cpython/Lib/cgitb.py

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"""More comprehensive traceback formatting for Python scripts.
To enable this module, do:
import cgitb; cgitb.enable()
at the top of your script. The optional arguments to enable() are:
display - if true, tracebacks are displayed in the web browser
logdir - if set, tracebacks are written to files in this directory
context - number of lines of source code to show for each stack frame
2003-06-29 02:46:54 -03:00
format - 'text' or 'html' controls the output format
By default, tracebacks are displayed but not saved, the context is 5 lines
and the output format is 'html' (for backwards compatibility with the
original use of this module)
Alternatively, if you have caught an exception and want cgitb to display it
for you, call cgitb.handler(). The optional argument to handler() is a
3-item tuple (etype, evalue, etb) just like the value of sys.exc_info().
The default handler displays output as HTML.
"""
__author__ = 'Ka-Ping Yee'
__version__ = '$Revision$'
import sys
def reset():
"""Return a string that resets the CGI and browser to a known state."""
return '''<!--: spam
Content-Type: text/html
<body bgcolor="#f0f0f8"><font color="#f0f0f8" size="-5"> -->
<body bgcolor="#f0f0f8"><font color="#f0f0f8" size="-5"> --> -->
</font> </font> </font> </script> </object> </blockquote> </pre>
</table> </table> </table> </table> </table> </font> </font> </font>'''
__UNDEF__ = [] # a special sentinel object
def small(text):
if text:
return '<small>' + text + '</small>'
else:
return ''
def strong(text):
if text:
return '<strong>' + text + '</strong>'
else:
return ''
def grey(text):
if text:
return '<font color="#909090">' + text + '</font>'
else:
return ''
def lookup(name, frame, locals):
"""Find the value for a given name in the given environment."""
if name in locals:
return 'local', locals[name]
if name in frame.f_globals:
return 'global', frame.f_globals[name]
if '__builtins__' in frame.f_globals:
builtins = frame.f_globals['__builtins__']
if type(builtins) is type({}):
if name in builtins:
return 'builtin', builtins[name]
else:
if hasattr(builtins, name):
return 'builtin', getattr(builtins, name)
return None, __UNDEF__
def scanvars(reader, frame, locals):
"""Scan one logical line of Python and look up values of variables used."""
import tokenize, keyword
vars, lasttoken, parent, prefix, value = [], None, None, '', __UNDEF__
for ttype, token, start, end, line in tokenize.generate_tokens(reader):
if ttype == tokenize.NEWLINE: break
if ttype == tokenize.NAME and token not in keyword.kwlist:
if lasttoken == '.':
if parent is not __UNDEF__:
value = getattr(parent, token, __UNDEF__)
vars.append((prefix + token, prefix, value))
else:
where, value = lookup(token, frame, locals)
vars.append((token, where, value))
elif token == '.':
prefix += lasttoken + '.'
parent = value
else:
parent, prefix = None, ''
lasttoken = token
return vars
def html(einfo, context=5):
"""Return a nice HTML document describing a given traceback."""
import os, types, time, traceback, linecache, inspect, pydoc
etype, evalue, etb = einfo
if type(etype) is types.ClassType:
etype = etype.__name__
pyver = 'Python ' + sys.version.split()[0] + ': ' + sys.executable
date = time.ctime(time.time())
head = '<body bgcolor="#f0f0f8">' + pydoc.html.heading(
'<big><big>%s</big></big>' %
strong(pydoc.html.escape(str(etype))),
'#ffffff', '#6622aa', pyver + '<br>' + date) + '''
<p>A problem occurred in a Python script. Here is the sequence of
function calls leading up to the error, in the order they occurred.</p>'''
indent = '<tt>' + small('&nbsp;' * 5) + '&nbsp;</tt>'
frames = []
records = inspect.getinnerframes(etb, context)
for frame, file, lnum, func, lines, index in records:
if file:
file = os.path.abspath(file)
link = '<a href="file://%s">%s</a>' % (file, pydoc.html.escape(file))
else:
file = link = '?'
args, varargs, varkw, locals = inspect.getargvalues(frame)
call = ''
if func != '?':
call = 'in ' + strong(func) + \
inspect.formatargvalues(args, varargs, varkw, locals,
formatvalue=lambda value: '=' + pydoc.html.repr(value))
highlight = {}
def reader(lnum=[lnum]):
highlight[lnum[0]] = 1
try: return linecache.getline(file, lnum[0])
finally: lnum[0] += 1
vars = scanvars(reader, frame, locals)
rows = ['<tr><td bgcolor="#d8bbff">%s%s %s</td></tr>' %
('<big>&nbsp;</big>', link, call)]
if index is not None:
i = lnum - index
for line in lines:
num = small('&nbsp;' * (5-len(str(i))) + str(i)) + '&nbsp;'
line = '<tt>%s%s</tt>' % (num, pydoc.html.preformat(line))
if i in highlight:
rows.append('<tr><td bgcolor="#ffccee">%s</td></tr>' % line)
else:
rows.append('<tr><td>%s</td></tr>' % grey(line))
i += 1
done, dump = {}, []
for name, where, value in vars:
if name in done: continue
done[name] = 1
if value is not __UNDEF__:
if where in ('global', 'builtin'):
name = ('<em>%s</em> ' % where) + strong(name)
elif where == 'local':
name = strong(name)
else:
name = where + strong(name.split('.')[-1])
dump.append('%s&nbsp;= %s' % (name, pydoc.html.repr(value)))
else:
dump.append(name + ' <em>undefined</em>')
rows.append('<tr><td>%s</td></tr>' % small(grey(', '.join(dump))))
frames.append('''
<table width="100%%" cellspacing=0 cellpadding=0 border=0>
%s</table>''' % '\n'.join(rows))
exception = ['<p>%s: %s' % (strong(pydoc.html.escape(str(etype))),
pydoc.html.escape(str(evalue)))]
for name in dir(evalue):
if name[:1] == '_': continue
value = pydoc.html.repr(getattr(evalue, name))
exception.append('\n<br>%s%s&nbsp;=\n%s' % (indent, name, value))
import traceback
return head + ''.join(frames) + ''.join(exception) + '''
<!-- The above is a description of an error in a Python program, formatted
for a Web browser because the 'cgitb' module was enabled. In case you
are not reading this in a Web browser, here is the original traceback:
%s
-->
Merged revisions 55407-55513 via svnmerge from svn+ssh://pythondev@svn.python.org/python/branches/p3yk ................ r55413 | fred.drake | 2007-05-17 12:30:10 -0700 (Thu, 17 May 2007) | 1 line fix argument name in documentation; match the implementation ................ r55430 | jack.diederich | 2007-05-18 06:39:59 -0700 (Fri, 18 May 2007) | 1 line Implements class decorators, PEP 3129. ................ r55432 | guido.van.rossum | 2007-05-18 08:09:41 -0700 (Fri, 18 May 2007) | 2 lines obsubmit. ................ r55434 | guido.van.rossum | 2007-05-18 09:39:10 -0700 (Fri, 18 May 2007) | 3 lines Fix bug in test_inspect. (I presume this is how it should be fixed; Jack Diedrich, please verify.) ................ r55460 | brett.cannon | 2007-05-20 00:31:57 -0700 (Sun, 20 May 2007) | 4 lines Remove the imageop module. With imgfile already removed in Python 3.0 and rgbimg gone in Python 2.6 the unit tests themselves were made worthless. Plus third-party libraries perform the same function much better. ................ r55469 | neal.norwitz | 2007-05-20 11:28:20 -0700 (Sun, 20 May 2007) | 118 lines Merged revisions 55324-55467 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r55348 | georg.brandl | 2007-05-15 13:19:34 -0700 (Tue, 15 May 2007) | 4 lines HTML-escape the plain traceback in cgitb's HTML output, to prevent the traceback inadvertently or maliciously closing the comment and injecting HTML into the error page. ........ r55372 | neal.norwitz | 2007-05-15 21:33:50 -0700 (Tue, 15 May 2007) | 6 lines Port rev 55353 from Guido: Add what looks like a necessary call to PyErr_NoMemory() when PyMem_MALLOC() fails. Will backport. ........ r55377 | neal.norwitz | 2007-05-15 22:06:33 -0700 (Tue, 15 May 2007) | 1 line Mention removal of some directories for obsolete platforms ........ r55380 | brett.cannon | 2007-05-15 22:50:03 -0700 (Tue, 15 May 2007) | 2 lines Change the maintainer of the BeOS port. ........ r55383 | georg.brandl | 2007-05-16 06:44:18 -0700 (Wed, 16 May 2007) | 2 lines Bug #1719995: don't use deprecated method in sets example. ........ r55386 | neal.norwitz | 2007-05-16 13:05:11 -0700 (Wed, 16 May 2007) | 5 lines Fix bug in marshal where bad data would cause a segfault due to lack of an infinite recursion check. Contributed by Damien Miller at Google. ........ r55389 | brett.cannon | 2007-05-16 15:42:29 -0700 (Wed, 16 May 2007) | 6 lines Remove the gopherlib module. It has been raising a DeprecationWarning since Python 2.5. Also remove gopher support from urllib/urllib2. As both imported gopherlib the usage of the support would have raised a DeprecationWarning. ........ r55394 | raymond.hettinger | 2007-05-16 18:08:04 -0700 (Wed, 16 May 2007) | 1 line calendar.py gets no benefit from xrange() instead of range() ........ r55395 | brett.cannon | 2007-05-16 19:02:56 -0700 (Wed, 16 May 2007) | 3 lines Complete deprecation of BaseException.message. Some subclasses were directly accessing the message attribute instead of using the descriptor. ........ r55396 | neal.norwitz | 2007-05-16 23:11:36 -0700 (Wed, 16 May 2007) | 4 lines Reduce the max stack depth to see if this fixes the segfaults on Windows and some other boxes. If this is successful, this rev should be backported. I'm not sure how close to the limit we should push this. ........ r55397 | neal.norwitz | 2007-05-16 23:23:50 -0700 (Wed, 16 May 2007) | 4 lines Set the depth to something very small to try to determine if the crashes on Windows are really due to the stack size or possibly some other problem. ........ r55398 | neal.norwitz | 2007-05-17 00:04:46 -0700 (Thu, 17 May 2007) | 4 lines Last try for tweaking the max stack depth. 5000 was the original value, 4000 didn't work either. 1000 does work on Windows. If 2000 works, that will hopefully be a reasonable balance. ........ r55412 | fred.drake | 2007-05-17 12:29:58 -0700 (Thu, 17 May 2007) | 1 line fix argument name in documentation; match the implementation ........ r55427 | neal.norwitz | 2007-05-17 22:47:16 -0700 (Thu, 17 May 2007) | 1 line Verify neither dumps or loads overflow the stack and segfault. ........ r55446 | collin.winter | 2007-05-18 16:11:24 -0700 (Fri, 18 May 2007) | 1 line Backport PEP 3110's new 'except' syntax to 2.6. ........ r55448 | raymond.hettinger | 2007-05-18 18:11:16 -0700 (Fri, 18 May 2007) | 1 line Improvements to NamedTuple's implementation, tests, and documentation ........ r55449 | raymond.hettinger | 2007-05-18 18:50:11 -0700 (Fri, 18 May 2007) | 1 line Fix beginner mistake -- don't mix spaces and tabs. ........ r55450 | neal.norwitz | 2007-05-18 20:48:47 -0700 (Fri, 18 May 2007) | 1 line Clear data so random memory does not get freed. Will backport. ........ r55452 | neal.norwitz | 2007-05-18 21:34:55 -0700 (Fri, 18 May 2007) | 3 lines Whoops, need to pay attention to those test failures. Move the clear to *before* the first use, not after. ........ r55453 | neal.norwitz | 2007-05-18 21:35:52 -0700 (Fri, 18 May 2007) | 1 line Give some clue as to what happened if the test fails. ........ r55455 | georg.brandl | 2007-05-19 11:09:26 -0700 (Sat, 19 May 2007) | 2 lines Fix docstring for add_package in site.py. ........ r55458 | brett.cannon | 2007-05-20 00:09:50 -0700 (Sun, 20 May 2007) | 2 lines Remove the rgbimg module. It has been deprecated since Python 2.5. ........ r55465 | nick.coghlan | 2007-05-20 04:12:49 -0700 (Sun, 20 May 2007) | 1 line Fix typo in example (should be backported, but my maintenance branch is woefully out of date) ........ ................ r55472 | brett.cannon | 2007-05-20 12:06:18 -0700 (Sun, 20 May 2007) | 2 lines Remove imageop from the Windows build process. ................ r55486 | neal.norwitz | 2007-05-20 23:59:52 -0700 (Sun, 20 May 2007) | 1 line Remove callable() builtin ................ r55506 | neal.norwitz | 2007-05-22 00:43:29 -0700 (Tue, 22 May 2007) | 78 lines Merged revisions 55468-55505 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r55468 | neal.norwitz | 2007-05-20 11:06:27 -0700 (Sun, 20 May 2007) | 1 line rotor is long gone. ........ r55470 | neal.norwitz | 2007-05-20 11:43:00 -0700 (Sun, 20 May 2007) | 1 line Update directories/files at the top-level. ........ r55471 | brett.cannon | 2007-05-20 12:05:06 -0700 (Sun, 20 May 2007) | 2 lines Try to remove rgbimg from Windows builds. ........ r55474 | brett.cannon | 2007-05-20 16:17:38 -0700 (Sun, 20 May 2007) | 4 lines Remove the macfs module. This led to the deprecation of macostools.touched(); it completely relied on macfs and is a no-op on OS X according to code comments. ........ r55476 | brett.cannon | 2007-05-20 16:56:18 -0700 (Sun, 20 May 2007) | 3 lines Move imgfile import to the global namespace to trigger an import error ASAP to prevent creation of a test file. ........ r55477 | brett.cannon | 2007-05-20 16:57:38 -0700 (Sun, 20 May 2007) | 3 lines Cause posixfile to raise a DeprecationWarning. Documented as deprecated since Ptyhon 1.5. ........ r55479 | andrew.kuchling | 2007-05-20 17:03:15 -0700 (Sun, 20 May 2007) | 1 line Note removed modules ........ r55481 | martin.v.loewis | 2007-05-20 21:35:47 -0700 (Sun, 20 May 2007) | 2 lines Add Alexandre Vassalotti. ........ r55482 | george.yoshida | 2007-05-20 21:41:21 -0700 (Sun, 20 May 2007) | 4 lines fix against r55474 [Remove the macfs module] Remove "libmacfs.tex" from Makefile.deps and mac/mac.tex. ........ r55487 | raymond.hettinger | 2007-05-21 01:13:35 -0700 (Mon, 21 May 2007) | 1 line Replace assertion with straight error-checking. ........ r55489 | raymond.hettinger | 2007-05-21 09:40:10 -0700 (Mon, 21 May 2007) | 1 line Allow all alphanumeric and underscores in type and field names. ........ r55490 | facundo.batista | 2007-05-21 10:32:32 -0700 (Mon, 21 May 2007) | 5 lines Added timeout support to HTTPSConnection, through the socket.create_connection function. Also added a small test for this, and updated NEWS file. ........ r55495 | georg.brandl | 2007-05-21 13:34:16 -0700 (Mon, 21 May 2007) | 2 lines Patch #1686487: you can now pass any mapping after '**' in function calls. ........ r55502 | neal.norwitz | 2007-05-21 23:03:36 -0700 (Mon, 21 May 2007) | 1 line Document new params to HTTPSConnection ........ r55504 | neal.norwitz | 2007-05-22 00:16:10 -0700 (Tue, 22 May 2007) | 1 line Stop using METH_OLDARGS ........ r55505 | neal.norwitz | 2007-05-22 00:16:44 -0700 (Tue, 22 May 2007) | 1 line Stop using METH_OLDARGS implicitly ........ ................
2007-05-22 15:11:13 -03:00
''' % pydoc.html.escape(
''.join(traceback.format_exception(etype, evalue, etb)))
def text(einfo, context=5):
"""Return a plain text document describing a given traceback."""
import os, types, time, traceback, linecache, inspect, pydoc
etype, evalue, etb = einfo
if type(etype) is types.ClassType:
etype = etype.__name__
pyver = 'Python ' + sys.version.split()[0] + ': ' + sys.executable
date = time.ctime(time.time())
head = "%s\n%s\n%s\n" % (str(etype), pyver, date) + '''
A problem occurred in a Python script. Here is the sequence of
function calls leading up to the error, in the order they occurred.
'''
frames = []
records = inspect.getinnerframes(etb, context)
for frame, file, lnum, func, lines, index in records:
file = file and os.path.abspath(file) or '?'
args, varargs, varkw, locals = inspect.getargvalues(frame)
call = ''
if func != '?':
call = 'in ' + func + \
inspect.formatargvalues(args, varargs, varkw, locals,
formatvalue=lambda value: '=' + pydoc.text.repr(value))
highlight = {}
def reader(lnum=[lnum]):
highlight[lnum[0]] = 1
try: return linecache.getline(file, lnum[0])
finally: lnum[0] += 1
vars = scanvars(reader, frame, locals)
rows = [' %s %s' % (file, call)]
if index is not None:
i = lnum - index
for line in lines:
num = '%5d ' % i
rows.append(num+line.rstrip())
i += 1
done, dump = {}, []
for name, where, value in vars:
if name in done: continue
done[name] = 1
if value is not __UNDEF__:
if where == 'global': name = 'global ' + name
elif where != 'local': name = where + name.split('.')[-1]
dump.append('%s = %s' % (name, pydoc.text.repr(value)))
else:
dump.append(name + ' undefined')
rows.append('\n'.join(dump))
frames.append('\n%s\n' % '\n'.join(rows))
exception = ['%s: %s' % (str(etype), str(evalue))]
for name in dir(evalue):
value = pydoc.text.repr(getattr(evalue, name))
exception.append('\n%s%s = %s' % (" "*4, name, value))
import traceback
return head + ''.join(frames) + ''.join(exception) + '''
The above is a description of an error in a Python program. Here is
the original traceback:
%s
''' % ''.join(traceback.format_exception(etype, evalue, etb))
class Hook:
"""A hook to replace sys.excepthook that shows tracebacks in HTML."""
def __init__(self, display=1, logdir=None, context=5, file=None,
format="html"):
self.display = display # send tracebacks to browser if true
self.logdir = logdir # log tracebacks to files if not None
self.context = context # number of source code lines per frame
self.file = file or sys.stdout # place to send the output
self.format = format
def __call__(self, etype, evalue, etb):
self.handle((etype, evalue, etb))
def handle(self, info=None):
info = info or sys.exc_info()
if self.format == "html":
self.file.write(reset())
formatter = (self.format=="html") and html or text
plain = False
try:
doc = formatter(info, self.context)
except: # just in case something goes wrong
import traceback
doc = ''.join(traceback.format_exception(*info))
plain = True
if self.display:
if plain:
doc = doc.replace('&', '&amp;').replace('<', '&lt;')
self.file.write('<pre>' + doc + '</pre>\n')
else:
self.file.write(doc + '\n')
else:
self.file.write('<p>A problem occurred in a Python script.\n')
if self.logdir is not None:
import os, tempfile
suffix = ['.txt', '.html'][self.format=="html"]
(fd, path) = tempfile.mkstemp(suffix=suffix, dir=self.logdir)
try:
file = os.fdopen(fd, 'w')
file.write(doc)
file.close()
msg = '<p> %s contains the description of this error.' % path
except:
msg = '<p> Tried to save traceback to %s, but failed.' % path
self.file.write(msg + '\n')
try:
self.file.flush()
except: pass
handler = Hook().handle
def enable(display=1, logdir=None, context=5, format="html"):
"""Install an exception handler that formats tracebacks as HTML.
The optional argument 'display' can be set to 0 to suppress sending the
traceback to the browser, and 'logdir' can be set to a directory to cause
tracebacks to be written to files there."""
sys.excepthook = Hook(display=display, logdir=logdir,
context=context, format=format)