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gerrit-public.fairphone.software / platform / external / python / cpython2 / d9e0e1f42259b81a5ab3e2825df5b9a64560b5cd / . / Lib / cgitb.py
blob: 2602d57e7bc5fbf4c02103084cde72f1fd8a0315 [file] [log] [blame]
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]1"""Handle exceptions in CGI scripts by formatting tracebacks into nice HTML.
2
3To enable this module, do:
4
5 import cgitb; cgitb.enable()
6
7at the top of your CGI script. The optional arguments to enable() are:
8
9 display - if true, tracebacks are displayed in the web browser
10 logdir - if set, tracebacks are written to files in this directory
Ka-Ping Yee83205972001-08-21 06:53:01 +0000[diff] [blame]11 context - number of lines of source code to show for each stack frame
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]12
Ka-Ping Yee83205972001-08-21 06:53:01 +0000[diff] [blame]13By default, tracebacks are displayed but not saved, and context is 5.
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]14
15Alternatively, if you have caught an exception and want cgitb to display it
Fred Drake4f5b49f2001-12-19 14:27:41 +0000[diff] [blame]16for you, call cgitb.handler(). The optional argument to handler() is a 3-item
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]17tuple (etype, evalue, etb) just like the value of sys.exc_info()."""
18
19__author__ = 'Ka-Ping Yee'
20__version__ = '$Revision$'
21
Ka-Ping Yeefa78d0f2001-12-04 18:45:17 +0000[diff] [blame]22import sys
23
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]24def reset():
25 """Return a string that resets the CGI and browser to a known state."""
26 return '''<!--: spam
27Content-Type: text/html
28
Ka-Ping Yee83205972001-08-21 06:53:01 +0000[diff] [blame]29<body bgcolor="#f0f0f8"><font color="#f0f0f8" size="-5"> -->
30<body bgcolor="#f0f0f8"><font color="#f0f0f8" size="-5"> --> -->
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]31</font> </font> </font> </script> </object> </blockquote> </pre>
32</table> </table> </table> </table> </table> </font> </font> </font>'''
33
Ka-Ping Yee83205972001-08-21 06:53:01 +0000[diff] [blame]34__UNDEF__ = [] # a special sentinel object
35def small(text): return '<small>' + text + '</small>'
36def strong(text): return '<strong>' + text + '</strong>'
37def grey(text): return '<font color="#909090">' + text + '</font>'
38
39def lookup(name, frame, locals):
40 """Find the value for a given name in the given environment."""
41 if name in locals:
42 return 'local', locals[name]
43 if name in frame.f_globals:
44 return 'global', frame.f_globals[name]
Ka-Ping Yee711cad72002-06-26 07:10:56 +0000[diff] [blame]45 if '__builtins__' in frame.f_globals:
46 builtins = frame.f_globals['__builtins__']
47 if type(builtins) is type({}):
48 if name in builtins:
49 return 'builtin', builtins[name]
50 else:
51 if hasattr(builtins, name):
52 return 'builtin', getattr(builtins, name)
Ka-Ping Yee83205972001-08-21 06:53:01 +0000[diff] [blame]53 return None, __UNDEF__
54
55def scanvars(reader, frame, locals):
56 """Scan one logical line of Python and look up values of variables used."""
57 import tokenize, keyword
58 vars, lasttoken, parent, prefix = [], None, None, ''
59 for ttype, token, start, end, line in tokenize.generate_tokens(reader):
60 if ttype == tokenize.NEWLINE: break
61 if ttype == tokenize.NAME and token not in keyword.kwlist:
62 if lasttoken == '.':
63 if parent is not __UNDEF__:
64 value = getattr(parent, token, __UNDEF__)
65 vars.append((prefix + token, prefix, value))
66 else:
67 where, value = lookup(token, frame, locals)
68 vars.append((token, where, value))
69 elif token == '.':
70 prefix += lasttoken + '.'
71 parent = value
72 else:
73 parent, prefix = None, ''
74 lasttoken = token
75 return vars
76
77def html((etype, evalue, etb), context=5):
78 """Return a nice HTML document describing a given traceback."""
Ka-Ping Yeefa78d0f2001-12-04 18:45:17 +0000[diff] [blame]79 import os, types, time, traceback, linecache, inspect, pydoc
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]80
81 if type(etype) is types.ClassType:
82 etype = etype.__name__
83 pyver = 'Python ' + sys.version.split()[0] + ': ' + sys.executable
84 date = time.ctime(time.time())
Ka-Ping Yee83205972001-08-21 06:53:01 +0000[diff] [blame]85 head = '<body bgcolor="#f0f0f8">' + pydoc.html.heading(
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]86 '<big><big><strong>%s</strong></big></big>' % str(etype),
Ka-Ping Yee83205972001-08-21 06:53:01 +0000[diff] [blame]87 '#ffffff', '#6622aa', pyver + '<br>' + date) + '''
88<p>A problem occurred in a Python script. Here is the sequence of
89function calls leading up to the error, in the order they occurred.'''
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]90
Ka-Ping Yee83205972001-08-21 06:53:01 +0000[diff] [blame]91 indent = '<tt>' + small('&nbsp;' * 5) + '&nbsp;</tt>'
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]92 frames = []
93 records = inspect.getinnerframes(etb, context)
94 for frame, file, lnum, func, lines, index in records:
95 file = file and os.path.abspath(file) or '?'
Ka-Ping Yee83205972001-08-21 06:53:01 +0000[diff] [blame]96 link = '<a href="file://%s">%s</a>' % (file, pydoc.html.escape(file))
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]97 args, varargs, varkw, locals = inspect.getargvalues(frame)
Ka-Ping Yee83205972001-08-21 06:53:01 +0000[diff] [blame]98 call = ''
99 if func != '?':
100 call = 'in ' + strong(func) + \
101 inspect.formatargvalues(args, varargs, varkw, locals,
102 formatvalue=lambda value: '=' + pydoc.html.repr(value))
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]103
Ka-Ping Yee83205972001-08-21 06:53:01 +0000[diff] [blame]104 highlight = {}
105 def reader(lnum=[lnum]):
106 highlight[lnum[0]] = 1
107 try: return linecache.getline(file, lnum[0])
108 finally: lnum[0] += 1
109 vars = scanvars(reader, frame, locals)
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]110
Ka-Ping Yee83205972001-08-21 06:53:01 +0000[diff] [blame]111 rows = ['<tr><td bgcolor="#d8bbff">%s%s %s</td></tr>' %
112 ('<big>&nbsp;</big>', link, call)]
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]113 if index is not None:
114 i = lnum - index
115 for line in lines:
Ka-Ping Yee83205972001-08-21 06:53:01 +0000[diff] [blame]116 num = small('&nbsp;' * (5-len(str(i))) + str(i)) + '&nbsp;'
117 line = '<tt>%s%s</tt>' % (num, pydoc.html.preformat(line))
118 if i in highlight:
119 rows.append('<tr><td bgcolor="#ffccee">%s</td></tr>' % line)
120 else:
121 rows.append('<tr><td>%s</td></tr>' % grey(line))
122 i += 1
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]123
Ka-Ping Yee83205972001-08-21 06:53:01 +0000[diff] [blame]124 done, dump = {}, []
125 for name, where, value in vars:
126 if name in done: continue
127 done[name] = 1
128 if value is not __UNDEF__:
Ka-Ping Yee711cad72002-06-26 07:10:56 +0000[diff] [blame]129 if where in ['global', 'builtin']:
130 name = ('<em>%s</em> ' % where) + strong(name)
131 elif where == 'local':
132 name = strong(name)
133 else:
134 name = where + strong(name.split('.')[-1])
Ka-Ping Yee83205972001-08-21 06:53:01 +0000[diff] [blame]135 dump.append('%s&nbsp;= %s' % (name, pydoc.html.repr(value)))
136 else:
137 dump.append(name + ' <em>undefined</em>')
138
139 rows.append('<tr><td>%s</td></tr>' % small(grey(', '.join(dump))))
140 frames.append('''<p>
141<table width="100%%" cellspacing=0 cellpadding=0 border=0>
142%s</table>''' % '\n'.join(rows))
143
144 exception = ['<p>%s: %s' % (strong(str(etype)), str(evalue))]
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]145 if type(evalue) is types.InstanceType:
146 for name in dir(evalue):
Ka-Ping Yee711cad72002-06-26 07:10:56 +0000[diff] [blame]147 if name[:1] == '_': continue
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]148 value = pydoc.html.repr(getattr(evalue, name))
149 exception.append('\n<br>%s%s&nbsp;=\n%s' % (indent, name, value))
150
151 import traceback
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]152 return head + ''.join(frames) + ''.join(exception) + '''
153
154
Ka-Ping Yee83205972001-08-21 06:53:01 +0000[diff] [blame]155<!-- The above is a description of an error in a Python program, formatted
156 for a Web browser because the 'cgitb' module was enabled. In case you
157 are not reading this in a Web browser, here is the original traceback:
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]158
159%s
160-->
Ka-Ping Yee83205972001-08-21 06:53:01 +0000[diff] [blame]161''' % ''.join(traceback.format_exception(etype, evalue, etb))
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]162
163class Hook:
Ka-Ping Yee83205972001-08-21 06:53:01 +0000[diff] [blame]164 """A hook to replace sys.excepthook that shows tracebacks in HTML."""
165
Ka-Ping Yeefa78d0f2001-12-04 18:45:17 +0000[diff] [blame]166 def __init__(self, display=1, logdir=None, context=5, file=None):
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]167 self.display = display # send tracebacks to browser if true
168 self.logdir = logdir # log tracebacks to files if not None
Ka-Ping Yee83205972001-08-21 06:53:01 +0000[diff] [blame]169 self.context = context # number of source code lines per frame
Ka-Ping Yeefa78d0f2001-12-04 18:45:17 +0000[diff] [blame]170 self.file = file or sys.stdout # place to send the output
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]171
172 def __call__(self, etype, evalue, etb):
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]173 self.handle((etype, evalue, etb))
174
175 def handle(self, info=None):
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]176 info = info or sys.exc_info()
Ka-Ping Yeefa78d0f2001-12-04 18:45:17 +0000[diff] [blame]177 self.file.write(reset())
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]178
179 try:
Ka-Ping Yee83205972001-08-21 06:53:01 +0000[diff] [blame]180 text, doc = 0, html(info, self.context)
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]181 except: # just in case something goes wrong
182 import traceback
Ka-Ping Yee83205972001-08-21 06:53:01 +0000[diff] [blame]183 text, doc = 1, ''.join(traceback.format_exception(*info))
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]184
185 if self.display:
186 if text:
187 doc = doc.replace('&', '&amp;').replace('<', '&lt;')
Ka-Ping Yeefa78d0f2001-12-04 18:45:17 +0000[diff] [blame]188 self.file.write('<pre>' + doc + '</pre>\n')
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]189 else:
Ka-Ping Yeefa78d0f2001-12-04 18:45:17 +0000[diff] [blame]190 self.file.write(doc + '\n')
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]191 else:
Ka-Ping Yeefa78d0f2001-12-04 18:45:17 +0000[diff] [blame]192 self.file.write('<p>A problem occurred in a Python script.\n')
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]193
194 if self.logdir is not None:
Ka-Ping Yee83205972001-08-21 06:53:01 +0000[diff] [blame]195 import os, tempfile
Guido van Rossum3b0a3292002-08-09 16:38:32 +0000[diff] [blame]196 (fd, name) = tempfile.mkstemp(suffix=['.html', '.txt'][text],
197 dir=self.logdir)
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]198 try:
Guido van Rossum3b0a3292002-08-09 16:38:32 +0000[diff] [blame]199 file = os.fdopen(fd, 'w')
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]200 file.write(doc)
201 file.close()
Ka-Ping Yeefa78d0f2001-12-04 18:45:17 +0000[diff] [blame]202 msg = '<p> %s contains the description of this error.' % path
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]203 except:
Ka-Ping Yeefa78d0f2001-12-04 18:45:17 +0000[diff] [blame]204 msg = '<p> Tried to save traceback to %s, but failed.' % path
205 self.file.write(msg + '\n')
206 try:
207 self.file.flush()
208 except: pass
Ka-Ping Yee6b5a48d2001-08-18 04:04:50 +0000[diff] [blame]209
210handler = Hook().handle
Ka-Ping Yee83205972001-08-21 06:53:01 +0000[diff] [blame]211def enable(display=1, logdir=None, context=5):
212 """Install an exception handler that formats tracebacks as HTML.
213
214 The optional argument 'display' can be set to 0 to suppress sending the
215 traceback to the browser, and 'logdir' can be set to a directory to cause
216 tracebacks to be written to files there."""
Ka-Ping Yee83205972001-08-21 06:53:01 +0000[diff] [blame]217 sys.excepthook = Hook(display, logdir, context)