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""" Use the HTMLParser library to parse HTML files that aren ' t too bad. """
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# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
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__all__ = [
' HTMLParserTreeBuilder ' ,
]
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from HTMLParser import HTMLParser
try :
from HTMLParser import HTMLParseError
except ImportError , e :
# HTMLParseError is removed in Python 3.5. Since it can never be
# thrown in 3.5, we can just define our own class as a placeholder.
class HTMLParseError ( Exception ) :
pass
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import sys
import warnings
# Starting in Python 3.2, the HTMLParser constructor takes a 'strict'
# argument, which we'd like to set to False. Unfortunately,
# http://bugs.python.org/issue13273 makes strict=True a better bet
# before Python 3.2.3.
#
# At the end of this file, we monkeypatch HTMLParser so that
# strict=True works well on Python 3.2.2.
major , minor , release = sys . version_info [ : 3 ]
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CONSTRUCTOR_TAKES_STRICT = major == 3 and minor == 2 and release > = 3
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CONSTRUCTOR_STRICT_IS_DEPRECATED = major == 3 and minor == 3
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CONSTRUCTOR_TAKES_CONVERT_CHARREFS = major == 3 and minor > = 4
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from bs4 . element import (
CData ,
Comment ,
Declaration ,
Doctype ,
ProcessingInstruction ,
)
from bs4 . dammit import EntitySubstitution , UnicodeDammit
from bs4 . builder import (
HTML ,
HTMLTreeBuilder ,
STRICT ,
)
HTMLPARSER = ' html.parser '
class BeautifulSoupHTMLParser ( HTMLParser ) :
def handle_starttag ( self , name , attrs ) :
# XXX namespace
attr_dict = { }
for key , value in attrs :
# Change None attribute values to the empty string
# for consistency with the other tree builders.
if value is None :
value = ' '
attr_dict [ key ] = value
attrvalue = ' " " '
self . soup . handle_starttag ( name , None , None , attr_dict )
def handle_endtag ( self , name ) :
self . soup . handle_endtag ( name )
def handle_data ( self , data ) :
self . soup . handle_data ( data )
def handle_charref ( self , name ) :
# XXX workaround for a bug in HTMLParser. Remove this once
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# it's fixed in all supported versions.
# http://bugs.python.org/issue13633
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if name . startswith ( ' x ' ) :
real_name = int ( name . lstrip ( ' x ' ) , 16 )
elif name . startswith ( ' X ' ) :
real_name = int ( name . lstrip ( ' X ' ) , 16 )
else :
real_name = int ( name )
try :
data = unichr ( real_name )
except ( ValueError , OverflowError ) , e :
data = u " \N{REPLACEMENT CHARACTER} "
self . handle_data ( data )
def handle_entityref ( self , name ) :
character = EntitySubstitution . HTML_ENTITY_TO_CHARACTER . get ( name )
if character is not None :
data = character
else :
data = " & %s ; " % name
self . handle_data ( data )
def handle_comment ( self , data ) :
self . soup . endData ( )
self . soup . handle_data ( data )
self . soup . endData ( Comment )
def handle_decl ( self , data ) :
self . soup . endData ( )
if data . startswith ( " DOCTYPE " ) :
data = data [ len ( " DOCTYPE " ) : ]
elif data == ' DOCTYPE ' :
# i.e. "<!DOCTYPE>"
data = ' '
self . soup . handle_data ( data )
self . soup . endData ( Doctype )
def unknown_decl ( self , data ) :
if data . upper ( ) . startswith ( ' CDATA[ ' ) :
cls = CData
data = data [ len ( ' CDATA[ ' ) : ]
else :
cls = Declaration
self . soup . endData ( )
self . soup . handle_data ( data )
self . soup . endData ( cls )
def handle_pi ( self , data ) :
self . soup . endData ( )
self . soup . handle_data ( data )
self . soup . endData ( ProcessingInstruction )
class HTMLParserTreeBuilder ( HTMLTreeBuilder ) :
is_xml = False
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picklable = True
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NAME = HTMLPARSER
features = [ NAME , HTML , STRICT ]
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def __init__ ( self , * args , * * kwargs ) :
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if CONSTRUCTOR_TAKES_STRICT and not CONSTRUCTOR_STRICT_IS_DEPRECATED :
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kwargs [ ' strict ' ] = False
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if CONSTRUCTOR_TAKES_CONVERT_CHARREFS :
kwargs [ ' convert_charrefs ' ] = False
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self . parser_args = ( args , kwargs )
def prepare_markup ( self , markup , user_specified_encoding = None ,
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document_declared_encoding = None , exclude_encodings = None ) :
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"""
: return : A 4 - tuple ( markup , original encoding , encoding
declared within markup , whether any characters had to be
replaced with REPLACEMENT CHARACTER ) .
"""
if isinstance ( markup , unicode ) :
yield ( markup , None , None , False )
return
try_encodings = [ user_specified_encoding , document_declared_encoding ]
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dammit = UnicodeDammit ( markup , try_encodings , is_html = True ,
exclude_encodings = exclude_encodings )
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yield ( dammit . markup , dammit . original_encoding ,
dammit . declared_html_encoding ,
dammit . contains_replacement_characters )
def feed ( self , markup ) :
args , kwargs = self . parser_args
parser = BeautifulSoupHTMLParser ( * args , * * kwargs )
parser . soup = self . soup
try :
parser . feed ( markup )
except HTMLParseError , e :
warnings . warn ( RuntimeWarning (
" Python ' s built-in HTMLParser cannot parse the given document. This is not a bug in Beautiful Soup. The best solution is to install an external parser (lxml or html5lib), and use Beautiful Soup with that parser. See http://www.crummy.com/software/BeautifulSoup/bs4/doc/#installing-a-parser for help. " ) )
raise e
# Patch 3.2 versions of HTMLParser earlier than 3.2.3 to use some
# 3.2.3 code. This ensures they don't treat markup like <p></p> as a
# string.
#
# XXX This code can be removed once most Python 3 users are on 3.2.3.
if major == 3 and minor == 2 and not CONSTRUCTOR_TAKES_STRICT :
import re
attrfind_tolerant = re . compile (
r ' \ s*((?<=[ \' " \ s])[^ \ s/>][^ \ s/=>]*)( \ s*=+ \ s* '
r ' ( \' [^ \' ]* \' | " [^ " ]* " |(?![ \' " ])[^> \ s]*))? ' )
HTMLParserTreeBuilder . attrfind_tolerant = attrfind_tolerant
locatestarttagend = re . compile ( r """
< [ a - zA - Z ] [ - . a - zA - Z0 - 9 : _ ] * # tag name
( ? : \s + # whitespace before attribute name
( ? : [ a - zA - Z_ ] [ - . : a - zA - Z0 - 9 _ ] * # attribute name
( ? : \s * = \s * # value indicator
( ? : ' [^ ' ] * ' # LITA-enclosed value
| \" [^ \" ]* \" # LIT-enclosed value
| [ ^ ' \" > \ s]+ # bare value
)
) ?
)
) *
\s * # trailing whitespace
""" , re.VERBOSE)
BeautifulSoupHTMLParser . locatestarttagend = locatestarttagend
from html . parser import tagfind , attrfind
def parse_starttag ( self , i ) :
self . __starttag_text = None
endpos = self . check_for_whole_start_tag ( i )
if endpos < 0 :
return endpos
rawdata = self . rawdata
self . __starttag_text = rawdata [ i : endpos ]
# Now parse the data between i+1 and j into a tag and attrs
attrs = [ ]
match = tagfind . match ( rawdata , i + 1 )
assert match , ' unexpected call to parse_starttag() '
k = match . end ( )
self . lasttag = tag = rawdata [ i + 1 : k ] . lower ( )
while k < endpos :
if self . strict :
m = attrfind . match ( rawdata , k )
else :
m = attrfind_tolerant . match ( rawdata , k )
if not m :
break
attrname , rest , attrvalue = m . group ( 1 , 2 , 3 )
if not rest :
attrvalue = None
elif attrvalue [ : 1 ] == ' \' ' == attrvalue [ - 1 : ] or \
attrvalue [ : 1 ] == ' " ' == attrvalue [ - 1 : ] :
attrvalue = attrvalue [ 1 : - 1 ]
if attrvalue :
attrvalue = self . unescape ( attrvalue )
attrs . append ( ( attrname . lower ( ) , attrvalue ) )
k = m . end ( )
end = rawdata [ k : endpos ] . strip ( )
if end not in ( " > " , " /> " ) :
lineno , offset = self . getpos ( )
if " \n " in self . __starttag_text :
lineno = lineno + self . __starttag_text . count ( " \n " )
offset = len ( self . __starttag_text ) \
- self . __starttag_text . rfind ( " \n " )
else :
offset = offset + len ( self . __starttag_text )
if self . strict :
self . error ( " junk characters in start tag: %r "
% ( rawdata [ k : endpos ] [ : 20 ] , ) )
self . handle_data ( rawdata [ i : endpos ] )
return endpos
if end . endswith ( ' /> ' ) :
# XHTML-style empty tag: <span attr="value" />
self . handle_startendtag ( tag , attrs )
else :
self . handle_starttag ( tag , attrs )
if tag in self . CDATA_CONTENT_ELEMENTS :
self . set_cdata_mode ( tag )
return endpos
def set_cdata_mode ( self , elem ) :
self . cdata_elem = elem . lower ( )
self . interesting = re . compile ( r ' </ \ s* %s \ s*> ' % self . cdata_elem , re . I )
BeautifulSoupHTMLParser . parse_starttag = parse_starttag
BeautifulSoupHTMLParser . set_cdata_mode = set_cdata_mode
CONSTRUCTOR_TAKES_STRICT = True