Beautiful Soup - "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
* cjkcodecs and iconv_codec, which add more encodings to the ones supported
- by stock Python.
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) 2004-2008, 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__ = "3.0.7a"
__copyright__ = "Copyright (c) 2004-2008 Leonard Richardson"
__license__ = "New-style BSD"
from sgmllib import SGMLParser, SGMLParseError
import codecs
import markupbase
import types
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"
# First, the classes that represent markup elements.
class PageElement:
"""Contains the navigational information for some part of the page
(either a tag or a piece of text)"""
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.contents.index(self)
if hasattr(replaceWith, 'parent') and replaceWith.parent == self.parent:
# We're replacing this element with one of its siblings.
index = self.parent.contents.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 extract(self):
"""Destructively rips this element out of the tree."""
if self.parent:
try:
self.parent.contents.remove(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)
or isinstance(newChild, unicode)) \
and not isinstance(newChild, NavigableString):
newChild = NavigableString(newChild)
position = min(position, len(self.contents))
if hasattr(newChild, 'parent') and newChild.parent != None:
# We're 'inserting' an element that's already one
# of this object's children.
if newChild.parent == self:
index = self.find(newChild)
if index and 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
else:
# Build a SoupStrainer
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:
i = i.next
yield i
def nextSiblingGenerator(self):
i = self
while i:
i = i.nextSibling
yield i
def previousGenerator(self):
i = self
while i:
i = i.previous
yield i
def previousSiblingGenerator(self):
i = self
while i:
i = i.previousSibling
yield i
def parentGenerator(self):
i = self
while i:
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
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):
if encoding:
return self.encode(encoding)
else:
return self
class CData(NavigableString):
def __str__(self, encoding=DEFAULT_OUTPUT_ENCODING):
return "<![CDATA[%s]]>" % 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 "<?%s?>" % self.toEncoding(output, encoding)
class Comment(NavigableString):
def __str__(self, encoding=DEFAULT_OUTPUT_ENCODING):
return "<!--%s-->" % NavigableString.__str__(self, encoding)
class Declaration(NavigableString):
def __str__(self, encoding=DEFAULT_OUTPUT_ENCODING):
return "<!%s>" % NavigableString.__str__(self, encoding)
class Tag(PageElement):
"""Represents a found HTML tag with its attributes and contents."""
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 _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 == None:
attrs = []
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 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 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 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)
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]] + ";"
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 isString(val):
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:
# TODO: 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 = '</%s>' % 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."""
contents = [i for i in self.contents]
for i in contents:
if isinstance(i, Tag):
i.decompose()
else:
i.extract()
self.extract()
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):
for i in range(0, len(self.contents)):
yield self.contents[i]
raise StopIteration
def recursiveChildGenerator(self):
stack = [(self, 0)]
while stack:
tag, start = stack.pop()
if isinstance(tag, Tag):
for i in range(start, len(tag.contents)):
a = tag.contents[i]
yield a
if isinstance(a, Tag) and tag.contents:
if i < len(tag.contents) - 1:
stack.append((tag, i+1))
stack.append((a, 0))
break
raise StopIteration
# 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 isString(attrs):
kwargs['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 isList(markup) 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 \
isString(markup):
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 == True and type(matchAgainst) == types.BooleanType:
result = markup != 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 isString(markup):
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 isList(matchAgainst):
result = markup in matchAgainst
elif hasattr(matchAgainst, 'items'):
result = markup.has_key(matchAgainst)
elif matchAgainst and isString(markup):
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 isList(l):
"""Convenience method that works with all 2.x versions of Python
to determine whether or not something is listlike."""
return hasattr(l, '__iter__') \
or (type(l) in (types.ListType, types.TupleType))
def isString(s):
"""Convenience method that works with all 2.x versions of Python
to determine whether or not something is stringlike."""
try:
return isinstance(s, unicode) or isinstance(s, basestring)
except NameError:
return isinstance(s, str)
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 isList(portion):
#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, "<foo><bar></foo>" actually means
"<foo><bar></bar></foo>".
[Another possible explanation is "<foo><bar /></foo>", 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('<!\s+([^<>]*)>'),
lambda x: '<!' + x.group(1) + '>')
]
ROOT_TAG_NAME = u'[document]'
HTML_ENTITIES = "html"
XML_ENTITIES = "xml"
XHTML_ENTITIES = "xhtml"
# TODO: 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:
<br/> (No space between name of closing tag and tag close)
<! --Comment--> (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 isList(self.markupMassage):
self.markupMassage = self.MARKUP_MASSAGE
for fix, m in self.markupMassage:
markup = fix.sub(m, markup)
# TODO: 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.find('start_') == 0 or methodName.find('end_') == 0 \
or methodName.find('do_') == 0:
return SGMLParser.__getattr__(self, methodName)
elif methodName.find('__') != 0:
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()
# Tags with just one string-owning child get the child as a
# 'string' property, so that soup.tag.string is shorthand for
# soup.tag.contents[0]
if len(self.currentTag.contents) == 1 and \
isinstance(self.currentTag.contents[0], NavigableString):
self.currentTag.string = self.currentTag.contents[0]
#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:
<p>Foo<b>Bar *<p>* should pop to 'p', not 'b'.
<p>Foo<table>Bar *<p>* should pop to 'table', not 'p'.
<p>Foo<table><tr>Bar *<p>* should pop to 'tr', not 'p'.
<li><ul><li> *<li>* should pop to 'ul', not the first 'li'.
<tr><table><tr> *<tr>* should pop to 'table', not the first 'tr'
<td><tr><td> *<td>* 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 != None
and p.name in nestingResetTriggers) \
or (nestingResetTriggers == 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(map(lambda(x, y): ' %s="%s"' % (x, y), 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 "</%s> is not real!" % name
self.handle_data('</%s>' % 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):
# TODO: 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] == '<![CDATA[':
k = self.rawdata.find(']]>', 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 <p> tag should implicitly close the previous <p> tag.
<p>Para1<p>Para2
should be transformed into:
<p>Para1</p><p>Para2
Some tags can be nested arbitrarily. For instance, the occurance
of a <blockquote> tag should _not_ implicitly close the previous
<blockquote> tag.
Alice said: <blockquote>Bob said: <blockquote>Blah
should NOT be transformed into:
Alice said: <blockquote>Bob said: </blockquote><blockquote>Blah
Some tags can be nested, but the nesting is reset by the
interposition of other tags. For instance, a <tr> tag should
implicitly close the previous <tr> tag within the same <table>,
but not close a <tr> tag in another table.
<table><tr>Blah<tr>Blah
should be transformed into:
<table><tr>Blah</tr><tr>Blah
but,
<tr>Blah<table><tr>Blah
should NOT be transformed into
<tr>Blah<table></tr><tr>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'])
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:
<b>Foo<b>Bar</b></b>
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
"<b>Foo<b>Bar", 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 '</b></b>' 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
<script> tags contain Javascript and should not be parsed, that
META tags may contain encoding information, and so on.
This also makes it better for subclassing than BeautifulStoneSoup
or BeautifulSoup."""
RESET_NESTING_TAGS = buildTagMap('noscript')
NESTABLE_TAGS = {}
class BeautifulSOAP(BeautifulStoneSoup):
"""This class will push a tag with only a single string child into
the tag's parent as an attribute. The attribute's name is the tag
name, and the value is the string child. An example should give
the flavor of the change:
<foo><bar>baz</bar></foo>
=>
<foo bar="baz"><bar>baz</bar></foo>
You can then access fooTag['bar'] instead of fooTag.barTag.string.
This is, of course, useful for scraping structures that tend to
use subelements instead of attributes, such as SOAP messages. Note
that it modifies its input, so don't print the modified version
out.
I'm not sure how many people really want to use this class; let me
know if you do. Mainly I like the name."""
def popTag(self):
if len(self.tagStack) > 1:
tag = self.tagStack[-1]
parent = self.tagStack[-2]
parent._getAttrMap()
if (isinstance(tag, Tag) and len(tag.contents) == 1 and
isinstance(tag.contents[0], NavigableString) and
not parent.attrMap.has_key(tag.name)):
parent[tag.name] = tag.contents[0]
BeautifulStoneSoup.popTag(self)
#Enterprise class names! It has come to our attention that some people
#think the names of the Beautiful Soup parser classes are too silly
#and "unprofessional" for use in enterprise screen-scraping. We feel
#your pain! For such-minded folk, the Beautiful Soup Consortium And
#All-Night Kosher Bakery recommends renaming this file to
#"RobustParser.py" (or, in cases of extreme enterprisiness,
#"RobustParserBeanInterface.class") and using the following
#enterprise-friendly class aliases:
class RobustXMLParser(BeautifulStoneSoup):
pass
class RobustHTMLParser(BeautifulSoup):
pass
class RobustWackAssHTMLParser(ICantBelieveItsBeautifulSoup):
pass
class RobustInsanelyWackAssHTMLParser(MinimalSoup):
pass
class SimplifyingSOAPParser(BeautifulSOAP):
pass
######################################################
#
# Bonus library: Unicode, Dammit
#
# This class forces XML data into a standard format (usually to UTF-8
# or Unicode). It is heavily based on code from Mark Pilgrim's
# Universal Feed Parser. It does not rewrite the XML or HTML to
# reflect a new encoding: that happens in BeautifulStoneSoup.handle_pi
# (XML) and BeautifulSoup.start_meta (HTML).
# Autodetects character encodings.
# Download from http://chardet.feedparser.org/
try:
import chardet
# import chardet.constants
# chardet.constants._debug = 1
except ImportError:
chardet = None
# cjkcodecs and iconv_codec make Python know about more character encodings.
# Both are available from http://cjkpython.i18n.org/
# They're built in if you use Python 2.4.
try:
import cjkcodecs.aliases
except ImportError:
pass
try:
import iconv_codec
except ImportError:
pass
class UnicodeDammit:
"""A class for detecting the encoding of a *ML document and
converting it to a Unicode string. If the source encoding is
windows-1252, can replace MS smart quotes with their HTML or XML
equivalents."""
# This dictionary maps commonly seen values for "charset" in HTML
# meta tags to the corresponding Python codec names. It only covers
# values that aren't in Python's aliases and can't be determined
# by the heuristics in find_codec.
CHARSET_ALIASES = { "macintosh" : "mac-roman",
"x-sjis" : "shift-jis" }
def __init__(self, markup, overrideEncodings=[],
smartQuotesTo='xml', isHTML=False):
self.declaredHTMLEncoding = None
self.markup, documentEncoding, sniffedEncoding = \
self._detectEncoding(markup, isHTML)
self.smartQuotesTo = smartQuotesTo
self.triedEncodings = []
if markup == '' or isinstance(markup, unicode):
self.originalEncoding = None
self.unicode = unicode(markup)
return
u = None
for proposedEncoding in overrideEncodings:
u = self._convertFrom(proposedEncoding)
if u: break
if not u:
for proposedEncoding in (documentEncoding, sniffedEncoding):
u = self._convertFrom(proposedEncoding)
if u: break
# If no luck and we have auto-detection library, try that:
if not u and chardet and not isinstance(self.markup, unicode):
u = self._convertFrom(chardet.detect(self.markup)['encoding'])
# As a last resort, try utf-8 and windows-1252:
if not u:
for proposed_encoding in ("utf-8", "windows-1252"):
u = self._convertFrom(proposed_encoding)
if u: break
self.unicode = u
if not u: self.originalEncoding = None
def _subMSChar(self, orig):
"""Changes a MS smart quote character to an XML or HTML
entity."""
sub = self.MS_CHARS.get(orig)
if type(sub) == types.TupleType:
if self.smartQuotesTo == 'xml':
sub = '&#x%s;' % sub[1]
else:
sub = '&%s;' % sub[0]
return sub
def _convertFrom(self, proposed):
proposed = self.find_codec(proposed)
if not proposed or proposed in self.triedEncodings:
return None
self.triedEncodings.append(proposed)
markup = self.markup
# Convert smart quotes to HTML if coming from an encoding
# that might have them.
if self.smartQuotesTo and proposed.lower() in("windows-1252",
"iso-8859-1",
"iso-8859-2"):
markup = re.compile("([\x80-\x9f])").sub \
(lambda(x): self._subMSChar(x.group(1)),
markup)
try:
# print "Trying to convert document to %s" % proposed
u = self._toUnicode(markup, proposed)
self.markup = u
self.originalEncoding = proposed
except Exception, e:
# print "That didn't work!"
# print e
return None
#print "Correct encoding: %s" % proposed
return self.markup
def _toUnicode(self, data, encoding):
'''Given a string and its encoding, decodes the string into Unicode.
%encoding is a string recognized by encodings.aliases'''
# strip Byte Order Mark (if present)
if (len(data) >= 4) and (data[:2] == '\xfe\xff') \
and (data[2:4] != '\x00\x00'):
encoding = 'utf-16be'
data = data[2:]
elif (len(data) >= 4) and (data[:2] == '\xff\xfe') \
and (data[2:4] != '\x00\x00'):
encoding = 'utf-16le'
data = data[2:]
elif data[:3] == '\xef\xbb\xbf':
encoding = 'utf-8'
data = data[3:]
elif data[:4] == '\x00\x00\xfe\xff':
encoding = 'utf-32be'
data = data[4:]
elif data[:4] == '\xff\xfe\x00\x00':
encoding = 'utf-32le'
data = data[4:]
newdata = unicode(data, encoding)
return newdata
def _detectEncoding(self, xml_data, isHTML=False):
"""Given a document, tries to detect its XML encoding."""
xml_encoding = sniffed_xml_encoding = None
try:
if xml_data[:4] == '\x4c\x6f\xa7\x94':
# EBCDIC
xml_data = self._ebcdic_to_ascii(xml_data)
elif xml_data[:4] == '\x00\x3c\x00\x3f':
# UTF-16BE
sniffed_xml_encoding = 'utf-16be'
xml_data = unicode(xml_data, 'utf-16be').encode('utf-8')
elif (len(xml_data) >= 4) and (xml_data[:2] == '\xfe\xff') \
and (xml_data[2:4] != '\x00\x00'):
# UTF-16BE with BOM
sniffed_xml_encoding = 'utf-16be'
xml_data = unicode(xml_data[2:], 'utf-16be').encode('utf-8')
elif xml_data[:4] == '\x3c\x00\x3f\x00':
# UTF-16LE
sniffed_xml_encoding = 'utf-16le'
xml_data = unicode(xml_data, 'utf-16le').encode('utf-8')
elif (len(xml_data) >= 4) and (xml_data[:2] == '\xff\xfe') and \
(xml_data[2:4] != '\x00\x00'):
# UTF-16LE with BOM
sniffed_xml_encoding = 'utf-16le'
xml_data = unicode(xml_data[2:], 'utf-16le').encode('utf-8')
elif xml_data[:4] == '\x00\x00\x00\x3c':
# UTF-32BE
sniffed_xml_encoding = 'utf-32be'
xml_data = unicode(xml_data, 'utf-32be').encode('utf-8')
elif xml_data[:4] == '\x3c\x00\x00\x00':
# UTF-32LE
sniffed_xml_encoding = 'utf-32le'
xml_data = unicode(xml_data, 'utf-32le').encode('utf-8')
elif xml_data[:4] == '\x00\x00\xfe\xff':
# UTF-32BE with BOM
sniffed_xml_encoding = 'utf-32be'
xml_data = unicode(xml_data[4:], 'utf-32be').encode('utf-8')
elif xml_data[:4] == '\xff\xfe\x00\x00':
# UTF-32LE with BOM
sniffed_xml_encoding = 'utf-32le'
xml_data = unicode(xml_data[4:], 'utf-32le').encode('utf-8')
elif xml_data[:3] == '\xef\xbb\xbf':
# UTF-8 with BOM
sniffed_xml_encoding = 'utf-8'
xml_data = unicode(xml_data[3:], 'utf-8').encode('utf-8')
else:
sniffed_xml_encoding = 'ascii'
pass
except:
xml_encoding_match = None
xml_encoding_match = re.compile(
'^<\?.*encoding=[\'"](.*?)[\'"].*\?>').match(xml_data)
if not xml_encoding_match and isHTML:
regexp = re.compile('<\s*meta[^>]+charset=([^>]*?)[;\'">]', re.I)
xml_encoding_match = regexp.search(xml_data)
if xml_encoding_match is not None:
xml_encoding = xml_encoding_match.groups()[0].lower()
if isHTML:
self.declaredHTMLEncoding = xml_encoding
if sniffed_xml_encoding and \
(xml_encoding in ('iso-10646-ucs-2', 'ucs-2', 'csunicode',
'iso-10646-ucs-4', 'ucs-4', 'csucs4',
'utf-16', 'utf-32', 'utf_16', 'utf_32',
'utf16', 'u16')):
xml_encoding = sniffed_xml_encoding
return xml_data, xml_encoding, sniffed_xml_encoding
def find_codec(self, charset):
return self._codec(self.CHARSET_ALIASES.get(charset, charset)) \
or (charset and self._codec(charset.replace("-", ""))) \
or (charset and self._codec(charset.replace("-", "_"))) \
or charset
def _codec(self, charset):
if not charset: return charset
codec = None
try:
codecs.lookup(charset)
codec = charset
except (LookupError, ValueError):
pass
return codec
EBCDIC_TO_ASCII_MAP = None
def _ebcdic_to_ascii(self, s):
c = self.__class__
if not c.EBCDIC_TO_ASCII_MAP:
emap = (0,1,2,3,156,9,134,127,151,141,142,11,12,13,14,15,
16,17,18,19,157,133,8,135,24,25,146,143,28,29,30,31,
128,129,130,131,132,10,23,27,136,137,138,139,140,5,6,7,
144,145,22,147,148,149,150,4,152,153,154,155,20,21,158,26,
32,160,161,162,163,164,165,166,167,168,91,46,60,40,43,33,
38,169,170,171,172,173,174,175,176,177,93,36,42,41,59,94,
45,47,178,179,180,181,182,183,184,185,124,44,37,95,62,63,
186,187,188,189,190,191,192,193,194,96,58,35,64,39,61,34,
195,97,98,99,100,101,102,103,104,105,196,197,198,199,200,
201,202,106,107,108,109,110,111,112,113,114,203,204,205,
206,207,208,209,126,115,116,117,118,119,120,121,122,210,
211,212,213,214,215,216,217,218,219,220,221,222,223,224,
225,226,227,228,229,230,231,123,65,66,67,68,69,70,71,72,
73,232,233,234,235,236,237,125,74,75,76,77,78,79,80,81,
82,238,239,240,241,242,243,92,159,83,84,85,86,87,88,89,
90,244,245,246,247,248,249,48,49,50,51,52,53,54,55,56,57,
250,251,252,253,254,255)
import string
c.EBCDIC_TO_ASCII_MAP = string.maketrans( \
''.join(map(chr, range(256))), ''.join(map(chr, emap)))
return s.translate(c.EBCDIC_TO_ASCII_MAP)
MS_CHARS = { '\x80' : ('euro', '20AC'),
'\x81' : ' ',
'\x82' : ('sbquo', '201A'),
'\x83' : ('fnof', '192'),
'\x84' : ('bdquo', '201E'),
'\x85' : ('hellip', '2026'),
'\x86' : ('dagger', '2020'),
'\x87' : ('Dagger', '2021'),
'\x88' : ('circ', '2C6'),
'\x89' : ('permil', '2030'),
'\x8A' : ('Scaron', '160'),
'\x8B' : ('lsaquo', '2039'),
'\x8C' : ('OElig', '152'),
'\x8D' : '?',
'\x8E' : ('#x17D', '17D'),
'\x8F' : '?',
'\x90' : '?',
'\x91' : ('lsquo', '2018'),
'\x92' : ('rsquo', '2019'),
'\x93' : ('ldquo', '201C'),
'\x94' : ('rdquo', '201D'),
'\x95' : ('bull', '2022'),
'\x96' : ('ndash', '2013'),
'\x97' : ('mdash', '2014'),
'\x98' : ('tilde', '2DC'),
'\x99' : ('trade', '2122'),
'\x9a' : ('scaron', '161'),
'\x9b' : ('rsaquo', '203A'),
'\x9c' : ('oelig', '153'),
'\x9d' : '?',
'\x9e' : ('#x17E', '17E'),
'\x9f' : ('Yuml', ''),}
#######################################################################
#By default, act as an HTML pretty-printer.
if __name__ == '__main__':
import sys
soup = BeautifulSoup(sys.stdin)
print soup.prettify()