# -*- coding: utf-8 -*-
"""
werkzeug.debug.tbtools
~~~~~~~~~~~~~~~~~~~~~~
This module provides various traceback related utility functions.
:copyright: (c) 2013 by the Werkzeug Team, see AUTHORS for more details.
:license: BSD.
"""
import re
import os
import sys
import json
import inspect
import traceback
import codecs
from tokenize import TokenError
from werkzeug.utils import cached_property, escape
from werkzeug.debug.console import Console
from werkzeug._compat import range_type, PY2, text_type, string_types
_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&cmd=resource&f=style.css" type="text/css">
<!-- We need to make sure this has a favicon so that the debugger does not by
accident trigger a request to /favicon.ico which might change the application
state. -->
<link rel="shortcut icon" href="?__debugger__=yes&cmd=resource&f=console.png">
<script type="text/javascript" src="?__debugger__=yes&cmd=resource&f=jquery.js"></script>
<script type="text/javascript" src="?__debugger__=yes&cmd=resource&f=debugger.js"></script>
<script type="text/javascript">
var TRACEBACK = %(traceback_id)d,
CONSOLE_MODE = %(console)s,
EVALEX = %(evalex)s,
SECRET = "%(secret)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="/?__debugger__=yes&cmd=paste" 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
a <a href="https://gist.github.com/">gist</a>:
<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(secret):
return CONSOLE_HTML % {
'evalex': 'true',
'console': 'true',
'title': 'Console',
'secret': secret,
'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 range_type(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)
rv = ''.join(buf).strip()
return rv.decode('utf-8', 'replace') if PY2 else rv
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.rstrip() + u'\n'
if PY2:
tb.encode('utf-8', 'replace')
logfile.write(tb)
def paste(self):
"""Create a paste and return the paste id."""
data = json.dumps({
'description': 'Werkzeug Internal Server Error',
'public': False,
'files': {
'traceback.txt': {
'content': self.plaintext
}
}
}).encode('utf-8')
try:
from urllib2 import urlopen
except ImportError:
from urllib.request import urlopen
rv = urlopen('https://api.github.com/gists', data=data)
resp = json.loads(rv.read().decode('utf-8'))
rv.close()
return {
'url': resp['html_url'],
'id': resp['id']
}
def render_summary(self, include_title=True):
"""Render the traceback for the interactive console."""
title = ''
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, secret=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',
'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,
'secret': secret
}
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 = text_type(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, string_types):
if PY2 and isinstance(code, unicode):
code = UTF8_COOKIE + code.encode('utf-8')
code = compile(code, '<interactive>', mode)
return eval(code, 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 = open(self.filename)
except IOError:
return []
try:
source = f.read()
finally:
f.close()
# already unicode? return right away
if isinstance(source, text_type):
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))
