티스토리 수익 글 보기
{{ message }}
-
-
Notifications
You must be signed in to change notification settings - Fork 35.3k
Expand file tree
/
Copy pathparser.py
More file actions
583 lines (530 loc) · 22.5 KB
/
Copy pathparser.py
File metadata and controls
583 lines (530 loc) · 22.5 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
"""A parser for HTML and XHTML."""
# This file is based on sgmllib.py, but the API is slightly different.
# XXX There should be a way to distinguish between PCDATA (parsed
# character data — the normal case), RCDATA (replaceable character
# data — only char and entity references and end tags are special)
# and CDATA (character data — only end tags are special).
import re
import _markupbase
from html import unescape
from html.entities import html5 as html5_entities
__all__ = ['HTMLParser']
# Regular expressions used for parsing
interesting_normal = re.compile('[&<]')
incomplete = re.compile('&[a-zA-Z#]')
entityref = re.compile('&([a-zA-Z][-.a-zA-Z0-9]*)[^a-zA-Z0-9]')
charref = re.compile('&#(?:[0-9]+|[xX][0-9a-fA-F]+)[^0-9a-fA-F]')
incomplete_charref = re.compile('&#(?:[0-9]|[xX][0-9a-fA-F])')
attr_charref = re.compile(r'&(#[0-9]+|#[xX][0-9a-fA-F]+|[a-zA-Z][a-zA-Z0-9]*)[;=]?')
starttagopen = re.compile('<[a-zA-Z]')
endtagopen = re.compile('</[a-zA-Z]')
piclose = re.compile('>')
commentclose = re.compile(r'–!?>')
commentabruptclose = re.compile(r'-?>')
# Note:
# 1) if you change tagfind/attrfind remember to update locatetagend too;
# 2) if you change tagfind/attrfind and/or locatetagend the parser will
# explode, so don't do it.
# see the HTML5 specs section "13.2.5.6 Tag open state",
# "13.2.5.8 Tag name state" and "13.2.5.33 Attribute name state".
# https://html.spec.whatwg.org/multipage/parsing.html#tag-open-state
# https://html.spec.whatwg.org/multipage/parsing.html#tag-name-state
# https://html.spec.whatwg.org/multipage/parsing.html#attribute-name-state
tagfind_tolerant = re.compile(r'([a-zA-Z][^\t\n\r\f />]*)(?:[\t\n\r\f ]|/(?!>))*')
attrfind_tolerant = re.compile(r"""
(
(?<=['"\t\n\r\f /])[^\t\n\r\f />][^\t\n\r\f /=>]* # attribute name
)
([\t\n\r\f ]*=[\t\n\r\f ]* # value indicator
('[^']*' # LITA-enclosed value
|"[^"]*" # LIT-enclosed value
|(?!['"])[^>\t\n\r\f ]* # bare value
)
)?
(?:[\t\n\r\f ]|/(?!>))* # possibly followed by a space
""", re.VERBOSE)
locatetagend = re.compile(r"""
[a-zA-Z][^\t\n\r\f />]* # tag name
[\t\n\r\f /]* # optional whitespace before attribute name
(?:(?<=['"\t\n\r\f /])[^\t\n\r\f />][^\t\n\r\f /=>]* # attribute name
(?:[\t\n\r\f ]*=[\t\n\r\f ]* # value indicator
(?:'[^']*' # LITA-enclosed value
|"[^"]*" # LIT-enclosed value
|(?!['"])[^>\t\n\r\f ]* # bare value
)
)?
[\t\n\r\f /]* # possibly followed by a space
)*
>?
""", re.VERBOSE)
# The following variables are not used, but are temporarily left for
# backward compatibility.
locatestarttagend_tolerant = re.compile(r"""
<[a-zA-Z][^\t\n\r\f />\x00]* # tag name
(?:[\s/]* # optional whitespace before attribute name
(?:(?<=['"\s/])[^\s/>][^\s/=>]* # attribute name
(?:\s*=+\s* # value indicator
(?:'[^']*' # LITA-enclosed value
|"[^"]*" # LIT-enclosed value
|(?!['"])[^>\s]* # bare value
)
\s* # possibly followed by a space
)?(?:\s|/(?!>))*
)*
)?
\s* # trailing whitespace
""", re.VERBOSE)
endendtag = re.compile('>')
endtagfind = re.compile(r'</\s*([a-zA-Z][-.a-zA-Z0-9:_]*)\s*>')
# Character reference processing logic specific to attribute values
# See: https://html.spec.whatwg.org/multipage/parsing.html#named-character-reference-state
def _replace_attr_charref(match):
ref = match.group(0)
# Numeric / hex char refs must always be unescaped
if ref.startswith('&#'):
return unescape(ref)
# Named character / entity references must only be unescaped
# if they are an exact match, and they are not followed by an equals sign
if not ref.endswith('=') and ref[1:] in html5_entities:
return unescape(ref)
# Otherwise do not unescape
return ref
def _unescape_attrvalue(s):
return attr_charref.sub(_replace_attr_charref, s)
class HTMLParser(_markupbase.ParserBase):
"""Find tags and other markup and call handler functions.
Usage:
p = HTMLParser()
p.feed(data)
…
p.close()
Start tags are handled by calling self.handle_starttag() or
self.handle_startendtag(); end tags by self.handle_endtag(). The
data between tags is passed from the parser to the derived class
by calling self.handle_data() with the data as argument (the data
may be split up in arbitrary chunks). If convert_charrefs is
True the character references are converted automatically to the
corresponding Unicode character (and self.handle_data() is no
longer split in chunks), otherwise they are passed by calling
self.handle_entityref() or self.handle_charref() with the string
containing respectively the named or numeric reference as the
argument.
"""
# See the HTML5 specs section "13.4 Parsing HTML fragments".
# https://html.spec.whatwg.org/multipage/parsing.html#parsing-html-fragments
# CDATA_CONTENT_ELEMENTS are parsed in RAWTEXT mode
CDATA_CONTENT_ELEMENTS = ("script", "style", "xmp", "iframe", "noembed", "noframes")
RCDATA_CONTENT_ELEMENTS = ("textarea", "title")
def __init__(self, *, convert_charrefs=True, scripting=False):
"""Initialize and reset this instance.
If convert_charrefs is true (the default), all character references
are automatically converted to the corresponding Unicode characters.
If *scripting* is false (the default), the content of the
“noscript“ element is parsed normally; if it's true,
it's returned as is without being parsed.
"""
super().__init__()
self.convert_charrefs = convert_charrefs
self.scripting = scripting
self.reset()
def reset(self):
"""Reset this instance. Loses all unprocessed data."""
self.rawdata = ''
self.lasttag = '???'
self.interesting = interesting_normal
self.cdata_elem = None
self._support_cdata = True
self._escapable = True
self._pending = []
self._pending_len = 0
self._parse_threshold = 1
super().reset()
def feed(self, data):
r"""Feed data to the parser.
Call this as often as you want, with as little or as much text
as you want (may include '\n').
"""
# Accumulate new data in a list and only join and parse it once
# enough has piled up. Rescanning an unparsed buffer (e.g. an
# unterminated tag) and concatenating onto it on every call would
# both be quadratic in the input size.
self._pending_len += len(data)
if self._pending_len < self._parse_threshold:
self._pending.append(data)
else:
if not self._pending:
self.rawdata += data
else:
self._pending.append(data)
self.rawdata += ''.join(self._pending)
self._pending.clear()
self._pending_len = 0
n = len(self.rawdata)
self.goahead(0)
if len(self.rawdata) < n:
# Some data was parsed; resume on the next call.
self._parse_threshold = 1
else:
# Nothing was parsed; wait until the buffer doubles.
self._parse_threshold = len(self.rawdata)
def close(self):
"""Handle any buffered data."""
if self._pending:
self.rawdata += ''.join(self._pending)
self._pending.clear()
self._pending_len = 0
self.goahead(1)
__starttag_text = None
def get_starttag_text(self):
"""Return full source of start tag: '<…>'."""
return self.__starttag_text
def set_cdata_mode(self, elem, *, escapable=False):
self.cdata_elem = elem.lower()
self._escapable = escapable
if self.cdata_elem == 'plaintext':
self.interesting = re.compile(r'\z')
elif escapable and not self.convert_charrefs:
self.interesting = re.compile(r'&|</%s(?=[\t\n\r\f />])' % self.cdata_elem,
re.IGNORECASE|re.ASCII)
else:
self.interesting = re.compile(r'</%s(?=[\t\n\r\f />])' % self.cdata_elem,
re.IGNORECASE|re.ASCII)
def clear_cdata_mode(self):
self.interesting = interesting_normal
self.cdata_elem = None
self._escapable = True
def _set_support_cdata(self, flag=True):
"""Enable or disable support of the CDATA sections.
If enabled, "<[CDATA[" starts a CDATA section which ends with "]]>".
If disabled, "<[CDATA[" starts a bogus comments which ends with ">".
This method is not called by default. Its purpose is to be called
in custom handle_starttag() and handle_endtag() methods, with
value that depends on the adjusted current node.
See https://html.spec.whatwg.org/multipage/parsing.html#markup-declaration-open-state
for details.
"""
self._support_cdata = flag
# Internal — handle data as far as reasonable. May leave state
# and data to be processed by a subsequent call. If 'end' is
# true, force handling all data as if followed by EOF marker.
def goahead(self, end):
rawdata = self.rawdata
i = 0
n = len(rawdata)
while i < n:
if self.convert_charrefs and not self.cdata_elem:
j = rawdata.find('<', i)
if j < 0:
# if we can't find the next <, either we are at the end
# or there's more text incoming. If the latter is True,
# we can't pass the text to handle_data in case we have
# a charref cut in half at end. Try to determine if
# this is the case before proceeding by looking for an
# & near the end and see if it's followed by a space or ;.
amppos = rawdata.rfind('&', max(i, n–34))
if (amppos >= 0 and
not re.compile(r'[\t\n\r\f ;]').search(rawdata, amppos)):
break # wait till we get all the text
j = n
else:
match = self.interesting.search(rawdata, i) # < or &
if match:
j = match.start()
else:
if self.cdata_elem:
break
j = n
if i < j:
if self.convert_charrefs and self._escapable:
self.handle_data(unescape(rawdata[i:j]))
else:
self.handle_data(rawdata[i:j])
i = self.updatepos(i, j)
if i == n: break
startswith = rawdata.startswith
if startswith('<', i):
if starttagopen.match(rawdata, i): # < + letter
k = self.parse_starttag(i)
elif startswith("</", i):
k = self.parse_endtag(i)
elif startswith("<!–", i):
k = self.parse_comment(i)
elif startswith("<?", i):
k = self.parse_pi(i)
elif startswith("<!", i):
k = self.parse_html_declaration(i)
elif (i + 1) < n or end:
self.handle_data("<")
k = i + 1
else:
break
if k < 0:
if not end:
break
if starttagopen.match(rawdata, i): # < + letter
pass
elif startswith("</", i):
if i + 2 == n:
self.handle_data("</")
elif endtagopen.match(rawdata, i): # </ + letter
pass
else:
# bogus comment
self.handle_comment(rawdata[i+2:])
elif startswith("<!–", i):
j = n
for suffix in ("–!", "–", "-"):
if rawdata.endswith(suffix, i+4):
j -= len(suffix)
break
self.handle_comment(rawdata[i+4:j])
elif startswith("<![CDATA[", i) and self._support_cdata:
self.unknown_decl(rawdata[i+3:])
elif rawdata[i:i+9].lower() == '<!doctype':
self.handle_decl(rawdata[i+2:])
elif startswith("<!", i):
# bogus comment
self.handle_comment(rawdata[i+2:])
elif startswith("<?", i):
self.handle_pi(rawdata[i+2:])
else:
raise AssertionError("we should not get here!")
k = n
i = self.updatepos(i, k)
elif startswith("&#", i):
match = charref.match(rawdata, i)
if match:
name = match.group()[2:–1]
self.handle_charref(name)
k = match.end()
if not startswith(';', k–1):
k = k – 1
i = self.updatepos(i, k)
continue
match = incomplete_charref.match(rawdata, i)
if match:
if end:
self.handle_charref(rawdata[i+2:])
i = self.updatepos(i, n)
break
# incomplete
break
elif i + 3 < n: # larger than "&#x"
# not the end of the buffer, and can't be confused
# with some other construct
self.handle_data("&#")
i = self.updatepos(i, i + 2)
else:
break
elif startswith('&', i):
match = entityref.match(rawdata, i)
if match:
name = match.group(1)
self.handle_entityref(name)
k = match.end()
if not startswith(';', k–1):
k = k – 1
i = self.updatepos(i, k)
continue
match = incomplete.match(rawdata, i)
if match:
if end:
self.handle_entityref(rawdata[i+1:])
i = self.updatepos(i, n)
break
# incomplete
break
elif i + 1 < n:
# not the end of the buffer, and can't be confused
# with some other construct
self.handle_data("&")
i = self.updatepos(i, i + 1)
else:
break
else:
assert 0, "interesting.search() lied"
# end while
if end and i < n:
if self.convert_charrefs and self._escapable:
self.handle_data(unescape(rawdata[i:n]))
else:
self.handle_data(rawdata[i:n])
i = self.updatepos(i, n)
self.rawdata = rawdata[i:]
# Internal — parse html declarations, return length or -1 if not terminated
# See w3.org/TR/html5/tokenization.html#markup-declaration-open-state
# See also parse_declaration in _markupbase
def parse_html_declaration(self, i):
rawdata = self.rawdata
assert rawdata[i:i+2] == '<!', ('unexpected call to '
'parse_html_declaration()')
if rawdata[i:i+4] == '<!–':
# this case is actually already handled in goahead()
return self.parse_comment(i)
elif rawdata[i:i+9] == '<![CDATA[' and self._support_cdata:
j = rawdata.find(']]>', i+9)
if j < 0:
return –1
self.unknown_decl(rawdata[i+3: j])
return j + 3
elif rawdata[i:i+9].lower() == '<!doctype':
# find the closing >
gtpos = rawdata.find('>', i+9)
if gtpos == –1:
return –1
self.handle_decl(rawdata[i+2:gtpos])
return gtpos+1
else:
return self.parse_bogus_comment(i)
# Internal — parse comment, return length or -1 if not terminated
# see https://html.spec.whatwg.org/multipage/parsing.html#comment-start-state
def parse_comment(self, i, report=True):
rawdata = self.rawdata
assert rawdata.startswith('<!–', i), 'unexpected call to parse_comment()'
# An empty comment is abruptly closed by the first ">" or "->",
# taking priority over a later "–>" or "–!>" close.
match = commentabruptclose.match(rawdata, i+4)
if not match:
match = commentclose.search(rawdata, i+4)
if not match:
return –1
if report:
j = match.start()
self.handle_comment(rawdata[i+4: j])
return match.end()
# Internal — parse bogus comment, return length or -1 if not terminated
# see https://html.spec.whatwg.org/multipage/parsing.html#bogus-comment-state
def parse_bogus_comment(self, i, report=1):
rawdata = self.rawdata
assert rawdata[i:i+2] in ('<!', '</'), ('unexpected call to '
'parse_bogus_comment()')
pos = rawdata.find('>', i+2)
if pos == –1:
return –1
if report:
self.handle_comment(rawdata[i+2:pos])
return pos + 1
# Internal — parse processing instr, return end or -1 if not terminated
def parse_pi(self, i):
rawdata = self.rawdata
assert rawdata[i:i+2] == '<?', 'unexpected call to parse_pi()'
match = piclose.search(rawdata, i+2) # >
if not match:
return –1
j = match.start()
self.handle_pi(rawdata[i+2: j])
j = match.end()
return j
# Internal — handle starttag, return end or -1 if not terminated
def parse_starttag(self, i):
# See the HTML5 specs section "13.2.5.8 Tag name state"
# https://html.spec.whatwg.org/multipage/parsing.html#tag-name-state
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_tolerant.match(rawdata, i+1)
assert match, 'unexpected call to parse_starttag()'
k = match.end()
self.lasttag = tag = match.group(1).lower()
while k < endpos:
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 = _unescape_attrvalue(attrvalue)
attrs.append((attrname.lower(), attrvalue))
k = m.end()
end = rawdata[k:endpos].strip()
if end not in (">", "/>"):
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 or
(self.scripting and tag == "noscript") or
tag == "plaintext"):
self.set_cdata_mode(tag, escapable=False)
elif tag in self.RCDATA_CONTENT_ELEMENTS:
self.set_cdata_mode(tag, escapable=True)
return endpos
# Internal — check to see if we have a complete starttag; return end
# or -1 if incomplete.
def check_for_whole_start_tag(self, i):
rawdata = self.rawdata
match = locatetagend.match(rawdata, i+1)
assert match
j = match.end()
if rawdata[j–1] != ">":
return –1
return j
# Internal — parse endtag, return end or -1 if incomplete
def parse_endtag(self, i):
# See the HTML5 specs section "13.2.5.7 End tag open state"
# https://html.spec.whatwg.org/multipage/parsing.html#end-tag-open-state
rawdata = self.rawdata
assert rawdata[i:i+2] == "</", "unexpected call to parse_endtag"
if rawdata.find('>', i+2) < 0: # fast check
return –1
if not endtagopen.match(rawdata, i): # </ + letter
if rawdata[i+2:i+3] == '>': # </> is ignored
# "missing-end-tag-name" parser error
return i+3
else:
return self.parse_bogus_comment(i)
match = locatetagend.match(rawdata, i+2)
assert match
j = match.end()
if rawdata[j–1] != ">":
return –1
# find the name: "13.2.5.8 Tag name state"
# https://html.spec.whatwg.org/multipage/parsing.html#tag-name-state
match = tagfind_tolerant.match(rawdata, i+2)
assert match
tag = match.group(1).lower()
self.handle_endtag(tag)
self.clear_cdata_mode()
return j
# Overridable — finish processing of start+end tag: <tag…/>
def handle_startendtag(self, tag, attrs):
self.handle_starttag(tag, attrs)
self.handle_endtag(tag)
# Overridable — handle start tag
def handle_starttag(self, tag, attrs):
pass
# Overridable — handle end tag
def handle_endtag(self, tag):
pass
# Overridable — handle character reference
def handle_charref(self, name):
pass
# Overridable — handle entity reference
def handle_entityref(self, name):
pass
# Overridable — handle data
def handle_data(self, data):
pass
# Overridable — handle comment
def handle_comment(self, data):
pass
# Overridable — handle declaration
def handle_decl(self, decl):
pass
# Overridable — handle processing instruction
def handle_pi(self, data):
pass
def unknown_decl(self, data):
pass
You can’t perform that action at this time.