLE_BLOCK_TAGS = ('blockquote', 'div', 'fieldset', 'ins', 'del') # Lists can contain other lists, but there are restrictions. NESTABLE_LIST_TAGS = {'ol': [], 'ul': [], 'li': ['ul', 'ol'], 'dl': [], 'dd': ['dl'], 'dt': ['dl']} # Tables can contain other tables, but there are restrictions. NESTABLE_TABLE_TAGS = {'table': [], 'tr': ['table', 'tbody', 'tfoot', 'thead'], 'td': ['tr'], 'th': ['tr'], 'thead': ['table'], 'tbody': ['table'], 'tfoot': ['table'], } NON_NESTABLE_BLOCK_TAGS = ('address', 'form', 'p', 'pre') # If one of these tags is encountered, all tags up to the next tag of # this type are popped. RESET_NESTING_TAGS = buildTagMap(None, NESTABLE_BLOCK_TAGS, 'noscript', NON_NESTABLE_BLOCK_TAGS, NESTABLE_LIST_TAGS, NESTABLE_TABLE_TAGS) NESTABLE_TAGS = buildTagMap([], NESTABLE_INLINE_TAGS, NESTABLE_BLOCK_TAGS, NESTABLE_LIST_TAGS, NESTABLE_TABLE_TAGS) # Used to detect the charset in a META tag; see start_meta CHARSET_RE = re.compile("((^|;)\s*charset=)([^;]*)", re.M) def start_meta(self, attrs): """Beautiful Soup can detect a charset included in a META tag, try to convert the document to that charset, and re-parse the document from the beginning.""" httpEquiv = None contentType = None contentTypeIndex = None tagNeedsEncodingSubstitution = False for i in range(0, len(attrs)): key, value = attrs[i] key = key.lower() if key == 'http-equiv': httpEquiv = value elif key == 'content': contentType = value contentTypeIndex = i if httpEquiv and contentType: # It's an interesting meta tag. match = self.CHARSET_RE.search(contentType) if match: if (self.declaredHTMLEncoding is not None or self.originalEncoding == self.fromEncoding): # An HTML encoding was sniffed while converting # the document to Unicode, or an HTML encoding was # sniffed during a previous pass through the # document, or an encoding was specified # explicitly and it worked. Rewrite the meta tag. def rewrite(match): return match.group(1) + "%SOUP-ENCODING%" newAttr = self.CHARSET_RE.sub(rewrite, contentType) attrs[contentTypeIndex] = (attrs[contentTypeIndex][0], newAttr) tagNeedsEncodingSubstitution = True else: # This is our first pass through the document. # Go through it again with the encoding information. newCharset = match.group(3) if newCharset and newCharset != self.originalEncoding: self.declaredHTMLEncoding = newCharset self._feed(self.declaredHTMLEncoding) raise StopParsing pass tag = self.unknown_starttag("meta", attrs) if tag and tagNeedsEncodingSubstitution: tag.containsSubstitutions = True class StopParsing(Exception): pass class ICantBelieveItsBeautifulSoup(BeautifulSoup): """The BeautifulSoup class is oriented towards skipping over common HTML errors like unclosed tags. However, sometimes it makes errors of its own. For instance, consider this fragment: FooBar This is perfectly valid (if bizarre) HTML. However, the BeautifulSoup class will implicitly close the first b tag when it encounters the second 'b'. It will think the author wrote "FooBar", and didn't close the first 'b' tag, because there's no real-world reason to bold something that's already bold. When it encounters '' it will close two more 'b' tags, for a grand total of three tags closed instead of two. This can throw off the rest of your document structure. The same is true of a number of other tags, listed below. It's much more common for someone to forget to close a 'b' tag than to actually use nested 'b' tags, and the BeautifulSoup class handles the common case. This class handles the not-co-common case: where you can't believe someone wrote what they did, but it's valid HTML and BeautifulSoup screwed up by assuming it wouldn't be.""" I_CANT_BELIEVE_THEYRE_NESTABLE_INLINE_TAGS = \ ('em', 'big', 'i', 'small', 'tt', 'abbr', 'acronym', 'strong', 'cite', 'code', 'dfn', 'kbd', 'samp', 'strong', 'var', 'b', 'big') I_CANT_BELIEVE_THEYRE_NESTABLE_BLOCK_TAGS = ('noscript',) NESTABLE_TAGS = buildTagMap([], BeautifulSoup.NESTABLE_TAGS, I_CANT_BELIEVE_THEYRE_NESTABLE_BLOCK_TAGS, I_CANT_BELIEVE_THEYRE_NESTABLE_INLINE_TAGS) class MinimalSoup(BeautifulSoup): """The MinimalSoup class is for parsing HTML that contains pathologically bad markup. It makes no assumptions about tag nesting, but it does know which tags are self-closing, that