Using real issues encountered in the wild, this session will help beginning integrators gain confidence in knowing what to do when Plone fails to behave as expected. Learn how to solve common problems like "My changes aren't taking effect" and "My Zope instance won't start," as well as how to use pdb to investigate more complex Python errors. This talk is targeted at integrators who have some experience with Plone, but who are not confident in troubleshooting errors and other unexpected behavior. Knowledge of Python is not required, though at least a cursory familiarity with some programming language will make the talk more digestible.

1. When Good Code Goes Bad: Tools and Techniques for Troubleshooting Plone Plone Conference 2008 David Glick Web Developer ONE/Northwest

5. Newbie programmer's reaction: Absolute terror

6. Experienced programmer's reaction: Absolute terror

7. Maybe it's a little bug...

8. ...but who knows what's in there, really!

10. Mental preparation

11. Remember: You are in control.

12. Remember: You are not alone.

13. Use the source, Luke.

14. Getting ready...

18. Stop ignoring errors in /error_log

19. Debugging tools

20. 1. What is that thing?

24. 2. What code controls this?

28. 3. What's that code doing?

30. pdb: the Python debugger

36. Reading a traceback (cont'd) For page template expressions Template file location The actual TAL expression that was called Location of expression within the template The actual Error message! Bonus (but irrelevant) error The Error happened here!

40. Lessons from Case #1

49. Lessons from Case #2

52. Tips and Tricks

60. Common red herrings