| author |
Steve Losh <steve@stevelosh.com> |
| date |
Fri, 11 Jun 2010 20:14:01 -0400 |
| parents |
(none) |
| children |
(none) |
# -*- 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
from werkzeug.debug.console import Console
from werkzeug.debug.utils import render_template
_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
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)
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."""
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 the last frame is missing something went terrible wrong :(
if 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):
"""Create a paste and return the paste id."""
from xmlrpclib import ServerProxy
srv = ServerProxy('http://paste.pocoo.org/xmlrpc/')
return srv.pastes.newPaste('pytb', self.plaintext)
def render_summary(self, include_title=True):
"""Render the traceback for the interactive console."""
return render_template('traceback_summary.html', traceback=self,
include_title=include_title)
def render_full(self, evalex=False):
"""Render the Full HTML page with the traceback info."""
return render_template('traceback_full.html', traceback=self,
evalex=evalex)
def plaintext(self):
return render_template('traceback_plaintext.html', traceback=self)
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 render_template('frame.html', frame=self)
def render_source(self):
"""Render the sourcecode."""
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 render_template('source.html', frame=self, lines=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:
# 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))