"""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 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. """ import inspect import keyword import linecache import os import pydoc import sys import tempfile import time import tokenize import traceback from html import escape as html_escape def reset(): """Return a string that resets the CGI and browser to a known state.""" return '''
--> --> ''' __UNDEF__ = [] # a special sentinel object def small(text): if text: return '' + text + '' else: return '' def strong(text): if text: return '' + text + '' else: return '' def grey(text): if text: return '' + text + '' 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.""" 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.""" etype, evalue, etb = einfo if isinstance(etype, type): etype = etype.__name__ pyver = 'Python ' + sys.version.split()[0] + ': ' + sys.executable date = time.ctime(time.time()) head = f''' {html_escape(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.
''' indent = '' + small(' ' * 5) + ' ' frames = [] records = inspect.getinnerframes(etb, context) for frame, file, lnum, func, lines, index in records: if file: file = os.path.abspath(file) link = '%s' % (file, pydoc.html.escape(file)) else: file = link = '?' args, varargs, varkw, locals = inspect.getargvalues(frame) call = '' if func != '?': call = 'in ' + strong(pydoc.html.escape(func)) if func != "%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 A problem occurred in a Python script.\n')
if self.logdir is not None:
suffix = ['.txt', '.html'][self.format=="html"]
(fd, path) = tempfile.mkstemp(suffix=suffix, dir=self.logdir)
try:
with os.fdopen(fd, 'w') as file:
file.write(doc)
msg = '%s contains the description of this error.' % path
except:
msg = 'Tried to save traceback to %s, but failed.' % path
if self.format == 'html':
self.file.write(' %s
%s%s =\n%s' % (indent, name, value))
return head + ''.join(frames) + ''.join(exception) + '''
''' % pydoc.html.escape(
''.join(traceback.format_exception(etype, evalue, etb)))
def text(einfo, context=5):
"""Return a plain text document describing a given traceback."""
etype, evalue, etb = einfo
if isinstance(etype, type):
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
if func != "' + doc + '
\n')
else:
self.file.write(doc + '\n')
else:
self.file.write('