1 :mod:`cgitb` --- Traceback manager for CGI scripts 2 ================================================== 3 4 .. module:: cgitb 5 :synopsis: Configurable traceback handler for CGI scripts. 6 7 .. moduleauthor:: Ka-Ping Yee <ping (a] lfw.org> 8 .. sectionauthor:: Fred L. Drake, Jr. <fdrake (a] acm.org> 9 10 **Source code:** :source:`Lib/cgitb.py` 11 12 .. index:: 13 single: CGI; exceptions 14 single: CGI; tracebacks 15 single: exceptions; in CGI scripts 16 single: tracebacks; in CGI scripts 17 18 -------------- 19 20 The :mod:`cgitb` module provides a special exception handler for Python scripts. 21 (Its name is a bit misleading. It was originally designed to display extensive 22 traceback information in HTML for CGI scripts. It was later generalized to also 23 display this information in plain text.) After this module is activated, if an 24 uncaught exception occurs, a detailed, formatted report will be displayed. The 25 report includes a traceback showing excerpts of the source code for each level, 26 as well as the values of the arguments and local variables to currently running 27 functions, to help you debug the problem. Optionally, you can save this 28 information to a file instead of sending it to the browser. 29 30 To enable this feature, simply add this to the top of your CGI script:: 31 32 import cgitb 33 cgitb.enable() 34 35 The options to the :func:`enable` function control whether the report is 36 displayed in the browser and whether the report is logged to a file for later 37 analysis. 38 39 40 .. function:: enable(display=1, logdir=None, context=5, format="html") 41 42 .. index:: single: excepthook() (in module sys) 43 44 This function causes the :mod:`cgitb` module to take over the interpreter's 45 default handling for exceptions by setting the value of :attr:`sys.excepthook`. 46 47 The optional argument *display* defaults to ``1`` and can be set to ``0`` to 48 suppress sending the traceback to the browser. If the argument *logdir* is 49 present, the traceback reports are written to files. The value of *logdir* 50 should be a directory where these files will be placed. The optional argument 51 *context* is the number of lines of context to display around the current line 52 of source code in the traceback; this defaults to ``5``. If the optional 53 argument *format* is ``"html"``, the output is formatted as HTML. Any other 54 value forces plain text output. The default value is ``"html"``. 55 56 57 .. function:: text(info, context=5) 58 59 This function handles the exception described by *info* (a 3-tuple containing 60 the result of :func:`sys.exc_info`), formatting its traceback as text and 61 returning the result as a string. The optional argument *context* is the 62 number of lines of context to display around the current line of source code 63 in the traceback; this defaults to ``5``. 64 65 66 .. function:: html(info, context=5) 67 68 This function handles the exception described by *info* (a 3-tuple containing 69 the result of :func:`sys.exc_info`), formatting its traceback as HTML and 70 returning the result as a string. The optional argument *context* is the 71 number of lines of context to display around the current line of source code 72 in the traceback; this defaults to ``5``. 73 74 75 .. function:: handler(info=None) 76 77 This function handles an exception using the default settings (that is, show a 78 report in the browser, but don't log to a file). This can be used when you've 79 caught an exception and want to report it using :mod:`cgitb`. The optional 80 *info* argument should be a 3-tuple containing an exception type, exception 81 value, and traceback object, exactly like the tuple returned by 82 :func:`sys.exc_info`. If the *info* argument is not supplied, the current 83 exception is obtained from :func:`sys.exc_info`. 84 85
