When developing WordPress plugins or themes, it's a good idea to have tools in place to help improve your code quality and debug your code in the case of errors. Enabling error logs, inspecting the values of variables during code execution, and looking at the database queries being run are all tools that developers can use to find and fix problems. In this workshop, we'll dive into some of the options built into WordPress that you have at your disposal, learn about various debugging plugins and their uses, as well as look at one or two third-party tools to consider.

1. Jonathan Bossenger
Let’s Code
Learn.WordPress.org
Debugging in WordPress

2. 2
👋🏽
Welcome!
As you join, please make sure you have your local
development environment ready:
• A local WordPress installation
• A code editor like VSCode or Sublime
• https://github.com/jonathanbossenger/wp-learn-
debugging/releases/download/1.0.0/wp-learn-
debugging.1.0.0.zip
Then, let everyone know in the chat where you’re joining
us from…
Hello!
○ My name is Jonathan Bossenger
○ From Cape Town, South Africa
○ Developer educator at Automattic
○ Sponsored to work with the Training Team
○ jonathanbossenger.com

3. Learn.WordPress.org
Debugging in
WordPress
Jonathan Bossenger

4. Announcements
○ Welcome, and thanks to Meagan for co-hosting.
○ Please let me know if you can’t see this slide!
○ We are presenting in focus mode, but please feel free to enable your video.
○ You are welcome to ask questions.
○ You are welcome to post questions in the chat, or unmute to ask questions.

5. Announcements
○ Make sure your local install is ready
• https://github.com/jonathanbossenger/wp-learn-
debugging/releases/download/1.0.0/wp-learn-debugging.1.0.0.zip
• https://www.howtogeek.com/789559/how-to-stop-safari-from-automatically-
unzipping-downloaded-files-on-mac/
○ If I am going too fast, please let me know!
○ We will be posting this session to https://wordpress.tv/ afterwards
○ For more WordPress focused content please visit https://learn.wordpress.org/

6. Learning Outcomes
1. Enabling the WordPress debug constants
• WP_DEBUG
• WP_DEBUG_DISPLAY
• WP_DEBUG_LOG
• SCRIPT_DEBUG
• SAVEQUERIES
2. Debugging plugins
• Debug Bar
• Query Monitor

7. Learning Outcomes
1. Additional tools
• Ray
• Xdebug

8. Let’s code.

9. Resources
○ https://github.com/jonathanbossenger/wp-learn-debugging/releases/download/1.0.0/wp-learn-
debugging.1.0.0.zip
○ https://wordpress.org/documentation/article/debugging-in-wordpress/
○ https://wordpress.org/plugins/debug-bar/
○ https://wordpress.org/plugins/query-monitor/
○ https://wordpress.org/plugins/spatie-ray/
○ https://xdebug.org/
○ https://learnxdebug.com/