[Grok-dev] various balls grok has in the air (and help us catch them)

[Sebastian Ware]

Just reposting:

** Debugging ***

You can debug your application using the python debugger (Pdb). If  
you want to explore why you are getting an unexpected exception you  
are better off using post-mortem debugging (se separate topic).

1 First you have to import the pdb module

   import pdb

2 Then you set a breakpoint in your code by inserting the following  
line of code

   pdb.set_trace()

3 Run the application from a terminal

   parts/instance/bin/runzope

4 Play around with your application until the execution reaches the  
breakpoint

5 In the terminal window where you started Zope you will now se the  
python debugger prompt

   (Pdb)

6 Check out the available commands in Pdb

   http://docs.python.org/lib/debugger-commands.html
   http://docs.python.org/lib/debugger-hooks.html

mvh Sebastian

*** Post-mortem Debugging ***

Post-mortem debugging allows you to explore the state of your  
application once it has thrown an exception. In order to enable post- 
mortem debugging:

1 in your buildout.cfg look for the zopectl section. You will see an  
entry
there that defines the zope.conf that should be used. Modify that to
look like this:

   zope.conf = ${data:zconfig}
       <server>
          type PostmortemDebuggingHTTP
          address 8080
       </server>

if you rerun buildout your zope.conf will be updated to use the
PostmortemDebuggingHTTP server.


2 Start Zope in a terminal

   parts/instance/bin/runzope

3 Use the application up to the point of the exception

4 Trigger the post-mortem debugger by opening the following page in  
your browser

   http://localhost:9000/
   -given server on localhost and the port in (1) set to 9000

5 In the terminal window where you started Zope you will now see the  
python debugger prompt

   (Pdb)

6 Check out the available commands in Pdb

   http://docs.python.org/lib/debugger-commands.html
   http://docs.python.org/lib/debugger-hooks.html

Mvh Sebastian (and a correction posted by Wichert)


10 sep 2007 kl. 22.51 skrev Martijn Faassen:

> * Sebastian and Wichert wrote some instructions on post-mortem
> debugging. Is there something still blocking this from appearing as a
> tutorial on our website?