/usr/lib/python2.7/cgitb.py is in libpython2.7-stdlib 2.7.11-7ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
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 | """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
import types
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."""
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 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(' ' * 5) + ' </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> </big>', link, call)]
if index is not None:
i = lnum - index
for line in lines:
num = small(' ' * (5-len(str(i))) + str(i)) + ' '
if i in highlight:
line = '<tt>=>%s%s</tt>' % (num, pydoc.html.preformat(line))
rows.append('<tr><td bgcolor="#ffccee">%s</td></tr>' % line)
else:
line = '<tt> %s%s</tt>' % (num, pydoc.html.preformat(line))
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 = %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)))]
if isinstance(evalue, BaseException):
for name in dir(evalue):
if name[:1] == '_': continue
value = pydoc.html.repr(getattr(evalue, name))
exception.append('\n<br>%s%s =\n%s' % (indent, name, value))
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
-->
''' % 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 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))]
if isinstance(evalue, BaseException):
for name in dir(evalue):
value = pydoc.text.repr(getattr(evalue, name))
exception.append('\n%s%s = %s' % (" "*4, name, value))
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
doc = ''.join(traceback.format_exception(*info))
plain = True
if self.display:
if plain:
doc = doc.replace('&', '&').replace('<', '<')
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:
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 = '%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('<p>%s</p>\n' % msg)
else:
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)
|