Sep 09, 2011 Slides of Fabrizio Branca's talk on the TYPO3 Developer Days 2010 (T3DD10)

1. Debugging, Monitoring and
Profiling
Fabrizio Branca
fabrizio (dot) branca (at) aoemedia (dot) de
Twitter: @fbrnc

2. This talk is…
• sharing some best practices
• sharing some tools with you
• an (incomplete) checklist
• a reminder (hopefully)
Fabrizio Branca

3. What is this all about?
• Make your website run smoothly!
• during development…
• and when the site is online
• “Smoothly” is
• No bugs (unexpected behaviour)
• Stability
• Performance
Fabrizio Branca

4. This talk is about
How to…
• avoid errors
• detect errors
• deal with errors
• notify yourself when errors have occurred
Fabrizio Branca

5. It„s all about bugs
Fabrizio Branca

6. It„s all about bugs
Everybody creates bugs. Nobody is perfect.
A high percentage of coding time goes into
• searching for bugs
• fixing bugs
Increase your productivity by reducing this time!
Fabrizio Branca

7. Automating
• Automatize error recognition
• Use proper tools
• Automatize error reporting
• Route detailed error reports into your mailbox
Fabrizio Branca

8. Bugs
• Avoid bugs
• through programming style
• Spot bugs fast
• “Safety nets”: Unit tests, Assertions
• Detect them before the customer and/or
the website user finds them
Fabrizio Branca

9. Avoid bugs
• Use a proper IDE
• Syntax checks
• Code Completion

10. Coding style
• Cover all cases: No if without else!
• Use type hints wherever possible
• Stick to patterns
• Increase crearity
• Convention over configuration
• KISS
• Use object collections
• Make it easier for team members to find and fix bugs
(increase the truck factor) by sticking to coding
guidelines and patterns
Fabrizio Branca

11. What does PHP offer?
• log_errors
• display_errors
• error_log
Set values in
• php.ini
• .htaccess / vhost configuration
Fabrizio Branca

12. What does TYPO3 offer?
• devLog, sysLog, Tslog
• devIpMask
• Deprecation log
• Page not found / Page unavailable
• Exception handling
• Error handling
• Debug Console in the BE
Fabrizio Branca

13. Deal with exceptions (I)
How to react when an exception has
occurred?
• Don„t display any details to the user!
• Send a correct HTTP status code (for
search engines and log files)
$GLOBALS['TSFE']->pageNotFoundAndExit($errorHandlerMessage);
$GLOBALS['TSFE']->pageUnavailableAndExit($errorHandlerMessage);
Fabrizio Branca

14. Page not found
Fabrizio Branca

15. Page unavailable
Fabrizio Branca

16. Deal with exceptions (II)
Handle exceptions within your controllers.
Notify yourself:
• write a message to devLog
• write a message to sysLog
• write a message to TSLog
Fabrizio Branca

17. Exception Handler
Fabrizio Branca

18. Bug detection
• Bugs are harder to fix the later they are
detected
• Bugs become harder to diagnose the
further the symptom is removed from the
cause
Fabrizio Branca

19. Bug detection with assertions
• Make sure that variables contain what you
expect at any time (e.g. after calling a function)
• E.g.: Check incoming parameters for correct
type
• Simple one line call:
tx_pttools_assert::isValidUid($this->params['uid']);
• Throws an exception if assertion is not true
• http://articles.sitepoint.com/article/bug-detection-php-assertions
http://debuggable.com/posts/assert-the-yummyness-of-your-cake:480f4dd6-
7fe0-4113-9776-458acbdd56cb
Fabrizio Branca

20. Bug detection with assertions
• Assertions are easy to use.
• Don„t assume anything, check it!
• Example: ini_set()
• No substitute for unit tests!
Fabrizio Branca

21. Bug detection with assertions
See
EXT:pt_tools/res/staticlib/class.tx_pttools_assert.php
or
build your own assert class
Some examples:
• tx_pttools_assert::isValidUid();
• tx_pttools_assert::isNotEmptyString();
Fabrizio Branca

23. t3lib_div::devLog()
Fabrizio Branca

24. t3lib_div::sysLog()
Decides by configuration how to handle
syslog messages
• send mail
• write to log file
• write to OS syslog
Fabrizio Branca

25. Custom SysLog Handler
See
EXT:tcaobjects/res/class.tx_tcaobjects_syslog.php
Fabrizio Branca

26. SysLog notification mail
msg: Assertion "isValidUid" failed!
extKey: pt_tools
severity: 3
exceptionClass: tx_pttools_exceptionAssertion
debugMsg:
file: /var/www/burghalle/integration/htdocs/typo3conf/ext/aoe_burg/controller/class.tx_aoeburg_controller_extranet.php
line: 78
function: tx_aoeburg_controller_extranet::init
assertType: isValidUid
val:
expected: 1
Server:
TYPO3_REQUEST_URL: http://www.integration.burghalle.aoe-works.de/xtranet/uebersicht/artikel-
bearbeiten/e/typo3conf/ext/burghalle_template/i/white-75.png
HTTP_REFERER: http://www.integration.burghalle.aoe-works.de/xtranet/uebersicht/artikel-bearbeiten/e/saveContent.html
POST: -- none --
COOKIE:
condensed: 0
fe_typo_user: 6b7ccec749891321cb6e7e2fc4c685a4
PHPSESSID: 4b8712f5a4c845029da1f2332cf9132b
Client:
HTTP_USER_AGENT: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.4) Gecko/20100611 Firefox/3.6.4 ( .NET CLR
3.5.30729; .NET4.0C)
Spider: No
REMOTE_HOST: [null]
REMOTE_ADDR: 217.19.187.106
User:
FE_User: aoe
BE_User: -- no user --
Trace: [...]

27. $TYPO3_DB-
>debug_check_recordset()
• Check all database queries
• Debug_check_recordset takes care of
writing log messages
Fabrizio Branca

28. TSlog
Fabrizio Branca

29. $TT->push() / ->pull()
Use the timetrack object to keep track of
what happens in your code.
Fabrizio Branca

30. Reports module
Fabrizio Branca

31. Reports module
Write your own reports
Examples:
• Table size
• Outdated extensions (extension manager)
• TCA Integrity
• TCA/database integrity (Like Compare tool)
• Extension integrity (dependencies, conflicts)
• Free disk space
• Server load
Fabrizio Branca

32. Define a strong api
• Provide interfaces for hooks.
• Allow alternatives (pagerStrategy,
viewClass,…)
Fabrizio Branca

33. Keep an eye on the logs…
• Webserver
• Apache error log
• PHP error log
• TYPO3
• Log module (Core error handler…)
• Admin Panel
• RealUrl
• error log
• are all paramters encoded?
• Deprecation log
• Reports module
Fabrizio Branca

34. Keep an eye on the logs…
• External tools
• Google Webmaster Tools
• Wget
• Piwik
• MySQL
• Slow query log
• OS (*nix)
• Syslog
Fabrizio Branca

35. Log Module
Fabrizio Branca

37. Google Webmaster Tools
Fabrizio Branca

38. Let tools do the analysis
• PHP
• TSFE
• TypoScript
• jQuery code
• HTML
• CSS
• RSS
Fabrizio Branca

39. Visualizing xdebug profiling

40. Visualizing xdebug profiling

41. Visualizing pdepend xml

42. jQuery Lint
„Runtime Reporter“
http://james.padolsey.com/javascript/jquery-lint/
Fabrizio Branca

43. TypoScript Check (lint)
Proof of concept!
Xclassing tslib_content:
function stdWrap($content,$conf) {
$this->getLinkChecker()->check($conf, 'stdWrap');
return parent::stdWrap($content, $conf);
}
Fabrizio Branca

44. Tick

45. Tick
Fabrizio Branca

46. Tick

47. Use validators
Use validators for validating
• HTML
• CSS
• RSS
Keep an eye on editor„s content
Fabrizio Branca

48. Spot performance killers
• Use USER_INTs only if really needed.
• Create links with cHashes
• Avoid putting USER_INTs on all pages
(load them via ajax)
• Cache headers
• Static publishing
Fabrizio Branca

49. Monitoring
• Configure your TYPO3 instances to notify
you when errors occur.
• Use Monitoring tools (e.g. Nagios,
Caretaker?)
Fabrizio Branca

50. Pingdom

51. Maintainance
• Delete old temp files
find ../htdocs/typo3temp -type f -mtime +28 -delete
• Delete deleted records
• Delete unreferenced files
• Cleanup/check database
Fabrizio Branca