Source

n0v4pl4n3t / werkzeug / debug / tbtools.py

Full commit
  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
# -*- coding: utf-8 -*-
"""
    werkzeug.debug.tbtools
    ~~~~~~~~~~~~~~~~~~~~~~

    This module provides various traceback related utility functions.

    :copyright: (c) 2010 by the Werkzeug Team, see AUTHORS for more details.
    :license: BSD.
"""
import re
import os
import sys
import inspect
import traceback
import codecs
from tokenize import TokenError
from werkzeug.utils import cached_property, escape
from werkzeug.debug.console import Console

_coding_re = re.compile(r'coding[:=]\s*([-\w.]+)')
_line_re = re.compile(r'^(.*?)$(?m)')
_funcdef_re = re.compile(r'^(\s*def\s)|(.*(?<!\w)lambda(:|\s))|^(\s*@)')
UTF8_COOKIE = '\xef\xbb\xbf'

system_exceptions = (SystemExit, KeyboardInterrupt)
try:
    system_exceptions += (GeneratorExit,)
except NameError:
    pass


HEADER = u'''\
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
  "http://www.w3.org/TR/html4/loose.dtd">
<html>
  <head>
    <title>%(title)s // Werkzeug Debugger</title>
    <link rel="stylesheet" href="?__debugger__=yes&amp;cmd=resource&amp;f=style.css" type="text/css">
    <script type="text/javascript" src="?__debugger__=yes&amp;cmd=resource&amp;f=jquery.js"></script>
    <script type="text/javascript" src="?__debugger__=yes&amp;cmd=resource&amp;f=debugger.js"></script>
    <script type="text/javascript">
      var TRACEBACK = %(traceback_id)d,
          CONSOLE_MODE = %(console)s,
          EVALEX = %(evalex)s
    </script>
  </head>
  <body>
    <div class="debugger">
'''
FOOTER = u'''\
      <div class="footer">
        Brought to you by <strong class="arthur">DON'T PANIC</strong>, your
        friendly Werkzeug powered traceback interpreter.
      </div>
    </div>
  </body>
</html>
'''

PAGE_HTML = HEADER + u'''\
<h1>%(exception_type)s</h1>
<div class="detail">
  <p class="errormsg">%(exception)s</p>
</div>
<h2 class="traceback">Traceback <em>(most recent call last)</em></h2>
%(summary)s
<div class="plain">
  <form action="%(lodgeit_url)s" method="post">
    <p>
      <input type="hidden" name="language" value="pytb">
      This is the Copy/Paste friendly version of the traceback.  <span
      class="pastemessage">You can also paste this traceback into LodgeIt:
      <input type="submit" value="create paste"></span>
    </p>
    <textarea cols="50" rows="10" name="code" readonly>%(plaintext)s</textarea>
  </form>
</div>
<div class="explanation">
  The debugger caught an exception in your WSGI application.  You can now
  look at the traceback which led to the error.  <span class="nojavascript">
  If you enable JavaScript you can also use additional features such as code
  execution (if the evalex feature is enabled), automatic pasting of the
  exceptions and much more.</span>
</div>
''' + FOOTER + '''
<!--

%(plaintext_cs)s

-->
'''

CONSOLE_HTML = HEADER + u'''\
<h1>Interactive Console</h1>
<div class="explanation">
In this console you can execute Python expressions in the context of the
application.  The initial namespace was created by the debugger automatically.
</div>
<div class="console"><div class="inner">The Console requires JavaScript.</div></div>
''' + FOOTER

SUMMARY_HTML = u'''\
<div class="%(classes)s">
  %(title)s
  <ul>%(frames)s</ul>
  %(description)s
</div>
'''

FRAME_HTML = u'''\
<div class="frame" id="frame-%(id)d">
  <h4>File <cite class="filename">"%(filename)s"</cite>,
      line <em class="line">%(lineno)s</em>,
      in <code class="function">%(function_name)s</code></h4>
  <pre>%(current_line)s</pre>
</div>
'''

SOURCE_TABLE_HTML = u'<table class=source>%s</table>'

SOURCE_LINE_HTML = u'''\
<tr class="%(classes)s">
  <td class=lineno>%(lineno)s</td>
  <td>%(code)s</td>
</tr>
'''


def render_console_html():
    return CONSOLE_HTML % {
        'evalex':           'true',
        'console':          'true',
        'title':            'Console',
        'traceback_id':     -1
    }


def get_current_traceback(ignore_system_exceptions=False,
                          show_hidden_frames=False, skip=0):
    """Get the current exception info as `Traceback` object.  Per default
    calling this method will reraise system exceptions such as generator exit,
    system exit or others.  This behavior can be disabled by passing `False`
    to the function as first parameter.
    """
    exc_type, exc_value, tb = sys.exc_info()
    if ignore_system_exceptions and exc_type in system_exceptions:
        raise
    for x in xrange(skip):
        if tb.tb_next is None:
            break
        tb = tb.tb_next
    tb = Traceback(exc_type, exc_value, tb)
    if not show_hidden_frames:
        tb.filter_hidden_frames()
    return tb


class Line(object):
    """Helper for the source renderer."""
    __slots__ = ('lineno', 'code', 'in_frame', 'current')

    def __init__(self, lineno, code):
        self.lineno = lineno
        self.code = code
        self.in_frame = False
        self.current = False

    def classes(self):
        rv = ['line']
        if self.in_frame:
            rv.append('in-frame')
        if self.current:
            rv.append('current')
        return rv
    classes = property(classes)

    def render(self):
        return SOURCE_LINE_HTML % {
            'classes':      u' '.join(self.classes),
            'lineno':       self.lineno,
            'code':         escape(self.code)
        }


class Traceback(object):
    """Wraps a traceback."""

    def __init__(self, exc_type, exc_value, tb):
        self.exc_type = exc_type
        self.exc_value = exc_value
        if not isinstance(exc_type, str):
            exception_type = exc_type.__name__
            if exc_type.__module__ not in ('__builtin__', 'exceptions'):
                exception_type = exc_type.__module__ + '.' + exception_type
        else:
            exception_type = exc_type
        self.exception_type = exception_type

        # we only add frames to the list that are not hidden.  This follows
        # the the magic variables as defined by paste.exceptions.collector
        self.frames = []
        while tb:
            self.frames.append(Frame(exc_type, exc_value, tb))
            tb = tb.tb_next

    def filter_hidden_frames(self):
        """Remove the frames according to the paste spec."""
        if not self.frames:
            return

        new_frames = []
        hidden = False
        for frame in self.frames:
            hide = frame.hide
            if hide in ('before', 'before_and_this'):
                new_frames = []
                hidden = False
                if hide == 'before_and_this':
                    continue
            elif hide in ('reset', 'reset_and_this'):
                hidden = False
                if hide == 'reset_and_this':
                    continue
            elif hide in ('after', 'after_and_this'):
                hidden = True
                if hide == 'after_and_this':
                    continue
            elif hide or hidden:
                continue
            new_frames.append(frame)

        # if we only have one frame and that frame is from the codeop
        # module, remove it.
        if len(new_frames) == 1 and self.frames[0].module == 'codeop':
            del self.frames[:]

        # if the last frame is missing something went terrible wrong :(
        elif self.frames[-1] in new_frames:
            self.frames[:] = new_frames

    def is_syntax_error(self):
        """Is it a syntax error?"""
        return isinstance(self.exc_value, SyntaxError)
    is_syntax_error = property(is_syntax_error)

    def exception(self):
        """String representation of the exception."""
        buf = traceback.format_exception_only(self.exc_type, self.exc_value)
        return ''.join(buf).strip().decode('utf-8', 'replace')
    exception = property(exception)

    def log(self, logfile=None):
        """Log the ASCII traceback into a file object."""
        if logfile is None:
            logfile = sys.stderr
        tb = self.plaintext.encode('utf-8', 'replace').rstrip() + '\n'
        logfile.write(tb)

    def paste(self, lodgeit_url):
        """Create a paste and return the paste id."""
        from xmlrpclib import ServerProxy
        srv = ServerProxy('%sxmlrpc/' % lodgeit_url)
        return srv.pastes.newPaste('pytb', self.plaintext)

    def render_summary(self, include_title=True):
        """Render the traceback for the interactive console."""
        title = ''
        description = ''
        frames = []
        classes = ['traceback']
        if not self.frames:
            classes.append('noframe-traceback')

        if include_title:
            if self.is_syntax_error:
                title = u'Syntax Error'
            else:
                title = u'Traceback <em>(most recent call last)</em>:'

        for frame in self.frames:
            frames.append(u'<li%s>%s' % (
                frame.info and u' title="%s"' % escape(frame.info) or u'',
                frame.render()
            ))

        if self.is_syntax_error:
            description_wrapper = u'<pre class=syntaxerror>%s</pre>'
        else:
            description_wrapper = u'<blockquote>%s</blockquote>'

        return SUMMARY_HTML % {
            'classes':      u' '.join(classes),
            'title':        title and u'<h3>%s</h3>' % title or u'',
            'frames':       u'\n'.join(frames),
            'description':  description_wrapper % escape(self.exception)
        }

    def render_full(self, evalex=False, lodgeit_url=None):
        """Render the Full HTML page with the traceback info."""
        exc = escape(self.exception)
        return PAGE_HTML % {
            'evalex':           evalex and 'true' or 'false',
            'console':          'false',
            'lodgeit_url':      escape(lodgeit_url),
            'title':            exc,
            'exception':        exc,
            'exception_type':   escape(self.exception_type),
            'summary':          self.render_summary(include_title=False),
            'plaintext':        self.plaintext,
            'plaintext_cs':     re.sub('-{2,}', '-', self.plaintext),
            'traceback_id':     self.id
        }

    def generate_plaintext_traceback(self):
        """Like the plaintext attribute but returns a generator"""
        yield u'Traceback (most recent call last):'
        for frame in self.frames:
            yield u'  File "%s", line %s, in %s' % (
                frame.filename,
                frame.lineno,
                frame.function_name
            )
            yield u'    ' + frame.current_line.strip()
        yield self.exception

    def plaintext(self):
        return u'\n'.join(self.generate_plaintext_traceback())
    plaintext = cached_property(plaintext)

    id = property(lambda x: id(x))


class Frame(object):
    """A single frame in a traceback."""

    def __init__(self, exc_type, exc_value, tb):
        self.lineno = tb.tb_lineno
        self.function_name = tb.tb_frame.f_code.co_name
        self.locals = tb.tb_frame.f_locals
        self.globals = tb.tb_frame.f_globals

        fn = inspect.getsourcefile(tb) or inspect.getfile(tb)
        if fn[-4:] in ('.pyo', '.pyc'):
            fn = fn[:-1]
        # if it's a file on the file system resolve the real filename.
        if os.path.isfile(fn):
            fn = os.path.realpath(fn)
        self.filename = fn
        self.module = self.globals.get('__name__')
        self.loader = self.globals.get('__loader__')
        self.code = tb.tb_frame.f_code

        # support for paste's traceback extensions
        self.hide = self.locals.get('__traceback_hide__', False)
        info = self.locals.get('__traceback_info__')
        if info is not None:
            try:
                info = unicode(info)
            except UnicodeError:
                info = str(info).decode('utf-8', 'replace')
        self.info = info

    def render(self):
        """Render a single frame in a traceback."""
        return FRAME_HTML % {
            'id':               self.id,
            'filename':         escape(self.filename),
            'lineno':           self.lineno,
            'function_name':    escape(self.function_name),
            'current_line':     escape(self.current_line.strip())
        }

    def get_annotated_lines(self):
        """Helper function that returns lines with extra information."""
        lines = [Line(idx + 1, x) for idx, x in enumerate(self.sourcelines)]

        # find function definition and mark lines
        if hasattr(self.code, 'co_firstlineno'):
            lineno = self.code.co_firstlineno - 1
            while lineno > 0:
                if _funcdef_re.match(lines[lineno].code):
                    break
                lineno -= 1
            try:
                offset = len(inspect.getblock([x.code + '\n' for x
                                               in lines[lineno:]]))
            except TokenError:
                offset = 0
            for line in lines[lineno:lineno + offset]:
                line.in_frame = True

        # mark current line
        try:
            lines[self.lineno - 1].current = True
        except IndexError:
            pass

        return lines

    def render_source(self):
        """Render the sourcecode."""
        return SOURCE_TABLE_HTML % u'\n'.join(line.render() for line in
                                              self.get_annotated_lines())

    def eval(self, code, mode='single'):
        """Evaluate code in the context of the frame."""
        if isinstance(code, basestring):
            if isinstance(code, unicode):
                code = UTF8_COOKIE + code.encode('utf-8')
            code = compile(code, '<interactive>', mode)
        if mode != 'exec':
            return eval(code, self.globals, self.locals)
        exec code in self.globals, self.locals

    @cached_property
    def sourcelines(self):
        """The sourcecode of the file as list of unicode strings."""
        # get sourcecode from loader or file
        source = None
        if self.loader is not None:
            try:
                if hasattr(self.loader, 'get_source'):
                    source = self.loader.get_source(self.module)
                elif hasattr(self.loader, 'get_source_by_code'):
                    source = self.loader.get_source_by_code(self.code)
            except Exception:
                # we munch the exception so that we don't cause troubles
                # if the loader is broken.
                pass

        if source is None:
            try:
                f = file(self.filename)
            except IOError:
                return []
            try:
                source = f.read()
            finally:
                f.close()

        # already unicode?  return right away
        if isinstance(source, unicode):
            return source.splitlines()

        # yes. it should be ascii, but we don't want to reject too many
        # characters in the debugger if something breaks
        charset = 'utf-8'
        if source.startswith(UTF8_COOKIE):
            source = source[3:]
        else:
            for idx, match in enumerate(_line_re.finditer(source)):
                match = _line_re.search(match.group())
                if match is not None:
                    charset = match.group(1)
                    break
                if idx > 1:
                    break

        # on broken cookies we fall back to utf-8 too
        try:
            codecs.lookup(charset)
        except LookupError:
            charset = 'utf-8'

        return source.decode(charset, 'replace').splitlines()

    @property
    def current_line(self):
        try:
            return self.sourcelines[self.lineno - 1]
        except IndexError:
            return u''

    @cached_property
    def console(self):
        return Console(self.globals, self.locals)

    id = property(lambda x: id(x))