================
Debugging System
================

Depending on the WSGI gateway/server, exceptions are handled differently.  But
most of the time, exceptions go to stderr or the error log.

Since this is not the best debugging environment, Werkzeug provides a WSGI
middleware that renders nice debugging tracebacks, optionally with an AJAX
based debugger (which allows to execute code in the context of the
traceback's frames).

Usage:

.. sourcecode:: python

    from werkzeug import DebuggedApplication, run_simple
    from myapplication import application

    application = DebuggedApplication(application, evalex=True)
    
    run_simple('localhost', 5000, application)

This code spawns a debugging server on `localhost:5000` with the debugger
enabled.  If you set `evalex` to `False`, the debugger is disabled.

.. warning::

   Don't ever use the debugging middleware in a production environment since it
   can leak internal information that is part of the variable debug table.
   Even worse is a debugger with the `evalex` feature enabled, since it can be
   used to execute code on the server!