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"""HTML 2.0 parser.
See the HTML 2.0 specification:
http://www.w3.org/hypertext/WWW/MarkUp/html-spec/html-spec_toc.html
"""
import sgmllib
from formatter import AS_IS
__all__ = ["HTMLParser", "HTMLParseError"]
class HTMLParseError(sgmllib.SGMLParseError):
"""Error raised when an HTML document can't be parsed."""
class HTMLParser(sgmllib.SGMLParser):
"""This is the basic HTML parser class.
It supports all entity names required by the XHTML 1.0 Recommendation.
It also defines handlers for all HTML 2.0 and many HTML 3.0 and 3.2
elements.
"""
from htmlentitydefs import entitydefs
def __init__(self, formatter, verbose=0):
"""Creates an instance of the HTMLParser class.
The formatter parameter is the formatter instance associated with
the parser.
"""
sgmllib.SGMLParser.__init__(self, verbose)
self.formatter = formatter
def error(self, message):
raise HTMLParseError(message)
def reset(self):
sgmllib.SGMLParser.reset(self)
self.savedata = None
self.isindex = 0
self.title = None
self.base = None
self.anchor = None
self.anchorlist = []
self.nofill = 0
self.list_stack = []
# ------ Methods used internally; some may be overridden
# --- Formatter interface, taking care of 'savedata' mode;
# shouldn't need to be overridden
def handle_data(self, data):
if self.savedata is not None:
self.savedata = self.savedata + data
else:
if self.nofill:
self.formatter.add_literal_data(data)
else:
self.formatter.add_flowing_data(data)
# --- Hooks to save data; shouldn't need to be overridden
def save_bgn(self):
"""Begins saving character data in a buffer instead of sending it
to the formatter object.
Retrieve the stored data via the save_end() method. Use of the
save_bgn() / save_end() pair may not be nested.
"""
self.savedata = ''
def save_end(self):
"""Ends buffering character data and returns all data saved since
the preceding call to the save_bgn() method.
If the nofill flag is false, whitespace is collapsed to single
spaces. A call to this method without a preceding call to the
save_bgn() method will raise a TypeError exception.
"""
data = self.savedata
self.savedata = None
if not self.nofill:
data = ' '.join(data.split())
return data
# --- Hooks for anchors; should probably be overridden
def anchor_bgn(self, href, name, type):
"""This method is called at the start of an anchor region.
The arguments correspond to the attributes of the <A> tag with
the same names. The default implementation maintains a list of
hyperlinks (defined by the HREF attribute for <A> tags) within
the document. The list of hyperlinks is available as the data
attribute anchorlist.
"""
self.anchor = href
if self.anchor:
self.anchorlist.append(href)
def anchor_end(self):
"""This method is called at the end of an anchor region.
The default implementation adds a textual footnote marker using an
index into the list of hyperlinks created by the anchor_bgn()method.
"""
if self.anchor:
self.handle_data("[%d]" % len(self.anchorlist))
self.anchor = None
# --- Hook for images; should probably be overridden
def handle_image(self, src, alt, *args):
"""This method is called to handle images.
The default implementation simply passes the alt value to the
handle_data() method.
"""
self.handle_data(alt)
# --------- Top level elememts
def start_html(self, attrs): pass
def end_html(self): pass
def start_head(self, attrs): pass
def end_head(self): pass
def start_body(self, attrs): pass
def end_body(self): pass
# ------ Head elements
def start_title(self, attrs):
self.save_bgn()
def end_title(self):
self.title = self.save_end()
def do_base(self, attrs):
for a, v in attrs:
if a == 'href':
self.base = v
def do_isindex(self, attrs):
self.isindex = 1
def do_link(self, attrs):
pass
def do_meta(self, attrs):
pass
def do_nextid(self, attrs): # Deprecated
pass
# ------ Body elements
# --- Headings
def start_h1(self, attrs):
self.formatter.end_paragraph(1)
self.formatter.push_font(('h1', 0, 1, 0))
def end_h1(self):
self.formatter.end_paragraph(1)
self.formatter.pop_font()
def start_h2(self, attrs):
self.formatter.end_paragraph(1)
self.formatter.push_font(('h2', 0, 1, 0))
def end_h2(self):
self.formatter.end_paragraph(1)
self.formatter.pop_font()
def start_h3(self, attrs):
self.formatter.end_paragraph(1)
self.formatter.push_font(('h3', 0, 1, 0))
def end_h3(self):
self.formatter.end_paragraph(1)
self.formatter.pop_font()
def start_h4(self, attrs):
self.formatter.end_paragraph(1)
self.formatter.push_font(('h4', 0, 1, 0))
def end_h4(self):
self.formatter.end_paragraph(1)
self.formatter.pop_font()
def start_h5(self, attrs):
self.formatter.end_paragraph(1)
self.formatter.push_font(('h5', 0, 1, 0))
def end_h5(self):
self.formatter.end_paragraph(1)
self.formatter.pop_font()
def start_h6(self, attrs):
self.formatter.end_paragraph(1)
self.formatter.push_font(('h6', 0, 1, 0))
def end_h6(self):
self.formatter.end_paragraph(1)
self.formatter.pop_font()
# --- Block Structuring Elements
def do_p(self, attrs):
self.formatter.end_paragraph(1)
def start_pre(self, attrs):
self.formatter.end_paragraph(1)
self.formatter.push_font((AS_IS, AS_IS, AS_IS, 1))
self.nofill = self.nofill + 1
def end_pre(self):
self.formatter.end_paragraph(1)
self.formatter.pop_font()
self.nofill = max(0, self.nofill - 1)
def start_xmp(self, attrs):
self.start_pre(attrs)
self.setliteral('xmp') # Tell SGML parser
def end_xmp(self):
self.end_pre()
def start_listing(self, attrs):
self.start_pre(attrs)
self.setliteral('listing') # Tell SGML parser
def end_listing(self):
self.end_pre()
def start_address(self, attrs):
self.formatter.end_paragraph(0)
self.formatter.push_font((AS_IS, 1, AS_IS, AS_IS))
def end_address(self):
self.formatter.end_paragraph(0)
self.formatter.pop_font()
def start_blockquote(self, attrs):
self.formatter.end_paragraph(1)
self.formatter.push_margin('blockquote')
def end_blockquote(self):
self.formatter.end_paragraph(1)
self.formatter.pop_margin()
# --- List Elements
def start_ul(self, attrs):
self.formatter.end_paragraph(not self.list_stack)
self.formatter.push_margin('ul')
self.list_stack.append(['ul', '*', 0])
def end_ul(self):
if self.list_stack: del self.list_stack[-1]
self.formatter.end_paragraph(not self.list_stack)
self.formatter.pop_margin()
def do_li(self, attrs):
self.formatter.end_paragraph(0)
if self.list_stack:
[dummy, label, counter] = top = self.list_stack[-1]
top[2] = counter = counter+1
else:
label, counter = '*', 0
self.formatter.add_label_data(label, counter)
def start_ol(self, attrs):
self.formatter.end_paragraph(not self.list_stack)
self.formatter.push_margin('ol')
label = '1.'
for a, v in attrs:
if a == 'type':
if len(v) == 1: v = v + '.'
label = v
self.list_stack.append(['ol', label, 0])
def end_ol(self):
if self.list_stack: del self.list_stack[-1]
self.formatter.end_paragraph(not self.list_stack)
self.formatter.pop_margin()
def start_menu(self, attrs):
self.start_ul(attrs)
def end_menu(self):
self.end_ul()
def start_dir(self, attrs):
self.start_ul(attrs)
def end_dir(self):
self.end_ul()
def start_dl(self, attrs):
self.formatter.end_paragraph(1)
self.list_stack.append(['dl', '', 0])
def end_dl(self):
self.ddpop(1)
if self.list_stack: del self.list_stack[-1]
def do_dt(self, attrs):
self.ddpop()
def do_dd(self, attrs):
self.ddpop()
self.formatter.push_margin('dd')
self.list_stack.append(['dd', '', 0])
def ddpop(self, bl=0):
self.formatter.end_paragraph(bl)
if self.list_stack:
if self.list_stack[-1][0] == 'dd':
del self.list_stack[-1]
self.formatter.pop_margin()
# --- Phrase Markup
# Idiomatic Elements
def start_cite(self, attrs): self.start_i(attrs)
def end_cite(self): self.end_i()
def start_code(self, attrs): self.start_tt(attrs)
def end_code(self): self.end_tt()
def start_em(self, attrs): self.start_i(attrs)
def end_em(self): self.end_i()
def start_kbd(self, attrs): self.start_tt(attrs)
def end_kbd(self): self.end_tt()
def start_samp(self, attrs): self.start_tt(attrs)
def end_samp(self): self.end_tt()
def start_strong(self, attrs): self.start_b(attrs)
def end_strong(self): self.end_b()
def start_var(self, attrs): self.start_i(attrs)
def end_var(self): self.end_i()
# Typographic Elements
def start_i(self, attrs):
self.formatter.push_font((AS_IS, 1, AS_IS, AS_IS))
def end_i(self):
self.formatter.pop_font()
def start_b(self, attrs):
self.formatter.push_font((AS_IS, AS_IS, 1, AS_IS))
def end_b(self):
self.formatter.pop_font()
def start_tt(self, attrs):
self.formatter.push_font((AS_IS, AS_IS, AS_IS, 1))
def end_tt(self):
self.formatter.pop_font()
def start_a(self, attrs):
href = ''
name = ''
type = ''
for attrname, value in attrs:
value = value.strip()
if attrname == 'href':
href = value
if attrname == 'name':
name = value
if attrname == 'type':
type = value.lower()
self.anchor_bgn(href, name, type)
def end_a(self):
self.anchor_end()
# --- Line Break
def do_br(self, attrs):
self.formatter.add_line_break()
# --- Horizontal Rule
def do_hr(self, attrs):
self.formatter.add_hor_rule()
# --- Image
def do_img(self, attrs):
align = ''
alt = '(image)'
ismap = ''
src = ''
width = 0
height = 0
for attrname, value in attrs:
if attrname == 'align':
align = value
if attrname == 'alt':
alt = value
if attrname == 'ismap':
ismap = value
if attrname == 'src':
src = value
if attrname == 'width':
try: width = int(value)
except ValueError: pass
if attrname == 'height':
try: height = int(value)
except ValueError: pass
self.handle_image(src, alt, ismap, align, width, height)
# --- Really Old Unofficial Deprecated Stuff
def do_plaintext(self, attrs):
self.start_pre(attrs)
self.setnomoretags() # Tell SGML parser
# --- Unhandled tags
def unknown_starttag(self, tag, attrs):
pass
def unknown_endtag(self, tag):
pass
def test(args = None):
import sys, formatter
if not args:
args = sys.argv[1:]
silent = args and args[0] == '-s'
if silent:
del args[0]
if args:
file = args[0]
else:
file = 'test.html'
if file == '-':
f = sys.stdin
else:
try:
f = open(file, 'r')
except IOError, msg:
print file, ":", msg
sys.exit(1)
data = f.read()
if f is not sys.stdin:
f.close()
if silent:
f = formatter.NullFormatter()
else:
f = formatter.AbstractFormatter(formatter.DumbWriter())
p = HTMLParser(f)
p.feed(data)
p.close()
if __name__ == '__main__':
test()
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