SF Patch 569574 - enhancements to cgitb for plain text display
diff --git a/Lib/cgitb.py b/Lib/cgitb.py
index 200e8ee..4e0c9fb 100644
--- a/Lib/cgitb.py
+++ b/Lib/cgitb.py
@@ -1,20 +1,25 @@
-"""Handle exceptions in CGI scripts by formatting tracebacks into nice HTML.
+"""More comprehensive traceback formatting for Python scripts.
To enable this module, do:
import cgitb; cgitb.enable()
-at the top of your CGI script. The optional arguments to enable() are:
+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, and context is 5.
+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()."""
+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__ = '$Revision$'
@@ -160,30 +165,105 @@
-->
''' % ''.join(traceback.format_exception(etype, evalue, etb))
+def text((etype, evalue, etb), context=5):
+ """Return a plain text document describing a given traceback."""
+ import os, types, time, traceback, linecache, inspect, pydoc
+
+ 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 = name
+ else: 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 type(evalue) is types.InstanceType:
+ 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):
+ 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()
- self.file.write(reset())
+ if self.format == "html":
+ self.file.write(reset())
+ formatter = (self.format=="html") and html or text
+ plain = False
try:
- text, doc = 0, html(info, self.context)
+ doc = formatter(info, self.context)
except: # just in case something goes wrong
import traceback
- text, doc = 1, ''.join(traceback.format_exception(*info))
+ doc = ''.join(traceback.format_exception(*info))
+ plain = True
if self.display:
- if text:
+ if plain:
doc = doc.replace('&', '&').replace('<', '<')
self.file.write('<pre>' + doc + '</pre>\n')
else:
@@ -193,8 +273,8 @@
if self.logdir is not None:
import os, tempfile
- (fd, path) = tempfile.mkstemp(suffix=['.html', '.txt'][text],
- dir=self.logdir)
+ suffix = ['.html', '.txt'][self.format=="html"]
+ (fd, path) = tempfile.mkstemp(suffix=suffix, dir=self.logdir)
try:
file = os.fdopen(fd, 'w')
file.write(doc)
@@ -208,10 +288,11 @@
except: pass
handler = Hook().handle
-def enable(display=1, logdir=None, context=5):
+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, logdir, context)
+ sys.excepthook = Hook(display=display, logdir=logdir,
+ context=context, format=format)