The Debug Dance - An Intro To Step Debugging - php[world] 2018

This talk was given at php[world] 2018.

Using `var_dump()` to debug your app has its benefits, but there are more comprehensive and efficient ways to debug those particularly illusive bugs. Enter step debugging. We'll be using Xdebug & the PhpStorm IDE to step through our PHP apps line by line and see how much more power step debugging gives us over the conventional `var_dump()` technique. We'll also touch on debugging from the command line. Learn to dance in PHP with step debugging.

Transcript

1. legacy.joind.in/24817 @SammyK #phpworld Sammy Kaye Powers Dance The Washington, D.C. - 2018 An Intro To Step Debugging in
2. legacy.joind.in/24817 @SammyK #phpworld CLOSER :) Get
3. Thanks to Our Sponsors 2018
4. legacy.joind.in/24817 @SammyK #phpworld Download the slides legacy.joind.in/24817
5. legacy.joind.in/24817 @SammyK #phpworld Does not work for
6. legacy.joind.in/24817 @SammyK #phpworld What is Debugging? Finding and fixing unexpected behavior in code
7. So you write Some Code
8. Does not work
9. legacy.joind.in/24817 @SammyK #phpworld You could check the Error logs
10. legacy.joind.in/24817 @SammyK #phpworld All the things var_dump()
11. legacy.joind.in/24817 @SammyK #phpworld
12. legacy.joind.in/24817 @SammyK #phpworld OR
13. legacy.joind.in/24817 @SammyK #phpworld Use a ‘er
14. legacy.joind.in/24817 @SammyK #phpworld Kate Gregory “ I'm not saying, ‘don't use printf()’, [...] but I think it's insane to use printf() on day one of learning C++. [...] I would first say use the debugger. Episode 30: Stop Teaching C (When Teaching C++)
15. legacy.joind.in/24817 @SammyK #phpworld …now is the perfect time to learn Step Debugging BNEW! Professional
16. legacy.joind.in/24817 @SammyK #phpworld Some step-debugging Jargon
17. legacy.joind.in/24817 @SammyK #phpworld a signal that tells the debugger to pause the execution of your code Breakpoint
18. legacy.joind.in/24817 @SammyK #phpworld run to the next breakpoint Resume Program
19. legacy.joind.in/24817 @SammyK #phpworld advance to the next line in the same scope Step Over
20. legacy.joind.in/24817 @SammyK #phpworld if the next line is a function call, enter the function Step Into
21. legacy.joind.in/24817 @SammyK #phpworld run to the end of the current function Step Out
22. legacy.joind.in/24817 @SammyK #phpworld shows the execution path to the point where the code was paused Frames I… don’t have a cool drawing for “frames”…
23. legacy.joind.in/24817 @SammyK #phpworld & Environment Setup
24. legacy.joind.in/24817 @SammyK #phpworld
25. legacy.joind.in/24817 @SammyK #phpworld https://xdebug.org/docs/remote Debug client (DBGp protocol)
26. legacy.joind.in/24817 @SammyK #phpworld Setup
27. #1 Start listening to debugging connections
28. #2 Set a Breakpoint
29. legacy.joind.in/24817 @SammyK #phpworld Done!
30. legacy.joind.in/24817 @SammyK #phpworld Setup
31. configured installed installed
32. on Homebrew Install + $ brew install php $ pecl install xdebug
33. on APT Install + $ add-apt-repository -y \ ppa:ondrej/php $ apt-get update $ apt-get install php7.2-xdebug
34. https://xdebug.org/docs/install Install +
36. legacy.joind.in/24817 @SammyK #phpworld Configure
37. $ php --ini
38. $ php --ini
39. $ sudo vi /usr/local/etc/php/ 7.2/conf.d/ext-xdebug.ini
40. $ php -i | grep xdebug
41. legacy.joind.in/24817 @SammyK #phpworld Start a session or CLI
42. legacy.joind.in/24817 @SammyK #phpworld Query Param XDEBUG_SESSION_START
43. legacy.joind.in/24817 @SammyK #phpworld Cookie XDEBUG_SESSION
44. legacy.joind.in/24817 @SammyK #phpworld
45. legacy.joind.in/24817 @SammyK #phpworld
46. legacy.joind.in/24817 @SammyK #phpworld Env Variable export XDEBUG_CONFIG="idekey=foo" CLI
47. legacy.joind.in/24817 @SammyK #phpworld Env Variable set XDEBUG_CONFIG="idekey=foo" CLI
48. legacy.joind.in/24817 @SammyK #phpworld Don’t forget to unset set XDEBUG_CONFIG= unset XDEBUG_CONFIG when you’re done
49. legacy.joind.in/24817 @SammyK #phpworld alias debug-on='export XDEBUG_CONFIG="ide_key=foo"' alias debug-off='unset XDEBUG_CONFIG' Bash alias
50. legacy.joind.in/24817 @SammyK #phpworld Run some code! & CLI
51. legacy.joind.in/24817 @SammyK #phpworld PHP’s Built-in Web Server run locally using
52. legacy.joind.in/24817 @SammyK #phpworld Built right into the CLI SAPI! $ php -S 127.0.0.1:8888
53. legacy.joind.in/24817 @SammyK #phpworld
54. legacy.joind.in/24817 @SammyK #phpworld learn? What did we
55. legacy.joind.in/24817 @SammyK #phpworld +
56. legacy.joind.in/24817 @SammyK #phpworld
57. legacy.joind.in/24817 @SammyK #phpworld
58. legacy.joind.in/24817 @SammyK #phpworld CLI
59. legacy.joind.in/24817 @SammyK #phpworld Debugging In Action
60. legacy.joind.in/24817 @SammyK #phpworld
61. legacy.joind.in/24817 @SammyK #phpworld In production
62. But wait! * (see me after class for more info)
63. Sammy Kaye Powers Thanks! /24817 @SammyK SammyK.me Host of @PHPRoundtable legacy.